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Activity of polytene chromosome puffs at the 0-hour prepupae stage and bioelectric properties of cellular nuclei of salivary glands were investigated under the influence of the hormone 20-OH-ecdysone in vitro in highly inbred selected lines LA (low activity) and HA (high activity) and their F1 hybrids LA x HA and Ha x LA. The inadaptive line LA differs from the line HA by the smaller size of the puffs. The hybrids exceed the best parental line by the size of the majority of the investigated puffs. In the course of investigation of F1 hybrids Ha x LA chromosomes the phenomenon of heteropuffing has been revealed at the asinapsis sites. In vitro impact of ecdysone increases the electrokinetic potential of cellular nuclei; in hybrids this effect expressed more strongly than in parental lines. The data obtained indicate genetic differences in puffing activity in Drosophila polytene chromosomes as a result of inbreeding, destabilizing selection and heterosis effect, and they also confirm the correlation of bioelectric properties of the nuclear genome with regulation of genetic activity of a cellular nucleus. 相似文献
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E. S. Belyaeva I. E. Vlassova Z. M. Biyasheva V. T. Kakpakov G. Richards I. F. Zhimulev 《Chromosoma》1981,84(2):207-219
Larvae homozygous or hemizygous for the l(l) t435 mutation located within the early ecdysteroid puff 2B5, or carrying a deletion of the 2B5 band, die at the end of the third larval instar. In the salivary gland chromosomes of these larvae only intermoult puffs are detected. If these salivary glands are incubated in vitro with 20-OH ecdysone for 6 h the intermoult puff 68 C remains large, some early puffs (74EF and 75B) are induced to 30–40% of their normal size, other early (63F) and all late puffs (62E, 78D, 82F and 63E) are not induced at all. Puff 2B5 reaches its normal size but does not regress after 6h incubation with 20-OH ecdysone, as it does in normal stocks. The data obtained in this study show the existence of a locus (or loci) in the band (puff) 2B5 which is necessary for the normal response of the salivary gland chromosomes to the hormone 20-OH ecdysone. 相似文献
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Continuous insect cell lines make a special object of research in biology. Insect cells in the established lines differ in the number of attributes from both normal differentiated, and embryonic cells. The period of genome destabilization necessarily precedes cell line immortalization. Genome destabilization is manifested by changes in genome size, cell karyotype, amplification of some retrotransposone families, and induction of their expression. The existence of significant genetic variability in one line puts a problem of searching for invariant attributes providing culture identification and defining the limits of normal polymorphism of cells in the culture. Using the vast collection of insect continuous cell lines stored at the N. I. Vavilov Institute of General Genetics RAS, nine lines were identified by RFLP method of mitochondrial DNA. Variability of DNA-polymorphisms, cellular karyology, morphology, immunological and biochemical attribute in the culture is discussed. 相似文献
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Derenko MV Maliarchuk BA Denisova GA Dambueva IK Kakpakov VT Dorzhu ChM Luzina FA Lotosh EA Ondar UN Kaplina MI Zakharov IA 《Genetika》2002,38(10):1409-1416
Using the data on mitochondrial DNA (mtDNA) polymorphism, genetic structures of the ethnic groups inhabiting South and East Siberia, including Altaians, Buryats, Tuvinians, Todjins, Tofalars, Yakuts, and Evenks were described. Mitochondrial gene pools of the populations examined were characterized by different ratios between Mongoloid (M*, C, D, E/G, G, A, B, and F) and Caucasoid (H, HV, I, J, K, T, U, and X) mtDNA lineages. All the populations studied carried a marked Mongoloid component, maximum frequency of which was observed in Evenks (92.4%) and Buryats (90.1%). Maximum frequencies of Caucasoid mtDNA lineages were detected in Tofalars (20.7%) and Yakuts (14.5%). Statistically significant interpopulation differences regarding the frequencies of mtDNA haplogroups were observed between all populations examined, excluding the pairs of Evenks-Yakuts, Evenks-Tuvinians, and Tuvinians-Todjins. Differentiation of the ethnic groups inhabiting South and East Siberia, as well as Central and Middle Asia, is discussed based on genetic, linguistic, and anthropological data. 相似文献
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Braude-Zolotarjova T. Ya. Kakpakov V. T. Schuppe N. G. 《In vitro cellular & developmental biology. Plant》1986,22(8):481-484
Summay A new established cell line 79f7Dv3g, ofDrosophila virilis consisting initially of male and female cells and represented now, after 6 yr of cultivation, only by male cells is described.
The population doubling time is 36 h at 25° C. The cell culture is also able to grow in serum-free media for an indefinite
time without special selection and has a population doubling time of 2 d. 相似文献
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Derenko M. V. Malyarchuk B. A. Denisova G. A. Dambueva I. K. Kakpakov V. T. Dorzhu Ch. M. Luzina F. A. Lotosh E. A. Ondar U. N. Kaplina M. I. Zakharov I. A. 《Russian Journal of Genetics》2002,38(10):1196-1202
Using the data on mitochondrial DNA (mtDNA) polymorphism, genetic structures of the ethnic groups inhabiting South and East Siberia, including Altaians, Buryats, Tuvinians, Todjins, Tofalars, Yakuts, and Evenks were described. Mitochondrial gene pools of the populations examined were characterized by different ratios between Mongoloid (M*, C, D, E/G, G, A, B, and F) and Caucasoid (H, HV, I, J, K, T, U, and X) mtDNA lineages. All the populations studied carried a marked Mongoloid component, maximum frequency of which was observed in Evenks (92.4%) and Buryats (90.1%). Maximum frequencies of Caucasoid mtDNA lineages were detected in Tofalars (20.7%) and Yakuts (14.5%). Statistically significant interpopulation differences regarding the frequencies of mtDNA haplogroups were observed between all populations examined, excluding the pairs of Evenks–Yakuts, Evenks–Tuvinians, and Tuvinians-Todjins. Differentiation of the ethnic groups inhabiting South and East Siberia, as well as Central and Middle Asia, is discussed based on genetic, linguistic, and anthropological data. 相似文献
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