Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Long telomeres in the polytene chromosomes of Drosophila melanogaster are associated with amplification of subtelomeric repeat sequences | Genet Sei Evol 1991 23 15-24 Elsevier INRA 15 Original article Long telomeres in the polytene chromosomes of Drosophila melanogaster are associated with amplification of subtelomeric repeat sequences ON Danilevskaya1 GE Lapta2 1 USSR Academy of Sciences Institute of Molecular Genetics 123182 Moscow 2 Kharkov State University Kharkov USSR Received 23 April 1990 accepted 7 November 1990 Summary - The T-32 strain of Drosophila melanogaster which was originally selected for heat resistance is characterized by having exceptionally long tips in chromosomes X and 2L in the poiytene salivary gland chromosomes. Six sublines differing in telomere length in different chromosomes were selected at an elevated temperature 32 C . The morphological characteristics of the telomeres in each subline are stable for a number of generations at 23 c. The additional chromatin in the long telomeres effectively hybridizes with a DNA sequence designated Dm665 which is related to the He-T family of heterochromatin- and telomere-associated sequences. The short telomeres show weak or no hybridization with the Dm665 fragment. This result implies that at least part of the morphological changes in telomere length in polytene chromosomes results from different degrees of amplification of the telomere-associated sequences. D melanogaster I polytene chromosome telomere length repeat sequence amplification Resume Les telomeres longs des chromosomes polytènes de Drosophila melanogaster sont associés à I amplification de sequences répétées subtélomériques. La souche T-32 de D melanogaster sélectionnée à I origine pour sa resistance à la chaleur se caractérise par des extrémités exceptionnellement allongées de ses chromosomes X et 2L chromosomes polytènes des glandes salivaires . Six sous-lignees differant par la longueur des telomeres de differents chromosomes ont élé sélectionnées à temperature élevée 32 C . Dans chacune des sous-lignées les caractéristiques des telomeres demeurent stables pendant .
