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  • Genetics
  • 101
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 283-297 
    ISSN: 0192-253X
    Keywords: Dictyostelium discoideum ; cAMP-unresponsive mutants ; parasexual genetic analysis ; cell differentiation ; chemotaxis to folate and cAMP ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: To find mutants of Dictyostelium discoideum that are unable to respond to exogenous cAMP signals (frigid mutants), amoebae of 218 independent aggregation-deficient mutants were treated in suspension with artificial pulses of cAMP and screened for the capacity to form EDTA-resistant cohesion sites. Eleven frigid mutants were identified and further characterized. Using parasexual genetic techniques, these strains were assigned to five complementation groups (fgdA-E) and the fgd loci were mapped in three linkage groups: fgdA and D in group II, fgdC in group III, and fgdB and E in group VII. Biochemical and physiological experiments with these strains indicated that fgd mutants are of two general types. When starved, strains in groups fgdB, D, and E failed to produce detectable levels of membrane-associated cAMP phosphodiesterase, surface cAMP receptors, or extracellular phosphodiesterase inhibitor, and the cells continued to respond chemotactically to folate. Thus, these strains are probably arrested in the vegetative phase or very early in development. In contrast, strains in groups fgdA and C produced low levels of cAMP receptors and secreted phosphodiesterase inhibitor. Moreover, after starvation, some of these mutants elicited a weak chemotactic response to cAMP. Therefore, unlike the former group of mutants, these strains appear to initiate development when starved, but the process is blocked at an early stage.
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  • 102
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 365-365 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
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  • 103
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
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  • 104
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 7-23 
    ISSN: 0192-253X
    Keywords: gene expression ; superoxide dismutase ; Zea mays ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Immunoassays for the cytosolic and mitochondrial superoxide dismutases (SOD) of maize were developed and used to study the expression of these proteins in the maize seedling. The genetically distinct proteins, SOD-3 and SOD-4, are preferentially expressed in the scutellum, comprising approximately 1% of the total water-soluble protein of that tissue. SOD-2, SOD-3, and SOD-4 are synthesized in the scutellum during early sporophytic development, probably on cytosolic ribosomes. Two-dimensional gel electrophoresis of crude scutellar extracts indicates that significant changes occur in the protein composition of the maize scutellum following seed imbibition. Using the immunoassays, a maize line exhibiting a significant reduction in cyanide-sensitive SOD protein was identified.
    Additional Material: 8 Ill.
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  • 105
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 106
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 177-177 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 107
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 179-196 
    ISSN: 0192-253X
    Keywords: alcohol dehydrogenase ; regulatory ; mutant ; mutable alleles ; organ-specific ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Three new mutant alleles of maize alcohol dehydrogenase-1 (Adh 1) were recovered following allyl alcohol selection of pollen. Each is altered in quantitative, organ-specific, regulatory properties. All mutant sites act in cis to the structural gene component. One mutant arose spontaneously, one followed indirectly from irradiation with high Z accelerated particles, and one was induced by an autonomous mutator system. Each mutant is assessed in three organs by utilizing ADH allozyme ratios that were quantified at the level of ADH enzyme activity and either [3H]-Leu incorporation into newly synthesized ADH 1 subunits or direct protein determinations. One mutation simultaneously raises Adh 1 expression in one organ and lowers it in another, another affects expression in one organ only, and another is extremely underexpressed in all organs but is unstable. This unstable allele has generated derivative mutant alleles that have less or zero ADH expression. We do not yet know whether or not coding sequences are involved in these mutants. We conclude that information for organ specificity and quantitative behavior resides near or within Adh 1 coding sequences.
    Additional Material: 6 Ill.
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  • 108
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 109
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 69-89 
    ISSN: 0192-253X
    Keywords: female sterility mutations ; fusome ; incomplete cytokinesis ; interconnected sibling cells ; ongenesis ; ovarian tumor genes ; polytene chromnsomes ; pseudonurse cells ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A comparative cytological study was made of oogenesis in flies carrying various mutant alleles of the female sterile gene otu. It resides at 22.7 on the genetic map and within subdivision 7F of the cytological map of the X-chromosome. Each of the five ethyl methane sulfonate-induced mutations observed falls into one of three classes. In class 1, most mutant ovarioles lack germ cells; in class 2, most mutant ovarioles contain tumorous chambers; and in class 3 mutants, chambers occur that possess defective oocytes. The otu2 allele belongs to class 1; otu1 to class 2; and otu3, otu4, and otu5 to class 3. The mutations have no effects upon female viability or upon the viability and fertility of hemizygous males. Heterozygous females are fertile and have cytologically normal ovaries. In otu5 homozygotes, all ovarioles contain egg chambers, but oogenesis is prematurely terminated to produce a pseudo-stage 12 oocyte. Ovarioles from otu3 and from otu4 homozygotes contain both ovarian tumors and oocytes. Pseudonurse cells (PNC), which are cystocytes that have stopped dividing and have entered the nurse cell mode of development, are also abundant. PNCs contain polytene chromosomes. Since the homologs are paired, each nucleus has the haploid number of chromosomes. In chambers lacking an oocyte, the number of PNCs is less than the normal number of nurse cells. In chambers containing an oocyte, the number of accompanying nurse cells may be 15, or above or below normal. In vitellogenic chambers, the chromosomes in the nurse cells connected directly to the oocyte are more expanded than those in more distant nurse cells. The KA14 deficiency lacks the plus allele of otu. KA14 heterozygotes are fertile and have cytologically normal ovaries. When females carry KA14 and otu1, otu3, otu4, or otu5, 80% of their ovarioles are agametic. When females carry otu2 and one of the other mutant alleles, the ovarioles proceed further in development. So otu2 produces a product that has a beneficial effect on the test allele. When two different otu alleles are combined in a single fly, the phenotype of the hybrid ovary usually most resembles that of the ovary homozygous for the “stronger” allele (the otu mutant that allows oogenesis to proceed farthest). The results indicate that the product of the otu+ locus functions at least three different times during oogenesis; first to permit oogonia to proliferate, second to control the division and differentiation of germarial cystocytes, and third to facilitate the normal growth of the ooplasm. The gene product appears to be required in higher concentrations at each developmental period. The lesions produced by the mutations are thought to interfere with the stability or functioning of the gene product, and the ovarian phenotype produced by a given genotype depends upon the concentration of functional gene product available to the germ cells.
    Additional Material: 8 Ill.
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  • 110
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 103-113 
    ISSN: 0192-253X
    Keywords: Drosophila melanogaster ; Polycomb ; homoeotic mutation ; determination ; maternal effect ; embryogenesis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: When heterozygous, dominant mutant alleles of the Polycomb locus are associated with a variety of adult homoeotic effects. Zygotes homozygous for these alleles die as late embryos showing homoeotic transformation of head, thoracic, and abdominal segments. This study shows that embryos homozygous for Pc3 are more extreme than those homozygous for Pc1 or Pc2. Moreover, Pc1/Pc3 heterozygotes are more extensively transformed if their mothers were Pc3/ + than if they were Pc1/ +; this effect does not depend on zygotic genetic background and must be maternal in nature. Embryos homozygous for Pc3 are less extreme if they arise from Pc3/ + / + than from Pc3/ + mothers. These results strongly suggest that the Polycomb locus acts maternally as well as zygotically to affect early determinative decisions.
    Additional Material: 5 Ill.
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  • 111
    ISSN: 0192-253X
    Keywords: B cell development ; immunoglobulin M ; B cell tumor ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Tumors of B lymphocyte origin have been used as models for normal B cells “frozen” at particular stages of their development. Surface properties, amount, and intracellular location of immunoglobulin and the synthesis of J chain have all been used as indicators of developmental stages. Each requires special techniques or yields data that are difficult to compare from one experiment to the next. For these reasons, we have developed a metric for B cell development that is simple to perform and allows quick quantitative comparisons of cell lines.It has recently been established that the membrane (μm) and secreted (μs) forms of the IgM heavy chain differ at their extreme carboxy termini. The two proteins differ slightly in size and are easily distinguished when they are compared without their carbohydrate on sodium dodecyl sulfate (SDS) polyacrylamide gels. We have examined four mouse tumors derived from the B lymphocyte lineage whose phenotypes resemble late pre-B cells (internal μ only; uninduced 70Z/3), small B lymphocytes (high levels of surface IgM; LPS-induced 70Z/3, WEHI 231), lymphoblasts (both membrane and secreted IgM; WEHI 279.1), and plasma cells (copious IgM secretion; MOPC 104E). Despite the fact the 70Z/3 and WEHI 231 secrete no detectable IgM, all of the tumors synthesize at least intracellular forms of both μm and μs. The proportion of μm is stable and is characteristic of each tumor. The 70Z/3 cells and WEHI 231 cells synthesize about 75% of their total μ as μm; WEHI 279.1 cells synthesize about 30% and MOPC 104E cells about 5% of their total μ as μm. The population of LPS-stimulated B lymphocytes shows a similar progression during its differentiation. The proportion of μm correlates with other developmentally regulated parameters (Fc receptor, Ia and plasma cell antigen levels, and J chain) and can be used as a simple metric for comparison with developing B lymphocytes and determination of the developmental stage of a B cell tumor.
    Additional Material: 4 Ill.
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  • 112
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 143-154 
    ISSN: 0192-253X
    Keywords: imaginal neurogenesis ; visual development ; genetic mosaics ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The neural phenotype of an imaginal disc degenerate mutant l(1)d deg-3 was studied in histological sections. The mutant larvae showed severe abnormalities in the imaginal neural development. Gynandromorphs, which are composed of genetically mutant and nonmutant cells, were generated and analyzed as late larvae. The results of mosaic analysis were consistent with l(1)d deg-3 gene acting autonomously in the imaginal disc and imaginal neural cells. The optic lobe development patterns observed in the larval mosaics provided evidence for an eye disc-optic lobe interaction during the late third instar larval stage.
    Additional Material: 6 Ill.
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  • 113
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 329-345 
    ISSN: 0192-253X
    Keywords: Drosophila embryo ; mutation ; myogenesis ; fibrillogenesis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The I(1)fdg mutation demonstrates two separate phases of lethality, depending on developmental conditions. At 32-33°C, an embryonic lethality is expressed whereas at lower temperatures a larval-pupal lethality is observed. This larval-pupal lethality characteristically produces noncondensed, curved puparia, and since the contraction of the pupa depends on strong muscular contraction, this phase of lethality implicates some involvement of abnormal musculature. The embryonic expression of I(1)fdg at 32-33°C is the subject of this study. In these embryos, which are alive but immobile (incapable of hatching), the fibrillar organization and fiber morphology of the somatic musculature varies from being apparently normal to being grossly abnormal. While the abnormalities appear as unusual distributions of fiber organelles, abnormal convolutions of the muscle fibers, and disorganizations of fibrillar components, it seems most probable that the underlying defect ultimately responsible resides in some system essential for Z body alignment and sarcomere formation. Accompanying the embryonic lethality, certain abnormalities in midgut development are observed which at present do not appear to be related to the defects observed in the somatic muscle.
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  • 114
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 347-363 
    ISSN: 0192-253X
    Keywords: Drosophila melanogaster ; muscle defect ; genetic mosaics ; allelic variability ; intragenic complementation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The recessive X-linked mutation erect wing (ewg), in Drosophila melanogaster, was characterized as a flightless behavioral mutant which specifically lacked the dorsal longitudinal flight muscles [1]. This mutation was mapped distal to the X chromosomal locus yellow, and further to the cytological segment 1 A 1 to 1 B2-3 [2]. Several lethal complementation groups have been mapped to this interval [3]. Our complementation tests show that ewg is allelic to one lethal complementation group in the region 1 A 1 to 1 B2-3. A further analysis of ewg and several lethal alleles isolated at this locus was undertaken in the present investigation. Most of the lethal alleles at this locus lead to a late embryonic or early larval lethal phase, indicating that the ewg+ gene product is necessary for the development of more than just the dorsal longitudinal flight muscles. Intragenic complementation was observed for some of the ewg lethal alleles. Genetic mosaics with ewg lethal alleles showed that mutant cell clones in cuticular structures are viable. Mosaic analysis is consistent with a mesodermal defect associated with the locus.
    Additional Material: 2 Ill.
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  • 115
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    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 41-51 
    ISSN: 0192-253X
    Keywords: Artemia ; histone synthesis ; histone genes ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The synthesis of histones and presence of histone mRNA sequences in embryos and larvae of the brine shrimp, Artemia, were investigated. Radiolabeling of proteins synthesized in vivo followed by electrophoretic and fluorographic analysis confirmed the prediction that histone synthesis is coordinated with the wave of DNA replication in newly hatched larvae. No histone synthesis occurs during development of encysted embryos. Hybridization of cloned Artemia histone gene DNA to total cell RNA indicated that dormant encysted embryos do not contain “masked” messenger RNA.
    Additional Material: 4 Ill.
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  • 116
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 91-102 
    ISSN: 0192-253X
    Keywords: hyperthermia ; heat shock ; phenocopy ; teratogenesis ; morphogenesis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have for some years been making use of phenocopies in Drosophila, as induced by heat shock, as tools for studies of the molecular events in morphogenesis [18, 21, 22]. In this paper, we have brought together some accumulated information on the conditions for phenocopy production, on a temporal sequence of sensitivity to induction, and on the nature of many of the morphogenetic abnormalities that can be induced. In general, the induction of phenocopies by heat shock requires conditions drastic enough to turn off transcriptional activities but not extreme enough to prevent recovery. This situation is most easily achieved in pupal stages where heat resistance is high, but even in this range, resistance varies with the stage of development.The phenocopies described resemble, for the most part, mutants that affect structures derived from epithelial differentiation or muscle development.
    Additional Material: 5 Ill.
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  • 117
    ISSN: 0192-253X
    Keywords: tumorous and nontumorous genotypes ; DNA amplification ; repetitive DNA ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The possible relevance of changes in amounts of highly repetitive DNA sequences for plant differentiation and dedifferentiation processes has been suggested in several cases. Data are lacking however on (1) the genetic control of these phenomena and (2) cause-effect relationships between DNA amplification and specific ontogenetic patterns.The present study was carried out on a Nicotiana genetic system consisting of the tumorous amphidiploid N glauca X N langsdorffii, a nontumorous mutant of it, their F1, and a backcross to the tumorous parent. Backcross segregation ratios were shown to be compatible with a “single gene” hypothesis, the F1 plant being nontumorous but showing a low percentage of tumors induced by wounds, 6-azauracil or X-rays.In vitro studies of excised pith tissue grown on Linsmaier and Skoog medium for different periods of time showed the presence, confirmed by cytological analyses, of amplification of highly repetitive sequences only in the nontumorous stock, as judged by reassociation experiments in the first 24-96 hours of culture. CsCl analytical ultracentrifugation of those sequences showed the appearance in the same stock of a heavy DNA satellite (density = 1.721 gm/ml), whose presence was also confirmed by derivative melting curves.Amplification seemed to be essential for the initiation of cell division, which was completely inhibited in the nontumorous genotype and partially influenced in the F1 by incorporation during the critical period (24-96 hours of the primary explant) of 5-bromo-2′-deoxy-uridine.The results are discussed in terms of an hypothesis of an integrated gene-controlled, hormone-mediated regulatory system of cell proliferation involving changes in target repetitive DNA sequences.
    Additional Material: 8 Ill.
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  • 118
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 115-128 
    ISSN: 0192-253X
    Keywords: Drosophila melanogaster ; polygenic variation ; pattern formation ; wing veins ; campaniform sensillae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: This study was designed to measure the degree of correlation between vein formation and the specification of campaniform sensillae positions in the wing of Drosophila melanogaster. The campaniform sensillae are sensory organs placed at various locations on the wing. Those on the third longitudinal vein (L3) were the focus of this analysis. The system of polygenic modifiers of vein length is comparatively simple, as shown in whole chromosome assays of selected lines. This variability provides a sensitive method of altering vein-forming ability and of assessing correlated changes in other parts of the vein pattern. In selection lines of veinlet, sensillae were displaced toward the base of the wing as vein length decreased by distal loss of vein material. Changes in the amount of vein were, however, not directly proportional to changes in sensillae positions. The more distal sensillae were shifted the largest amount. In the mutant tilt, in which reduced L3 vein-forming competence results in subterminal gaps, distal campaniform sensillae were almost completely eliminated. The remaining sensillae were shifted toward the base of the wing where vein formation is normal. The placement of sensillae therefore appears to be sensitive to the same underlying determinants involved in vein-forming competence.
    Additional Material: 6 Ill.
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  • 119
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 155-163 
    ISSN: 0192-253X
    Keywords: shiverer mouse ; myelin ; myelin basic protein ; myelination ; proteolipid protein ; sciatic nerve ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The central nervous system of the shiverer mouse is known to be severely deficient in myelin. Animals heterozygous for this autosomal-recessive mutation were crossed, and the myelin proteins were examined in the brains and spinal cords of shiverers and unaffected littermates among the offspring. In the brains and spinal cords of nine of the 14 unaffected littermates examined, the quantities of the myelin basic and proteolipid proteins were lower than normal. Furthermore, in the brains of heterozygotes 33 to ∼ 150 days old, the myelin basic and proteolipid proteins were reduced in amount, compared to wild-type controls; the myelin basic protein was also present in subnormal amounts in the spinal cords from heterozygous animals at the ages of 17 to 150 days. More severe reductions in the quantities of the myelin proteins were observed in central nervous system tissue from homozygous shiverer mice, and the quantity of the myelin proteolipid protein in the central nervous system of the shiverer mouse, expressed as a ratio to the control value at each age, underwent a developmental decline. In heterozygotes, as well as shiverers, the peripheral nerves were also deficient in the P1 and Pr proteins, which are the same as the basic proteins in rodent central nervous system myelin. The findings regarding heterozygotes suggest that the defective primary gene product in the shiverer mouse could be the myelin basic protein itself or a protein required for a rate-limiting step in the processing of the myelin basic protein.
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  • 120
    ISSN: 0192-253X
    Keywords: urate oxidase ; 20-hydroxyecdysone ; Drosophila melanogaster ; Malpighian tubules ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The tissue-specific enzyme urate oxidase is confined exclusively to the Malpighian tubules of Drosophila melanogaster and expressed only in the third-instar larva and the adult. Shortly before pupariation urate oxidase activity declines precipitously and is not detectable 24 hours later. That 20-hydroxyecdysone is the factor that triggers the disappearance of urate oxidase activity in late third-instar larvae is demonstrated using the temperature sensitive mutant ecd1 which at the nonpermissive temperature of 29°C fails to accumulate a sufficient concentration of 20-hydroxyecdysone necessary for puparium formation and thus remains a third-instar larva for 1 to 2 weeks before death. Both the life cycle and the temporal profile of urate oxidase activity in ecd1 larvae at 19°C is identical to that of the wild type. However, at 29°C ecd1 third-instar larvae retain high urate oxidase activity. A precipitous decline in urate oxidase activity is observed when ecd1 larvae at 29°C are fed 20-hydroxyecdysone. These data implicate 20-hydroxyecdysone in the process that controls the rapid decline of urate oxidase activity at the time of puparium formation. In whole homogenates of Malpighian tubules, the urate oxidase polypeptide was identified in SDS-polyacrylamide gels by its Rf with respect to homogeneously pure Drosophila urate oxidase and also by immunoprecipitation with rabbit anti-Drosophila urate oxidase IgG. Throughout development the amount of the urate oxidase polypeptide is correlated with the magnitude of urate oxidase activity.
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  • 121
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 247-253 
    ISSN: 0192-253X
    Keywords: H-Y antigen ; sex determination ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Karyotypically XY individuals of the C57BL/6J-YPOS mouse stock develop as females or hermaphrodites, but never as normal males. The aberrant sexual development results from the interaction of the C57BL/6J genetic background with the M. poschiavinus-derived Y chromosome. XY females from this stock were assayed for H-Y antigen. By the criteria of skin-grafting, the cell-mediated lympholysis test, and the popliteal lymph node assay, these XY females are antigenically indistinguishable from normal C57BL/6 males. Implications for the hypothesis that H-Y antigen induces formation of the mammalian testis are discussed.
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  • 122
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 275-282 
    ISSN: 0192-253X
    Keywords: Drosophila ; sex chromosomes ; gene dosage ; gene expression ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In Drosophila, the ratio of the number of X chromosomes to sets of other chromosomes initiates a series of events which result in sexual differentiation. In addition, this ratio establishes dosage compensation, a mechanism which equalizes the products of X-linked genes in males and females. The present review discusses possible genetic entities responsible for the interpretation of chromosomal sex and subsequent sex-mediated regulation during development.
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  • 123
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    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 3 (1982), S. 309-327 
    ISSN: 0192-253X
    Keywords: Drosophila melanogaster ; DNA polymerase ; developmental enzyme profile ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: An assay procedure was developed that allowed the first reproducible measurement of DNA polymerase activity in all developmental stages of Drosophila melanogaster. Evidence is presented that the same enzymatic species is present in extracts of embryos, pupae, and adults of both sexes and that this activity has many properties similar to vertebrate α-polymerases. Polymerase activity per individual is low in embryos and rises steadily through larval instars, reaches a peak in early pupae, declines through the late pupal period, and remains low in newly eclosed adults of both sexes. A dramatic increase is observed in adult females as mature oocytes are formed. This pattern of enzyme activity is completely coincident with changes in DNA levels during development, and suggests that the Drosophila enzyme, like vertebrate α-polymerases, functions in cellular DNA replication. Two mutagen-sensitive mutants, deficient in both replication on undamaged templates and postreplication repair, were found to have normal levels of this α-polymerase activity. Our results suggest that a single enzymatic species of α-polymerase holoenzyme exists in Drosophila and is common to all developmental stages of this organism.
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  • 124
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    Springer
    Journal of molecular evolution 17 (1981), S. 167-181 
    ISSN: 1432-1432
    Keywords: Evolution ; Genetics ; REH theory ; Mutations ; Natural selection ; Nucleic acids ; Proteins ; Paleogenetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have independently repeated the computer simulations on which Nei and Tateno (1978) base their criticism of REH theory and have extended the analysis to include mRNAs as well as proteins. The simulation data confirm the correctness of the REH method. The high average value of the fixation intensity μ2 found by Nei and Tateno is due to two factors: 1) they reported only the five replications in which μ2 was high, excluding the forty-five replications containing the more representative data;and 2) the lack of information, inherent to protein sequence data, about fixed mutations at the third nucleotide position within codons, as the values are lower when the estimate is made from the mRNAs that code for the proteins. REH values calculated from protein or nucleic acid data on the basis of the equiprobability of genetic events underestimate, not overestimate, the total fixed mutations. In REH theory the experimental data determine the estimate T2 of the time average number of codons that have been free to fix mutations during a given period of divergence. In the method of Nei and Tateno it is assumed, despite evidence to the contrary, that every amino acid position may fix a mutation. Under the latter assumption, the measure X2 of genetic divergence suggested by Nei and Tateno is not tenable: values of X2 for theα hemoglobin divergences are less than the minimum number of fixed substitutions known to have occurred. Within the context of REH theory, a paradox, first posed by Zuckerkandl, with respect to the high rate of covarion turnover and the nature of general function sites in proteins is resolved.
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  • 125
    ISSN: 1432-069X
    Keywords: Genetics ; Hair dysplasia ; Scanning electron microscopy ; Uncombable hair syndrome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 126
    ISSN: 1432-0983
    Keywords: Protoplast ; Fusion ; Mitochondrial ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Using a protoplast fusion technique we have been able to locate to the mitochondrial genome of the asporogenous yeast Torulopsis glabrata mutations conferring resistance to oligomycin, antimycin and diuron. When two strains differing in the size of their mtDNAs were fused the mitochondrial markers from the parent with the larger mtDNA (71–91) were transmitted predominantly among the fusion products. Both genetical and physical evidence support the occurrence of recombination in T. glabrata mitochondrial genome. Segregation of the mitochondrial genome appears to take place before the separation of the first bud from the fusion product.
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  • 127
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    Current genetics 4 (1981), S. 177-180 
    ISSN: 1432-0983
    Keywords: Genetics ; Yeasts, protoplasts ; Saccharomyces ; Hansenula
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Protoplasts of petites of strains 625-CI of Saccharomyces diastaticus and NCYC 1085 of Saccharomyces cerevisiae, originally obtained from the National Collection of Yeast Cultures, England, were fused with protoplasts of Candida pseudotropicalis, Saccharomyces rosei, Yaccharbmycesmontanus, Pichiamembranefaciens, Hansenula anomala, Hansenula capsulata, and Schizosac-charomyces pombe. The respiratory-competent products of the fusions were selected on the basis of using at least one of the carbon sources utilized by the petite parent and not by the other. The products of the fusion of C. pseudotropicalis x 1085(p−) consisted of two cell types; an oval cell which utilized both lactose and maltose and fermented lactose vigorously, and a cylindrical form which fermented maltose slowly. The S. rosei x 1085(p−) hybrids had acquired the ability to metabolize and ferment galactose, and to ferment maltose, from the petite parent. The P. membranaefaciens x 625(p−) hybrids acquired the ability to metabolize galactose, sucrose and maltose, but fermented only glucose, weakly, like the P. membranaefaciens parent strain. The H. capsulate x 625(p−) hybrids, unlike the hybrids with P. membranaefaciens or S. rosei, resembled the petite parent morphologically and also had the fermentative abilities of this strain (galactose, maltose, sucrose and starch), and the ability to ferment starch was considerably enhanced. The S. montanus x 625(p−) hybrids acquired the ability to utilize starch. Schizosaccharomyces pombe x 625(p−) hybrids resembled S. pombe morphologically, but had the ability to metabolize galactose and starch. Some of the asci produced by these hybrids contained abnormal numbers of spores. H. anomala x 624 x(p−) hybrids fermented starch, though weakly.
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  • 128
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    Theoretical and applied genetics 60 (1981), S. 229-236 
    ISSN: 1432-2242
    Keywords: Glutenin ; Triticum ; Genetics ; SDS ; Polyacrylamide-gel-electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The high-molecular-weight (HMW) subunits of glutenin from about 185 varieties were fractionated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). About 20 different, major subunits were distinguished by this technique although each variety contained, with only a few exceptions, between 3 and 5 subunits. Further inter-varietal substitution lines to those already described (Payne et al. 1980) were analysed and the results indicate that all the HMW subunits are controlled by the homoeologous group 1 chromosomes. All hexaploid varieties studied except ‘NapHal’ contained two major subunits controlled by chromosome 1D. Their genes were shown to be tightly linked genetically for only four different types of banding patterns were observed. The nominal molecular weights determined after fractionation in 10% polyacrylamide gels were between 110,000 and 115,000 for the larger of the two subunits and between 82,000 and 84,000 for the smaller. One quarter of the varieties contained only one major HMW subunit controlled by chromosome 1B whereas the rest had two. The chromosome 1B subunits were the most varied and nine different banding patterns were detected. All the subunits had mobilities which were intermediate between those of the two chromosome 1D-controlled subunits. Only two types of HMW subunit controlled by chromosome 1A were detected in all the varieties examined; a single variety never contained both of these subunits and 40% of varieties contained neither. The chromosome 1A-controlled subunits had slightly slower mobilities in 10% gels than the largest HMW subunit controlled by chromosome 1D. About 100 single grains were analysed from each of five different crosses of the type (F1 of variety A × variety B) × variety C. The results indicate that the genes on chromosome 1B which control the synthesis of subunits 6, 7, 13, 14 and 17 are allelic, as are the genes of the chromosome 1A-controlled subunits, 1 and 2.
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  • 129
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    Theoretical and applied genetics 60 (1981), S. 265-268 
    ISSN: 1432-2242
    Keywords: Agrocybe ; Genetics ; Fruiting ; Biomass
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In the edible white rot fungus Agrocybe aegerita the threshold from mycelial growth to fruit body formation is under control of a single gene in both monokaryons and dikaryons. The allele su opens the pathway for fruiting and allows the subsequent expression of the fruiter genes fi+ (fruit body initials) and fb + (fruit bodies). Its allele, su +, suppresses monokaryotic fruiting completely and restricts dikaryotic fruiting drastically. The detection of this threshold gene su +/su and its action and interactions has practical implication in that an opportunity for concerted breeding is created. First results indicate that the fruiter genes are involved in two essential parameters of productivity. Both time of fruiting and biomass production depend on the two fruiter genes fi + and fb +. Comparable results obtained with two other basidiomycetes suggest that the genetic control of fruiting in Agrocybe aegerita is a general mechanism which may be made use of in breeding work with other basidiomycetes of economic value.
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  • 130
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    Environmental biology of fishes 6 (1981), S. 357-360 
    ISSN: 1573-5133
    Keywords: Behaviour ; Esterase ; Evolution ; Genetics ; Isozymes ; Stock structure ; Schools ; Starch gel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Synopsis Heterogeneous gene frequencies of Est-1 across groups ofNotropis cornutus provide evidence of behaviourally imposed restrictions on stock structuring. Positive fixation indices (F1S = 0.056 and F1T = 0.085) were reflected by a deficiency of heterozygotes for pooled groups. The degree of subdivision ofN. cornutus stocks cannot be evaluated with the present evidence. but it is likely that their schooling behaviour is associated with significant genotypic structuring of the species.
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  • 131
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    Developmental Genetics 2 (1981) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 132
    ISSN: 0192-253X
    Keywords: nuclear differentiation ; cytoplasmic inheritance ; Paramecium tetraurelia ; mating type ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In P. tetraurelia each cell is determined to express only one of the two complementary mating types, O and E. This determination is under cytoplasmic control and seems to be achieved only by the commitment or noncommitment to the expression of mating type E. All the previously known mutations affecting the differentiation of mating type prevent the expression of the E mating type (O-restricted mutations) without affecting the determination process. An E-restricted mutation was obtained: mtFE. Its phenotypic properties indicate that the mutation affects the determination process itself. When an O cell becomes mtFE/mtFE it acquires the E mating type and an E-determining cytoplasm. We propose that this constitutive determination for the E mating type is due to the inefficiency of a factor which is normally active in an O cell. This factor would act like a repressor and stabilize the E functions under an inactive state.
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  • 133
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    Developmental Genetics 2 (1981), S. 279-290 
    ISSN: 0192-253X
    Keywords: temperature-sensitive mutant ; cytokinin ; hormonal metabolism ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Developmental controls of morphological mutants of Phaseolus vulgaris L. conditioned by two independent loci, DL1 and DL2, were examined through grafting experiments and hydroponic studies. Phenotypes of mutant classes were duplicated by unions of scions and stocks derived from different genotypes. Results indicate that DL1 and DL2 regulate a root and shoot factor respectively, contributing to the mutant types. The allelic dosages of DL1 in the root and DL2 in the shoot rather than the genotype of the whole plant per se determine the severity of the mutant expression. Plants heterozygous for both loci with a temperature-sensitive expression of the mutant phenotype were used to determine physiological components involved. The primary abnormal developmental event associated with the appearance of mutant phenotypes, the restricted root growth at high temperature, could be overcome by the addition of cytokinin in hydroponic solution. These observations suggest that DL1 and DL2 may be related to the regulation of hormonal function or metabolism.
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  • 134
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    Developmental Genetics 2 (1981) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 135
    ISSN: 0192-253X
    Keywords: suspensive and adhesive teratoma cells ; teratoma embryoid bodies ; cell differentiation ; endogenous prostanoid biosynthesis ; long-chain fatty acyl CoA derivatives ; mass fragmentography ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Attachment of the cell surface to a substratum may play a critical role in initiating some cellular developmental commitments and in sustaining differentiation of cells that have already been specialized. Embryoid bodies of teratoma OTT6050 were divided, on day 10 of initial culture, into myogenic adhesive cells which were already (at day 6) characterized by endogenous prostaglandin (PG)I2 formation and little-specialized suspensive cells which formed only thromboxane (TX)B2 in the same culture system. Since at day 10 both cell types reached a stationary phase in which the nature of each cell was mature enough for the analyses with mass fragmentographic technique and gas chromatography- mass spectrometry (GCMS), the total levels of predominant long-chain fatty acyl CoA (acyl CoA) derivatives could be measured comparatively as methyl esters after methanolysis. It was found as a result of major differentiation that adhesive cells had a rather low ratio of arachidonyl CoA to stearyl CoA, although adhesive cells accumulated a larger total amount of acyl CoA derivatives than that accumulated in suspensive cells.
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  • 136
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    Developmental Genetics 2 (1981), S. 99-111 
    ISSN: 0192-253X
    Keywords: CIPC as a mitotic inhibitor of Dictyostelium ; inhibition of Dictyostelium development by CIPC ; CIPC-resistant mutants ; Dictyostelium ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The anti-mitotic herbicide isopropyl N-(3-chlorophenyl) carbamate (CIPC) prevents the growth of amoebae of Dictyostelium discoideum without killing the cells for a period of time equivalent to one generation. During in-hibition, amoebae accumulate in prophase and metaphase of mitosis. After removal of CIPC, they continue through mitosis and then divide.The addition of CIPC to amoebae under starvation conditions prevents aggregation and concomitant cell elongation. The cells, however, do not lose their ability to adhere to a surface, and they remain viable. When CIPC is added to amoebae which have formed streams, it leads to the disintegration of streams into small clusters of cells and to a loss of cell elongation.Post-aggregation stages of development can be inhibited by CIPC at the mound, slug, or Mexican hat stages. Slugs break apart into distinct aggregates.Mutants resistant to CIPC can be obtained easily. Among these mutants, many become temperature sensititive for growth (27°C) or development (27°C or 15.5°C). Others show various abnormalities at the normal temperature (22°C). Most mutants are cross resistant to the microtubule inhibitors nocodazole and thiabendazole, and some are also resistant to CIPC during development.
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  • 137
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    Developmental Genetics 2 (1981), S. 147-158 
    ISSN: 0192-253X
    Keywords: triplo-lethal locus ; Tpl ; gene-dosage ; X chromosome ; Drosophila melanogaster ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Only a single locus (Tpl) is known in the Drosophila melanogaster genome that leads to early lethality when present as a heterozygous duplication (three doses) or deficiency (one dose). We report the recovery of third instar larvae (and of occasional adults) carrying a duplication for the triplo-lethal locus, Dp(Tpl). Karyotype analysis of the larvae showed that the individuals surviving were almost entirely 3X;2A metafemales. We examined the question of whether the entire X or a single X locus was a major factor permitting survival. X-Y translocations were used to produce females hyperploid for different portions of the X and carrying Dp(Tpl). Analysis of metaphase chromosomes by quinacrine fluorescence pattern indicates that the X chromosome region between 6D and 7DE must be present in an extra copy to enhance the survival of Tpl duplication-bearing females. Another type of experiment suggests that it is the region between 7C and 7DE which is essential.
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  • 138
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    Developmental Genetics 2 (1981), S. 131-146 
    ISSN: 0192-253X
    Keywords: rat chimeras ; hooded pigmentation ; melanocyte ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: New, improved media and procedures for making rat chimeric embryos and culturing them in vitro have been developed. We have produced 27 rat chimeras: 20 males and 7 females. This ratio of males to females is consistent with that seen in mouse chimeras, suggesting that rat sex chimeras develop as phenotypic males. By aggregating embryos containing appropriate genetic markers for pigment cell differentiation, it is possible to produce chimeras that elucidate the site of action of the hooded gene. The coat color patterns of black ↔ black hooded chimeras display a white belly spot. In black ↔ albino hooded chimeras, small patches of white hair appear on the head and a large white spot occurs on the belly. Black ↔ agouti hooded chimeras display both agouti and nonagouti pigmentation over the entire surface of the chimera. These animals are fully pigmented with no white spots. In black ↔ albino non-hooded chimeras, rather small irregular patches of black and white hairs are distributed throughout the pelage. Histological examination of sections of hair follicles obtained from the white areas in the head of black ↔ albino hooded chimeras revealed amelanotic melanocytes. On the other hand, hair bulbs from the white belly spots do not contain any such melanocytes. Thus the white hairs of the head are due to the presence of albino melanocytes, but the white hairs of the belly are due to the total absence of melanocytes. All these observations are consistent with the conclusion that the hooded gene acts within melanoblasts, probably to retard their migration from the neural crest and/or to prevent their entrance into the hair follicles of the white areas of hooded rats.
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    Developmental Genetics 2 (1981), S. 171-183 
    ISSN: 0192-253X
    Keywords: sperm ; F9 antigen ; T/t-complex ; immunolabeling ; scanning electron microscopy ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The antigens defined by conventional syngeneic antiserum against F9 embryonal carcinoma cells were localized on mature sperm using immunolabeling and scanning electron microscopy. Labeling patterns were compared for normal (+ / +) mice and mice bearing recessive t-haplotypes. The results showed that antigens detected by intact anti-F9 antiserum are expressed similarly in all genotypes, except for sperm from mice bearing the t12-haplotype where the frequency of labeled cells was reduced. Labeling with the IgM fraction of anti-F9 antiserum was lower on sperm from all t-genotypes examined, with sperm from + /t12 males showing the most marked reduction. In all cases, the labeling patterns were similar, and included a labeling of the whole sperm head with complete anti-F9 antiserum and a restriction of the label to the postacrosomal region when the IgM fraction was used.
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  • 140
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    Developmental Genetics 2 (1981), S. 219-222 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 141
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    Developmental Genetics 2 (1981), S. 49-73 
    ISSN: 0192-253X
    Keywords: determination ; Drosophila ; haltere disc ; homeotic mutation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Mutations at the bithorax locus transform anterior haltere tissue into anterior wing. These transformations could in principle be due to the mutations altering either the expression or cell heredity functions of determination. I have studied two alleles of the bithorax locus bx3 and bx34e using disc culture techniques and found that both produce their transformations by altering the expression of the determined state. I have also found that the expression of the temperature-sensitive allele, bx34e, can be altered by temperature shifts during the culture period. Evidence has been obtained that suggests that such changes in expression do not require growth or cell division.
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  • 142
    ISSN: 0192-253X
    Keywords: temporal genes ; GPDH isozymes ; regulation ; development, Drosophila ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The complete developmental program of glycerol-3-phosphate dehydrogenase in wild type Drosophila is described with respect to activity, isozyme expression, and GPDH-specific CRM. Variants of this developmental program have been isolated from natural populations which affect the rate of accumulation of only the GPDH-3 isozyme in both the larval and adult stages of development. This activity variation segregates as a single gene which is tightly linked to the structural element on Chromosome II, exhibits cis-control, and is tissue specific in expression. This gene meets all the criteria for temporal regulatory genes.
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  • 143
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    Developmental Genetics 2 (1981) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
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  • 144
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    Developmental Genetics 2 (1981), S. 159-170 
    ISSN: 0192-253X
    Keywords: Tetrahymena hegewischi ; timing of maturity ; cellular differentiation ; genetic ; environmental variation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The development of sexual maturity has been studied in Tetrahymena hegewischi. Progeny lines do not typically change from immaturity to mating with all different mating types during a single test interval, but about 30% do mature abruptly. Some testers are more likely than others to participate in the earliest mating reactions of progeny lines which do not mature abruptly. Subcaryonidal vegetative pedigrees of 10 pairs from 4 crosses revealed considerable intrapair variation in the time, measured in fissions, of maturity. The average intrapair coefficient of variation was 20%. A nested ANOVA revealed significant genomic effects on the immaturity interval, but no significant cytoplasmic or caryonidal effects; 56% of the total variation was non-genomic. Growth in different environments had highly significant effects on the immaturity interval. Subclones grown at 27°C with alternate day transfers took on the average 2 to 3 times as many fissions to mature as sister subclones grown at 27°C with daily transfers. Subclones grown at 18°C or 34°C and transferred on alternate days had intermediate maturation times. The greatest range in the immaturity interval among lines of the same genotype was from 34 to 143 fissions. The development of maturity in this species involves genetic control of timing, but the genetic differences are obscured by a large amount of intraclonal variation and sensitivity to the environment.
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  • 145
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    Developmental Genetics 2 (1981) 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
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  • 146
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    Developmental Genetics 2 (1981), S. 369-383 
    ISSN: 0192-253X
    Keywords: Dictyostelium discoideum ; aggregation-deficient mutants ; intracellular cAMP ; adenylate cyclase ; defective spore differentiation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Forty aggregation-deficient mutants of Dictyostelium discoideum were screened for changes in intracellular cAMP during the first 10 hr of starvation. The pools in 39 of the mutants remained low and relatively static during this period. However, amoebae of one mutant, strain HC151, exhibited significantly elevated levels of intracellular cAMP during vegetative growth and for several hours after starvation. A more detailed analysis of this mutant indicated that the elevated cAMP pools in these cells are a consequence of the premature appearance and partial activation of an adenylate cyclase. The mutation(s) altering adenylate cyclase regulation in this strain appears to map in linkage group IV. Complementation tests between strain HC151 and another mutant, HH201, which has recently been shown to produce an adenylate cyclase activity precociously [1], indicated that the mutations affecting adenylate cyclase activity in these strains map at different loci. Although both of these mutations behave recessively in heterozygous diploids with respect to gross development, an examination of early cAMP metabolism and terminal spore differentiation in these diploids suggest that these mutations are at least partially expressed during some stage(s) of the developmental cycle.
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    Developmental Genetics 2 (1981), S. 35-48 
    ISSN: 0192-253X
    Keywords: proteoglycan ; micromelia ; avian embryo ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Embryos homozygous for the recessive lethal gene, micromelia-Abbott, develop a severe form of micromelia, a parrot-like beak, and hemorrhagic skin. Feather development is also retarded. The reduction in length of the long bones of the leg can be traced to their cartilaginous stage Quantitative analysis of sulfated proteoglycan (PGS), a major macromolecular component of cartilage matrix, reveals that mutant tibiae, femora, and sterna contain significantly less uronic acid per μg of DNA than normal rudiments, indicating reduced accumulation of PGS in the mutant. Incorporation of radioactive precursors into cartilage PGS is severely reduced in relatively early developmental stages of a particular organ, but this reduction becomes less severe in cartilage taken from the same rudiment at a later developmental stage. Analysis of the sedimentation rate of PGS in sucrose gradients reveals no difference between normal and mutant in all cartilaginous types at all ages. These results suggest that the quantity and not the quality of PGS is affected in this mutant. The observation that the addition of para-nitrophenyl-β-D-xyloside to the culture medium can stimulate glycosaminoglycan synthesis to normal levels is interpreted to mean that the reduced levels of PGS may be the result of a reduced availability of the xylosylated protein backbone for PGS.
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  • 148
    ISSN: 0192-253X
    Keywords: alcohol dehydrogenase C2 ; isozymes ; temporal locus ; genetics ; chromosome 3 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The tissue specificity of a proposed cis-acting temporal locus (Adh-3t), which regulates alcohol dehydrogenase C2 (ADH-C2) activity in mouse reproductive tissue extracts, has been examined in C5 7BL/6J, SM/J, F1 (SM/J × C5 7BL/6J) mice as well as in progeny of an (F1 [SM/J × C5 7BL/6J] × C5 7BL/6J) back-cross. Electrophoretic variants for ADH-C2, previously used to localize the gene (Adh-3) encoding this enzyme on chromosome 3, enabled the relative parental contributions to ADH-C2 phenotype in F1 and backcross mouse tissues to be determined. These analyses demonstrated that (1) stomach, kidney, lung, adrenals, seminal vesicles, epididymis, uterus, and ovary ADH-C2 is encoded by a single locus (Adh-3); Adh-3t is differentially active in various tissues, eg, lung exhibits no apparent activity whereas the temporal locus is fully active in seminal vesicles; (3) Adh-3t is probably differentically active in different cells of some tissues, eg, adrenals. Specific activity profiles of stomach and epididymal ADH-C2 during the neonatal development of C5 7BL/6J, SM/J, and F1 (SM/J × C5 7BL/6J) male mice supported the proposal for a cis-acting temporal locus for this enzyme. Genetic analyses examining segregation of Adh-3 and Adh-3t among backcross progeny suggested that these are distinct but closely linked loci, since one recombinant among 256 progeny was observed. Linkage data of Adh-3 with Va (varitint-waddler) and de (droopy ear) was also obtained, which suggested that Adh-3 is localized on chromosome 3 between Va and de.
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    Developmental Genetics 2 (1981), S. 357-367 
    ISSN: 0192-253X
    Keywords: amphibian hybrids ; exogastrulation ; hybrid lethality ; nucleocytoplasmic interactions ; triploidy ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Hybrids between species frequently arrest early in development. In the frog hybrid Rana catesbeiana female × Rana clamitans male, the embryo shows a characteristic development to an exogastrula which dies. This hybrid can be rescued by pressure suppression of the second polar body, which results in the addition of another haploid set of R catesbeiana chromosomes to the embryo. The triploid hybrid expresses genes from both species and can develop normally through metamorphosis. The results show that an R catesbeiana egg containing a full haploid set of R clamitans chromosomes is capable of development and that the usual developmental arrest caused by the R clamitans genome responds to chromosomal dosage.
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  • 150
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    Developmental Genetics 2 (1981), S. 203-218 
    ISSN: 0192-253X
    Keywords: cytokinesis ; fusome ; intercellular bridges ; oogenesis ; sterility ; tumor mutations ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The ethyl methane sulfonate-induced mutation, fs(1)1621, resides at 11.7 on the genetic map and within segment 4F1-5A1 of the cytological map of the X chromosome. When homozygous, fs(1)1621 renders females semisterile but has no effect on their viability; nor does it affect the viability or fertility of hemizygous males. Heterozygous females are fertile and have cytologically normal ovaries. The ovaries of homozygous females first produce normal oocytes, which, if fertilized, can develop into adult males or females. After this period, ovarian chambers containing only pseudonurse cells are formed, and finally mutant germaria produce only tumors. These contain hundreds to thousands of cells that appear to be derived from germarial cystocytes, because they occasionally form clones of interconnected cells and also can differentiate into endopolyploid pseudonurse cells. Raising the temperature speeds the rate at which tumors form; lowering it increases the probability of pseudonurse cell differentiation. Df(1)C159 includes fs(1)1621. The pattern of ovarian chamber production is more temperature sensitive in hemizygous females than in homozygous ones. The morphology of hemizygous tumors and the number of dividing cells within them also differ from homozygotes. These observations support the hypothesis that fs(1)1621 is producing a product, that less is produced by one gene than by two, and that the product plays a role in the mitosis and cytokinesis of ovarian cystocytes.
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  • 151
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    Developmental Genetics 2 (1981), S. 237-252 
    ISSN: 0192-253X
    Keywords: Drosophila ; embryonic cultures ; protein synthesis ; stage specific ; differentiation ; two-dimensional gel electrophoresis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The patterns of proteins synthesized during embryonic development in Drosophila melanogaster have been examined by two-dimensional gel electrophoresis. Primary cell cultures prepared from donor embryos synchronized to ± 1 hr were labeled with [35S]methionine at 5, 11.5, 14.5, and 26 hr after oviposition. Of approximately 400 to 500 proteins detected, the synthesis of about 50 is developmentally modulated. The greatest number of changes in the synthesis of stage-specific proteins occurs at 11.5 and 14.5 hr after oviposition, periods just prior to and during the times of the greatest overt morphological and biochemical changes. At 11.5 hr, 35 stage-specific proteins are synthesized, including 19 that are not present at the previous stage examined. At 14.5 hr, 34 stage-specific proteins can be detected, including 11 newly synthesized proteins. However, 12 proteins from the previous stage are no longer synthesized. At the completion of embryonic differentiation, at 26 hr, no new proteins are synthesized and the synthesis of many present in earlier stages has decreased or stopped. Comparison of patterns of embryonic proteins to those synthesized by two Drosophila continuous cell lines reveals that the majority of proteins are common to all. However, only about 40% of the embryonic stage-specific proteins are present in either cell line. In addition, there are several proteins unique to each cell line that are not observed in any of the embryonic stages.
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  • 152
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    Developmental Genetics 2 (1981), S. 1-12 
    ISSN: 0192-253X
    Keywords: β-galactosidase ; preimplantation ; mouse ; Bgl ; paternal effect ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Lysosomal acid hydrolase expression during preimplantation mouse embryogenesis has proved useful in estimating when mRNA transcription commences during this period. Previous work from this laboratory has shown that α-galactosidase and β-glucuronidase undergo 50- to 100-fold increases in activity between the two-cell stage and the blastocyst stage [1, 2]. Here we show that β-galactosidase activity levels undergo a similar change. We also demonstrate that mouse strains with the Bgl-sh allele produce cleavage stage embryos with 2-4-fold higher activity levels than strains with the Bgl-sd allele. Bgl has been shown to control β-galactosidase levels in adult mouse tissues [3]. Unfertilized egg β-galactosidase levels are also regulated by Bgl, but loci distant from Bgl modify egg expression. The distant sites are not observed to act during cleavage. Hybrid embryos (Bgl-sd/h) show intermediate activity levels to the parental types. The timing of the deviation of hybrid embryo β-galactosidase activity levels from maternal-type activity levels is used to estimate when transcription of genes governing β-galactosidase expression occurs.
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  • 153
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    Developmental Genetics 2 (1981), S. 23-34 
    ISSN: 0192-253X
    Keywords: Paramecium tetraurelia ; trichocysts, nuclear differentiation ; cytoplasmic inheritance ; determination ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The mtFE mutation isolated in Paramecium tetraurelia affects mating type differentiation, trichocyst excretion, and viability. Its effect on mating type has already been shown to correspond to a restriction to the E mating type interpreted by an inefficiency of nuclear O-determining factors. In this paper we study the other two phenotypic characteristics whose hereditary transmission displays two unusual features. (1) In crosses between a wild-type strain and the mutant strain, the mutant characteristics do not reappear in F2 in the wild-type cytoplasmic lineage but only in F3 after the homozygous clones have undergone an additional nuclear reorganization. (2) Some F2 wild-type clones, in the mutant cytoplasmic lineage, retain some of the phenotypic characteristics of the mutant. We propose that the mtF gene product plays a role in the control of several macronuclearly differentiated functions.
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  • 154
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    Developmental Genetics 2 (1981), S. 75-87 
    ISSN: 0192-253X
    Keywords: Drosophila melanogaster ; homoeosis ; imaginal discs ; aldehyde oxidase ; pattern formation ; compartments ; selector genes ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In a study of the regulation of enzyme patterns in imaginal discs the aldehyde oxidase pattern was determined for some homoeotic mutations of D. melanogaster. Earlier indications that suggested that this pattern follows the determinitive state of compartments within imaginal discs were confirmed by the aldehyde oxidase (AO) pattern of both the wing and haltere discs from en1; bx3, en1; pbx, and en1; bx3 pbx larvae and the antennal discs from Antp73b and ssa larvae.We additionally analyzed whether AO activity depended on the determinative state of an entire compartment or was expressed autonomously in clones. Homozygous engrailed clones were induced by mitotic recombination. From the AO clones found in normally negative areas of the posterior compartment it was concluded that enzyme activity depended upon the determinative state of the cells and was not a function of the compartment as a whole.The results are described with reference to a scheme in which compartmental and subcompartmental selector genes are thought to determine a binary code on which AO patterns depend.
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  • 155
    ISSN: 0192-253X
    Keywords: Drosophila ; dopa decarboxylase ; female fertility ; temperature sensitive lethal mutant ; differential tissue-specific responses to temperature ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The mutation Ddcts1 effects female sterility when homozygous, hemizygous, or heterozygous over a series of Ddc null alleles (Ddcx) indicating that some aspect of Ddc gene function is necessary for female fertility. Ovary transplant experiments demonstrate that the female sterility phenotype is ovary autonomous. Two to 3% of the total DDC activity measurable in newly hatched females is localized in their previtellogenic ovaries. The degree to which females heterozygous for Ddcts1 over different Ddc null alleles are fertile at 22°C reflects a continuous spectrum of allelic complementation similar to that observed for the effects of these genotypes on viability at 30°C. Fertility of all the Ddcts1/Ddcx females tested is significantly depressed at 30 vis-a-vis 22°C providing evidence that it is the DDC enzyme activity itself which is required for female fertility. Ddcts1/Ddcts1 homozygous and Ddcts1/Df hemizygous females are nonconditionally, completely sterile at 18, 20, 22, 25, and 30°C. Although all homo- and hemizygous females do lay some eggs, no evidence of embryogenesis or fertilization has ever been detected. The absolute, nonconditional sterility of Ddcts1 homo- and hemizygous females stands in stark contrast to the conventional temperature dependent effects of these same genotypes on viability and to the temperature sensitive effects of Ddcts1/Ddcx heterozygous females on both fertility and viability. Reasons for these tissue-specific and genotypic differences are discussed.
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  • 156
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    Developmental Genetics 2 (1981), S. 253-267 
    ISSN: 0192-253X
    Keywords: myxomycete ; Physarum polycephalum ; mating type ; sexual compatibility ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The conversion of the uninucleate amoebal form of Physarum polycephalum to the multi-nucleate plasmodial form is under the control of a genetic region which contains matA (or mt), a determinant of mating specificity. The region is the site of most gad mutations, which give amoebae the ability to produce plasmodia in clones without mating (ie, to self). In the present study, nonselfing revertants were isolated from two matA2-derived gad mutants and two matA3-derived gad mutants. Some revertants were found to have regained exactly, or nearly, the same phenotype as the original matA2 or matA3 strain. Others expressed new mating types, having gained the ability to mate with strains of the parental matA type. The results are compatible with a model in which new mating types arise from forward mutations (gad) and back mutations (npf or no plasmodium formation) occurring successively in a single gene, matA.
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  • 157
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    Developmental Genetics 2 (1981), S. 269-277 
    ISSN: 0192-253X
    Keywords: β-glucuronidase ; androgen ; receptor ; development ; mouse ; kidney ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: During postnatal development of mouse kidney the androgen responsiveness of epithelial cells for β-glucuronidase induction, cellular hypertrophy, and other enzyme inductions appears coincidentally with a rise in androgen receptor protein. Initially, a low level of receptor is present but no response is seen. Beginning at about 12 days of age responsiveness begins to increase, reaches a half-maximal level at 18-20 days, and full responsiveness by 28-30 days. The limiting factor appears to be levels of androgen receptor protein.Our experiments shed no light on the question of why each androgen responsive cell type in the organism differentiates the capacity to induce a different array of proteins. However, they do suggest that responsiveness of the β-glucuronidase gene does not appear until a minimum threshold level of receptor is exceeded, and that the response of the gene may not be saturated even at the highest levels of receptor reached.
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  • 158
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    Developmental Genetics 2 (1981), S. 305-315 
    ISSN: 0192-253X
    Keywords: X-chromosome inactivation ; mouse ; PGK-1 ; embryonic cell lineage ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have used a sensitive electrophoretic technique for estimating the activity, or ratio, of two allozymes of the X-chromosome-linked enzyme phosphoglycerate kinase (PGK-1), in order to investigate the randomness of X-chromosome expression in the derivatives of the three primary cell lineages of the early mouse conceptus. The maternally derived Pgk-1 allele is preferentially expressed in the derivatives of the primitive endoderm and trophectoderm lineages at 6 1/2 days post coitum in Pgk-1a/Pgk-1b heterozygous conceptuses, and in the one informative 5 1/2-day heterozygous conceptus analysed. This evidence for preferential expression of the maternally derived X chromosome (Xm), so soon after the time of X-chromosome inactivation, favors the possibility that the preferential expression of Xm is a consequence of primary non-random X-chromosome inactivation, rather than a secondary selection phenomenon. The majority of embryos analysed at 4 1/2 and 5 1/2 days pc produced only a single PGK-1 band, corresponding to the allozyme produced by the Pgk-1 allele on Xm, although 50% of these embryos should have been heterozygous females. Possible explanations are discussed.
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  • 159
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    Developmental Genetics 2 (1981), S. 319-336 
    ISSN: 0192-253X
    Keywords: maize ; mitochondrial DNA ; recombinant DNA ; cms-T ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Recombinant DNA and hybridization techniques have been used to compare the organization of mitochondrial DNA (mtDNA) from normal (N) and Texas male sterile (T) cytoplasms of maize. Bam H1 restriction fragments of normal mtDNA were cloned and used in molecular hybridizations against Southern blots of Bam H1 digested N and T mtDNA. Fifteen of the 35 fragments were conserved in both N and T as indicated by hybridization to comigrating bands in their restriction patterns. Only three fragments produced autoradiographs whose differences could reasonably be attributed to single changes in the cleavage site of the enzyme while approximately half (17/35) of the clones resulted in more complicated differences between N and T. The autoradiographs produced by these 17 clones indicated multiple cleavage site changes and/or sequence rearrangements of the mtDNA. Patterns of six of these 17 clones indicated partial duplication of the sequence and two showed variation in the intensity of hybridization between N and T, which may be related to the molecular heterogeneity phenomenon found in maize mitochondrial genomes. The large proportion of changes observed between N and T mtDNA indicates that rearrangements may have played an important role in the evolution of the maize mitochondrial genome.
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  • 160
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    Developmental Genetics 2 (1981), S. 185-202 
    ISSN: 0192-253X
    Keywords: somatic DNA alteration ; nuclear differentiation ; mating types ; ciliate genetics ; immunoglobulin genes ; Tetrahymena thermophila ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Experimental data on mating type determination in T. thermophila, collected by Nanney, Allen, and their collaborators over a period of 25 years, are reinterpreted in the light of our current understanding of macronuclear genetics. A strong case is developed supporting the idea that mating type determination involves the developmental alteration of somatic DNA that occurs regularly in developing macronuclei in conjugating pairs. A. testable DNA deletion/splicing model is developed that although based on a few simple, plausible assumptions, explains the observations remarkably well. The model is in (at least) superficial analogy to the mechanism that must be involved to explain the somatic differentiation and alteration of DNA sequences that ultimately constitute an expressed vertebrate immunoglobulin gene. Because of the genetic, biochemical, and micromanipulative versatility of Tetrahymena, it may well turn out to be a uniquely suitable microbial eukaryotic experimental system for the study of developmental alterations of somatic DNA.
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  • 161
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    Developmental Genetics 2 (1981), S. 317-317 
    ISSN: 0192-253X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 162
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    Developmental Genetics 2 (1981), S. 291-303 
    ISSN: 0192-253X
    Keywords: mouse ; trisomy ; gene dosage ; enzyme activity pattern ; phosphoglycerate mutase (PGAM) ; glutamate oxaloacetate transaminase (GOT) ; isozyme ; developmental pattern ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Activity patterns of cytosolic and mitochondrial enzymes of carbohydrate and amino acid metabolism have been measured in murine trisomy 19. In spite of marked hypoplasia, no significant alterations of the patterns (per gram of organ weight) were observed, with the exception of glutamate oxaloacetate transaminase (GOT-1), and phosphoglycerate mutase (PGAM). Clear-cut gene dosage effects in liver, brain, heart, skeletal muscle, and erythrocytes of fetal and newborn mice, confirm the assignment of GOT-1 to chromosome 19. Data obtained for PGAM demonstrate that one of the two different subunits leading to organ-specific isozyme patterns of the dimer enzyme protein is coded on chromosome 19 (gene Pgam-1). Dosage effects are fully expressed in liver, brain, and erythrocytes (AA-type isozyme), but not in skeletal muscle (BB-type isozyme). Dosage effects on the hybrid AA-AB-BB-isozyme pattern in the course of development of the heart muscle, were demonstrated by means of quantitative activity measurement after electrophoretic separation. The comparison of enzyme patterns of eusomic and trisomic erythrocytes, produced after injection of fetal stem cells into irradiated adult carriers (transplantation chimaeras), revealed enzyme activity ratios that were similar to those produced by erythrocytes of adult euploid and trisomic mice. This is in agreement with the chromosome assignments and dosage effects mentioned above.
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  • 163
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    Developmental Genetics 2 (1981), S. 349-356 
    ISSN: 0192-253X
    Keywords: agouti locus ; lethal yellow gene ; MSH ; dibutyryl cyclic AMP ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Alleles at the agouti locus determines the type of pigment produced in hair-bulb melanocytes. In order to analyze the mechanism of agouti gene function, an attempt was made to induce the shift in melanin synthesis in vitro. Skin explants from newborn yellow mice with genotype Ay/a were cultured with the method using membrane-filter and roller tube. Production of black pigment in the hair bulbs was observed when the explants were cultured in the presence of α-melanocyte stimulating hormone (α-MSH). Electron-microscopic observation indicates that the induced black pigments are eumelanin that is normally found in hair-bulb melanocytes of genotypically black mice. The eumelanin synthesis was also induced by cAMP, DbcAMP, or theophylline. This α-MSH-induced eumelanin synthesis was suppressed by actinomycin D or cycloheximide, suggesting that the α-MSH-induced eumelanogenesis requires de novo transcription and/or translation.
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  • 164
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    Developmental Genetics 2 (1981), S. 385-405 
    ISSN: 0192-253X
    Keywords: allelic isozyme variants ; mammalian development ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The past decade has seen an explosion of interest in mammalian embryos. Techniques of molecular and genetic analysis coupled with advances in in vitro culture and experimental manipulation of mammalian embryos have provided important insights into mechanisms of embryogenesis. Many of these recent advances have been facilitated by the use of allelic isozyme variants as autonomous cell markers or representative gene products. Investigations aimed at exploring cell lineages and cell commitment, the timing and regulation of gene expression, X chromosome inactivation, and cell interactions have depended on the availability of appropriate isozyme variants. Results from such experiments are summarized here in order to demonstrate the usefulness of this approach and to stimulate its wider application in developmental biology.
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  • 165
    ISSN: 1432-0983
    Keywords: Chlamydomonas ; Chloroplast ; DNA ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The density, molecular weight, and cellular repetition of DNA molecules associated with the β-DNA satellite of the interfertile algae Chlamydomonas eugametos and C. moewusii are reported. The similarities between these values and those for the chloroplast DNA (cpDNA) in the related alga Chlamydomonas reinhardtii indicate that these satellites represent cpDNA. The buoyant densities of C. eugametos and C. moewusii cpDNAs are indistinguishable from one another, as are those of their respective nuclear DNAs. These densities differ slightly from the densities of the homologous components of C. reinhardtii whole cell DNA. All three species differ with respect to additional minor satellite DNAs and low molecular weight DNAs of unknown cellular location. Differences in the Aval and Smal restriction endonuclease fragmentation patterns of C. eugametos and C. moewusii cpDNAs were employed to study the inheritance of cpDNA in an F1 hybrid which had inherited a non-Mendelian streptomycin resistance marker (sr-2) from the C. eugametos mating-type plus (mt +) parent and in two homoplasmic mitotic segregants from a B 1 hybrid (F1 × C. moewusii) which had been initially heteroplasmic for the resistance marker. Although the cpDNA patterns in the F1 hybrid were similar to those of the C. eugametos ml 1 parent, important differences were noted which suggest that recombination between C. eugametos and C. moewusii cpDNA had occurred. Homoplasmic streptomycin resistant and sensitive mitotic segregants recovered from the B1 hybrid product reveal Aval restriction patterns similar to those of the respective resistant and sensitive parents. These data are consistent with the hypothesis that the sr-2 marker is located in cpDNA and that C. eugametos and C. moewusii cpDNA sequences can coexist in the same chloroplast and, at least sometimes, segregate without extensive recombination. The transmission of low molecular weight DNAs characteristic of C. moewusii but of unknown cellular origin shows no direct correlation with the transmission of the sr-2 marker.
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  • 166
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    Journal of molecular evolution 16 (1980), S. 211-267 
    ISSN: 1432-1432
    Keywords: Nucleic acids ; Proteins ; Natural selection ; Genetics ; Nonrandom molecular divergence ; Nonrandom REH theory ; Evolution ; mRNA ; DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary REH theory is extended by deriving the theoretical equations that permit one to analyze the nonrandom molecular divergence of homologous genes and proteins. The nonrandomicities considered are amino acid and base composition, the frequencies with which each of the four nucleotides is replaced by one of the other three, unequal usage of degenerate codons, distribution of fixed base replacements at the three nucleotide positions within codons, and distributions of fixed base replacements among codons. The latter two distributions turn out to dominate the accuracy of genetic distance estimates. The negative binomial density is used to allow for the unequal mutability of different codon sites, and the implications of its two limiting forms, the Poisson and geometric distributions, are considered. It is shown that the fixation intensity — the average number of base replacements per variable codon - is expressible as the simple product of two factors, the first describing the asymmetry of the distribution of base replacements over the gene and the second defining the ratio of the average probability that a codon will fix a mutation to the probability that it will not. Tables are given relating these features to experimentally observable quantities inα hemoglobin,β hemoglobin, myoglobin, cytochromec, and the parvalbumin group of proteins and to the structure of their corre-sponding genes or mRNAs. The principal results are (1) more accurate methods of estimating parameters of evolutionary interest from experimental gene and protein sequence data, and (2) the fact that change in gene and protein structure has been a much less efficient process than previously believed in the sense of requiring many more base replacements to effect a given structural change than earlier estimation procedures had indicated. This inefficiency is directly traceable to Darwinian selection for the nonrandom gene or protein structures necessary for biological function. The application of these methods is illustrated by detailed consideration of the rabbitα -andβ hemoglobin mRNAs and the proteins for which they code. It is found that these two genes are separated by about 425 fixed base replacements, which is a factor of two greater than earlier estimates. The replacements are distributed over approximately 114 codon sites that were free to accept base mutations during the divergence of these two genes.
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  • 167
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    Psychopharmacology 72 (1980), S. 79-83 
    ISSN: 1432-2072
    Keywords: Avoidance ; Alcohol sensitivity ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract “Most affected” (MA) and “least affected” (LA) rats, bred for extremes in motor impairment following an alcohol challenge, differed in their performance on two active avoidance tasks. In two-way shuttle avoidance, the MA line performed significantly better than the LA group, both in terms of response latencies and percent avoidances. The inferior performance of the LA line persisted across the 15 days of testing, and appeared to reflect an difference in asymptotic performance levels. In one-way avoidance, the MA line showed significantly better acquisition than the LA group; however, this difference dissipated across the 3 days of training. When tested following alcohol administration in either the one-or two-way avoidance paradigm, the MA rats showed a greater performance deficit than LA animals. These data were interpreted as indicating the generality of alcoholrelated line differences to a situation motivated by aversive consequences. Moreover, the line difference in avoidance acquisition represents one of the few non-drug-related phenotypic differences that have been found in these lines. In previous generations, disparate base rates of wheel running have been reported, and the data presented here confirm and extend this finding.
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  • 168
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    Theoretical and applied genetics 57 (1980), S. 91-95 
    ISSN: 1432-2242
    Keywords: Cell culture ; Picloram-tolerance ; Genetics ; Uptake studies ; Nicotiana tabacum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A genetic and preliminary biochemical analysis has been performed on four picloram-tolerant mutants of Nicotiana tabacum that were isolated from cell cultures. The four mutations define three distinct linkage groups. Mutant seedlings incorporate radioactively labeled picloram normally and do not modify or degrade the herbicide in a manner that alters its solubility characteristics.
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  • 169
    ISSN: 1432-2242
    Keywords: Genetics ; Loci ; Powdery mildew ; Prolamin ; Recombination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The linkage relationship among the loci Hor1, Hor2, Ml-k and Ml-a on the short arm of chromosome 5 was studied by progeny testing the F2 generation of two crosses. The loci Hor1 and Hor2 code for polypeptides of the storage protein hordein (prolamin) and the loci Ml-k and Ml-a determine the resistance reaction with some powdery mildew fungi cultures. The order of the loci is Ml-k, Hor1, Ml-a, and Hor2, the first named being nearest the centromere. The recombination percentage between Hor1 and Hor2 was determined in the F1 and F2 generations in both crosses, the combined estimate being 7.4±0.9 per cent. The recombination percentage estimated between Ml-k and Hor1 was 4.0±1.3, between Hor1 and Ml-a, 5.3±1.1, and between Ml-a and Hor2, 6.1±1.2. The estimates involving the Ml- loci were all probably a little too high.
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  • 170
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    Theoretical and applied genetics 56 (1980), S. 5-9 
    ISSN: 1432-2242
    Keywords: Genetics ; Poultry ; Family selection ; Individual selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Responses to single trait selection on individual phenotype and sire-family mean phenotype for survivor's egg weight and rate of lay were measured for a single generation in 13 replicates. Each replicate-selection criterion-trait subclass consisted of eight sire families or 72 females measured and was reproduced from the best 25% of the families or individuals. The realized heritability of egg weight was 0.39 and that of rate of lay was 0.31, both of which were significantly greater than zero but not significantly different from the predicted values based on halfsib correlations in the base population. The standardized response to sire-family selection was less than the response to individual selection for both traits and the difference was significant for rate of lay (0.10; 0.31) but not for egg weight (0.22; 0.39). The predicted responses to sire-family selection were less than those for individual selection for both traits, and the observed responses to sire-family selection were not significantly different from the predicted values for either trait. These experimental results do not disagree with the theoretical expectations of the relative efficiencies of individual and sire-family selection.
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  • 171
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    Theoretical and applied genetics 58 (1980), S. 113-120 
    ISSN: 1432-2242
    Keywords: Glutenin ; Triticum ; Genetics ; SDS-polyacrylamide ; Gel-electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The electrophoretic mobilities of the high-molecular-weight (HMW) subunits of glutenin from 7 varieties were compared by polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate (SDS). In total, 12 subunits were clearly resolved and they had nominal molecular weights of between 95,000 and 140,000. The chromosomes which control their synthesis were determined using monosomic lines and inter-varietal substitution lines. All subunits were shown to be controlled by the homoeologous group 1 chromosomes. Each variety contains between 3 and 5 HMW subunits; two are under the control of the 1D chromosome, 1 or 2 are controlled by chromosome 1B and 0 or 1 by chromosome 1A. The segregation of two 1D-controlled subunits of similar electrophoretic mobilities were analysed in the F2 progeny of crosses between ‘Chinese Spring’ and ‘Holdfast’. The results suggest that the genes which code for the two proteins are allelic.
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  • 172
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    European archives of psychiatry and clinical neuroscience 212 (1969), S. 230-242 
    ISSN: 1433-8491
    Keywords: Twin ; Delirium tremens ; Alcoholism ; Organic Psychoses ; Genetics ; Zwillinge, eineiige ; Delirium tremens ; Alkoholismus ; Organische Psychosen ; Hereditäre Disposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird in dieser Fallstudie über zwei 36 jährige, eineiige Zwillingsbrüder berichtet, die beide in schwerem und absolut gesehen gleichem Ausmaß trunksüchtig sind. Der eine Proband hat 2 mal ein schweres Delirium tremens und einmal ein Prädelir durchgemacht, der andere Proband jedoch hat nie deliriöse Erscheinungen aufgewiesen. Die unterschiedliche Bereitschaft, an Delirium tremens zu erkranken, wird im Zusammenwirken folgender Umstände gesehen: der delirante Proband unterscheidet sich vom nicht deliranten durch eine höhere charakterliche Labilität, eine höhere, seit jeher bestehende Alkoholintoleranz, eine Neigung zu mehrtägigen bis mehrwöchigen Trinkexzessen bei dauernder Tendenz zu einseitiger Ernährung. Die maßgebliche Bedeutung einer genetischen Disposition zum alkoholbedingten Delirium tremens läßt sich für diese Zwillinge nicht nachweisen. Dieser Befund deckt sich mit den Ergebnissen meiner fräheren Untersuchung.
    Notes: Summary This paper reports an investigation of monozygotic twin brothers, aged 36, both suffering from severe alcoholism. One twin (A) had had a severe delirium tremens twice and a pre-delirium once. In contrast, the other twin (B) never showed any signs of delirium tremens. This difference in susceptibility to delirium tremens must be seen in the context that A differed from B in having a more labile personality, an increasing intolerance of alcohol and a tendency to long periods of drinking without taking proper nourishment. Conclusive evidence of a genetic predisposition for delirium tremens could not be proved in these twins. These findings confirm the results of an earlier study.
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  • 173
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    Diabetologia 4 (1968), S. 317-321 
    ISSN: 1432-0428
    Keywords: Genetics ; glucose tolerance ; family ; heterogeneity ; diabetes ; juvenile ; maturity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé La suggestion a été faite que le diabète commençant dans la première moitié de la vie est transmis d'une façon différente du diabète diagnostiqué plus tard.- Nous avons examiné cette hypothèse dans une étude qui compare les membres du premier degré des familles de 735 malades souffrant du diabète avec ceux des 514 sujets de contrôle. Les histoires familiales des malades, rapportées oralement, ont indiqué une prevalence excessive de diabète connu parmi les frères et les soeurs des diabétiques juvéniles. Toutefois, lorsque les membres —supposés normaux — furent examinés, une haute fréquence d'intolérance au glucose non-soupçonnée fut trouvée. Quand la prévalence de la maladie dans les familles des diabétiques fut comparée avec celle des sujets de contrôle (rapportK) — méthode souvent employée actuellement afin de déterminer le mode de transmission du diabète — nous nous sommes trouvés en face de certains problèmes qui sembleraient indiquer que cette méthode d'analyse génétique pourrait mener à certaines erreurs d'interprétation dans les maladies telles que le diabète. — Pour les raisons examinées, nous concluons que des différences dans les rapports de prévalence ne peuvent pas être acceptées comme preuves convaincantes d'un mode de transmission différent du diabète juvénile et du diabète d'apparition plus tardive.
    Abstract: Zusammenfassung Die Hypothese eines unterschiedlichen Vererbungsmodus für den Diabetes mit frühzeitiger Krankheitsmanifestation und den Diabetes mit späterem Krankheitsausbruch wurde auf Grund von Familienuntersuchungen geprüft. Blutsverwandte 1. Grades von 735 Diabetikern wurden mit einer entsprechenden Kontrollgruppe von 514 Personen verglichen. Bei den Blutsverwandten der Patienten mit früher Diabetesmanifestation ist aus den Krankheitsanamnesen und mündlichen Berichten eine größere Diabeteshäufigkeit zu ermitteln. Wenn indessen die scheinbar normalen Verwandten ersten Grades untersucht wurden, fand man eine große Anzahl vorher unbekannter Fälle von Glueosetoleranzstörung. Bei einem Vergleich der Diabeteshäufigkeit unter den Verwandten der Zuckerkranken und den Verwandten der Kontrollfälle (K Vergleichszahl) einer Methode, die z. Zt. oft zur Bestimmung des Vererbungsmodus benutzt wird, ergaben sich einige Probleme, die andeuten, daß diese Art Vererbungsanalysen bei Erkrankungen, wie dem Diabetes, irreführend sein können. Aus den Ergebnissen der Untersuchungen wird gefolgert, daß die zahlenmäßigen Unterschiede, die sich bei dieser Methode des Vergleichs ergeben, keinen Beweis für einen unterschiedlichen Vererbungsmodus des früher oder später sich manifestierenden Diabetes darstellen.
    Notes: Summary Suggestions that diabetes of younger- and older-onset are inherited differently have been examined in a family study which compares the first-degree relatives of 735 diabetic patients with those of 514 ‘control’ patients. Verbally reported histories from the propositi indicated an excess prevalence of known diabetes among the siblings of younger-onset diabetics; however, when the ostensibly normal, first-degree relatives were examined a high frequency of unsuspected glucose tolerance test abnormality was found. When the diabetes prevalence in relatives of diabetics was compared with that in relatives of controls (K ratio), a method at present widely used to determine the mode of inheritance, a number of problems arose suggesting that this means of genetic analysis may be misleading in diseases such as diabetes. It is concluded, for reasons which are discussed, that differences in prevalence ratios cannot be accepted as good evidence for different modes of inheritance of younger- and older-onset diabetes in man.
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  • 174
    ISSN: 1432-2072
    Keywords: Seizure ; Genetics ; Brain Amines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary DBA/2J mice, susceptible to audiogenic seizures, were found to be more susceptible to pentylenetetrazol- and electrically-induced seizures than either C57BL/6J or F1 hybrid mice, which are resistant to audiogenic seizures. Reserpine increased susceptibility to both pentylenetetrazol and electroconvulsive seizures in C57BL/6J, DBA/2J and F1 hybrid mice. 5-hydroxytrptophan, iproniazid and amino-oxyacetic acid decreased seizure susceptibility in all groups of mice. These results were interpreted to mean that DBA/2J mice are more susceptible to seizures than C57BL/6J or F1 hybrid mice regardless of the agents used to induce the seizures, and that levels of 5-HT, NE and GABA are important in determining seizure thresholds.
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  • 175
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    European archives of psychiatry and clinical neuroscience 211 (1968), S. 405-413 
    ISSN: 1433-8491
    Keywords: Symbiontic Psychoses (psychosis of association, folie à deux) ; Psychoses, Resembling Schizophrenia ; Genetics ; Symbiontische Psychosen (induzierte Psychosen, folie à deux, psychosis of association) ; Schizophrenieartige Psychosen ; Erbbiologie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Symbiontische Psychosen (induzierte Psychose, psychosis of association, folie à deux), die in psychoreaktiver Entwicklung unter dem Einfluß eines Primärpsychotischen zustande kommen, können oft einer schizophrenen Psychose ähnlich sehen. — Daß eine derartige Psychose erst bei gegebener genetischer Disposition entstehen kann, wird durch die erbbiologische Untersuchung nahe gelegt, die die hohe Schizophreniemorbidität in der Verwandtschaft auch der mit den Induzenten nicht blutsverwandten Induzierten erwiesen hat.
    Notes: Summary The psychopathological picture of symbiontic psychoses (psychosis of association, folie à deux), induced in a person as a psychic reaction to a primary psychotic, often resembles a psychosis of the schizophrenic type. Genetic studies have demonstrated a high morbidity of schizophrenia among the relatives of the induced subject, although there is no consangunity with the inducer. This suggests that symbiontic psychoses develop mainly in subjects with some genetic predisposition to schizophrenia.
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