Abstract
The temporal order of replication of specific sites in polytene chromosomes from salivary glands and gastric caeca of Drosophila nasuta larvae was compared using 3H-thymidine autoradiography. Labelling of different cytological regions in segments of chromosome 2R (section 47 A to 49 C) and chromosome 3 (section 80 A to 82 C) was examined in detail in nuclei showing late S-period labelling (2 D and 1D types) in both cell types. The different labelling sites (22 on the 2R segment and 38 on the chromosome 3 segment) are cytologically similar in the two cell types. However, there are profound differences in the labelling frequencies of certain sites in polytene nuclei from salivary glands and gastric caeca during the late S-phase. This suggests that even though a comparable number of chromosomal replicating units operates in the two polytene cell types, the temporal order of completion of replication differs.
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References
Beermann W (1962) Riesenchromosomen. Plasmatologia. Band IVd, Springer, Vienna
Blumenthal AB, Kriegstein HJ, Hogness DS (1973) The units of DNA replication in Drosophila melanogaster chromosomes. Cold Spring Harbor Symp Quant Biol 38:19–41
Callan HG (1972) Replication of DNA in the chromosomes of eukaryotes. Proc R Soc Lond B 181:19–41
Farber RA, Davidson RL (1977) Differences in the order of termination of DNA replication in human chromosomes in peripheral blood lymphocytes and skin fibroblasts from the same individual. Cytogenet Cell Genet 18:349–363
Hägele K, Kalisch WE (1980) DNA Replication of a polytene chromosome section in Drosophila prior to an during puffing. Chromosoma 79:75–83
Laird CD (1980) Structural paradox of polytene chromosomes. Cell 22:869–874
Lakhotia SC, Sinha P (1983) Replication in Drosophila chromosomes. X. Two kinds of active replicons in salivary gland polytene nuclei and their relation to chromosomal replication patterns. Chromosoma 88:265–276
Mishra A, Lakhotia SC (1982) Replication in Drosophila chromosomes. Part VIII. Temporal order of replication of specific sites in polytene chromosomes from 24° C and 10° C reared larvae of D. melanogaster. Ind J Exp Biol 20:652–659
Pelling C (1966) A replicative and synthetic chromosomal unit: the modern concept of the chromomere. Proc R Soc Lond B 164:179–289
Redfern CPF (1981) DNA replication in polytene chromosomes: Similarity of termination patterns in somatic and germ-line derived polytene chromosomes of Anopheles Stephensi Liston (Diptera: Culicidae). Chromosoma 84:33–47
Rodman TC (1968) Relationship of developmental stage to initiation of replication in polytene nuclei. Chromosoma 23:271–287
Roy S, Lakhotia SC (1981) Replication in Drosophila chromosomes. Part IV. Patterns of chromosomal replication in salivary gland polytene nuclei of Drosophila nasuta. Ind J Exp Biol 19:797–807
Rudkin GT (1972) Replication in polytene chromosomes. In: (W. Beermann, ed.) Developmental studies on giant chromosomes. Springer: Berlin Heidelberg New York, pp 59–85
Sheldon S, Nichols WW (1981) Comparison of the patterns of chromosomal late replication. I. Human renal epithelium and lung fibroblasts in vitro. Cytogenet Cell Genet 29:40–50
Sinha P, Lakhotia SC (1980) Replication in Drosophila chromosomes. Part V. Polytene chromosome replication after in vitro culture of larval salivary glands. Ind J Exp Biol 18:1059–1065
Steinemann M (1981 a) Chromosomal replication in Drosophila virilis. II. Organization of active origins in diploid brain cells. Chromosoma 82:267–288
Steinemann M (1982) Chromosomal replication in Drosophila. III. Organization of active origins in highly polytene salivary gland cells. Chromosoma 82:289–307
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Lakhotia, S.C., Tiwari, P.K. Replication in Drosophila chromosomes. Chromosoma 89, 212–217 (1984). https://doi.org/10.1007/BF00295002
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DOI: https://doi.org/10.1007/BF00295002