Cuenca J B, Galindo M I, Saura A O, Sorsa V, de Frutos R
Departament de Genética, Universitat de València, c/Dr. Moliner 50, E-46100-Burjassot, València, Spain.
Chromosoma. 1998 May;107(2):113-26. doi: 10.1007/s004120050287.
We have used a new approach involving in situ hybridisation and electron microscopy to establish ultrastructural homologies between polytene chromosome regions of Drosophila melanogaster and Drosophila subobscura. Twelve probes were chosen to cover all the chromosomal elements: the myospheroid gene, the collagen type IV gene, the collagen-like gene, the w26 homeobox gene, the beta3 tubulin gene, the kinesin heavy chain gene, the tryptophan hydrolase gene, the Hsp82, Hsp22-26 and Hsp23-28, Hsp68, Hsp70 genes and the beta unit of the F0-F1 ATPase gene. Most of these loci were previously undescribed in D. subobscura and imprecisely located in D. melanogaster. We have demonstrated here, by an ultrastructural analysis of each chromosomal region, that homologous genetic loci tend to show a similar ultrastructure in the two species. With a few exceptions, the structural homology extends to the chromosomal regions surrounding the loci. In some cases, however, no structurally recognisable homology can be seen either in the locus or in its flanking regions.
我们采用了一种涉及原位杂交和电子显微镜的新方法，以确定黑腹果蝇和 obscura 果蝇多线染色体区域之间的超微结构同源性。选择了12个探针来覆盖所有染色体元件：肌球样基因、IV 型胶原基因、类胶原基因、w26 同源框基因、β3 微管蛋白基因、驱动蛋白重链基因、色氨酸水解酶基因、Hsp82、Hsp22 - 26 和 Hsp23 - 28、Hsp68、Hsp70 基因以及 F0 - F1 ATP 酶基因的β亚基。这些位点中的大多数在 obscura 果蝇中以前未被描述，在黑腹果蝇中定位也不准确。我们通过对每个染色体区域的超微结构分析表明，同源基因座在这两个物种中往往表现出相似的超微结构。除了少数例外，结构同源性延伸到基因座周围的染色体区域。然而，在某些情况下，在基因座或其侧翼区域都看不到结构上可识别的同源性。
