Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • transposable elements  (3)
  • Key words Prefrontal cortex  (1)
  • Prunus cerasus  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Presence of an Activator (Ac)-like sequence in Pennisetum glaucum (pearl millet) (1990)
    Springer
    Plant molecular biology 15 (1990), S. 177-179 
    Details
    ISSN: 1573-5028
    Keywords: pearl millet (Pennisetum glaucum) ; Poaceae ; transposable elements ; Activator (Ac)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00017740
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The α-2a noradrenergic agonist, guanfacine, improves delayed response performance in young adult rhesus monkeys (1998)
    Springer
    Psychopharmacology 136 (1998), S. 8-14 
    Details
    ISSN: 1432-2072
    Keywords: Key words Prefrontal cortex ; Memory ; Guanfacine ; Norepinephrine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In aged monkeys with naturally occurring catecholamine depletion, α-2 adrenergic agonists such as guanfacine have repeatedly been shown to improve dorsolateral prefrontal cortical function, as assessed by the spatial delayed response task. Both low (0.0001–0.001 mg/kg) and high (0.5 mg/kg) but not intermediate (0.01–0.05 mg/kg) doses of guanfacine improve spatial working memory performance in aged animals. However, it is not known whether guanfacine would similarly improve performance in young animals. In the present study, the effects of guanfacine on delayed response performance were characterized in seven young adult rhesus monkeys. Low doses of guanfacine (0.0001–0.01 mg/kg) had no effect on task performance, while high doses of guanfacine (0.1–0.7 mg/kg) significantly improved task performance. The highest doses produced mild sedation that was independent of drug effects on delayed response. The most effective dose of guanfacine was challenged with the α-2 antagonist idazoxan (0.1 mg/kg). This dose of idazoxan had no effect on task performance when given alone. Consistent with an α-2 mechanism, idazoxan significantly decreased delayed response performance in guanfacine-treated animals. These results support the hypothesis that delayed response performance in young intact animals can be improved through actions at α-2 adrenergic receptors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002130050533
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Morphological variation within a sour cherry collection (1991)
    Springer
    Euphytica 52 (1991), S. 47-55 
    Details
    ISSN: 1573-5060
    Keywords: Prunus cerasus ; sour cherry ; morphology ; germplasm collection ; genebank ; variation ; principal component analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Morphological traits of 28 full-sib sour cherry (Prunus cerasus L.) families developed with pollen from European sour cherry selections were evaluated with principal component (PC) analysis. The traits which loaded on the first PC were size characters such as lateral length, leaf area, fruit weight, and trunk diameter increase. These character loading on the first PC could be interpreted as representing gradations between morphologies characteristic of the 2 presumed progenitor species, sweet cherry (P. avium L.) and ground cherry (P. fruticosa Pall.). Mean family differences in trunk diameter increase, lateral length, leaf area, and fruit weight varied approximately 12, 3.7, 2.5, and 2 fold, respectively. These results suggest that it may be possible to select sour cherry hybrids approaching the tree and fruit size of either progenitor species. The results are discussed in reference to germplasm collection and the potential of certain cultivars and hybrids as parents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00037856
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Analysis of hexamer and pentamer motifs within a maize database: the presence of motif ‘signatures’ in functional gene categories (1999)
    Springer
    Genetica 105 (1999), S. 19-29 
    Details
    ISSN: 1573-6857
    Keywords: Ac transposase binding site ; functional gene categories ; genomics ; hexamer ; maize ; motif signatures ; nonrandom distributions ; pentamer ; repeat motifs ; Tourist motif ; transposable elements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Several transposable elements (TEs) have been reported in association with genes in maize and other plants. In this study we found, based on statistical analyses of 951 DNA sequences within a maize computer database, that short hexamer and pentamer DNA motifs from the Activator (Ac) and from the Tourist TEs, respectively, were also associated with maize genes. Moreover, these two short hexamer and pentamer TE motifs were nonrandomly and nearly nonrandomly distributed, respectively, with respect to particular biochemical functions of those maize genes. To determine whether this distribution may be unique to TE motifs, or may be more widespread among hexamers/pentamers in general, we similarly studied six additional hexamer or pentamer sequences not derived from TEs. These also showed nonrandom distribution with respect to functional gene categories in the maize database. However, each of the total of eight short sequence motifs we studied differed in its pattern of association with distinct sets of functional gene categories; that is, there was a unique ‘signature’ for each of the hexamers and pentameters tested. Potential biological hypotheses to explain these findings are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003559310976
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Molecular evolutionary characterization of an Activator (Ac)-like transposable element sequence from pearl millet (Pennisetum glaucum) (Poaceae) (1994)
    Springer
    Genetica 92 (1994), S. 77-89 
    Details
    ISSN: 1573-6857
    Keywords: Ac ; pearl millet ; transposable elements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We present data on the evolution of the Ac/Ds family of transposable elements in select grasses (Poaceae). A defective Ac-like element was cloned from a DNA library of the grass Pennisetum glaucum (pearl millet) and its entire 4531 bp sequence has been determined. When the pearl millet Ac-like sequence is aligned with the maize Ac sequence, it is found that there is approximately 70% DNA similarity in the central region spanning most of maize Ac exon II and all of exon III. In addition, there are two smaller regions of similarity at the Ac terminii. Besides these three major structural similarities, Pennisetum Ac has two large regions, one 5′ and one 3′, that show little similarity to Zea Ac. Furthermore, most of the sequences corresponding to intron II in maize Ac are absent in pearl millet Ac. Kimura's evolutionary distance between the central region of maize and pearl millet Ac sequences is estimated to be 0.429±0.020 nucleotide substitutions per site. This value is not significantly different from the average number of synonymous substitutions for coding regions of the Adh1 gene between maize and pearl millet, which is 0.395±0.051 nucleotide substitutions per site. If we assume Ac and Adh1 divergence times are equivalent between maize and pearl millet, then the above calculations suggest Ac-like sequences have probably not been strongly constrained by natural selection. Conserved DNA and amino acid sequence motifs are also examined. The level of DNA sequence divergence between maize and pearl millet Ac sequences, the estimated date when maize and pearl millet diverged (25–40 million years ago), coupled with their reproductive isolation/lack of current genetic exchange, all support the theory that Ac-like sequences have not been recently introduced into pearl millet from maize. Instead, Ac-like sequences were probably present in the progenitor of maize and pearl millet and have thus existed in the grasses for at least 25 million years.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00163756
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...