Dorer D R, Ezekiel D H, Christensen A C
Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107-5541, USA.
Genetics. 1995 Nov;141(3):1037-42. doi: 10.1093/genetics/141.3.1037.
In the genome of Drosophila melanogaster there is a single locus, Triplo-lethal (Tpl), that causes lethality when present in either one or three copies in an otherwise diploid animal. Previous attempts to mutagenize Tpl produced alleles that were viable over a chromosome bearing a duplication of Tpl, but were not lethal in combination with a wild-type chromosome, as deficiencies for Tpl are. These mutations were interpreted as hypomorphic alleles of Tpl. In this work, we show that these alleles are not mutations at Tpl; rather, they are dominant mutations in a tightly linked, but cytologically distant, locus that we have named Suppressor-of-Tpl (Sul(Tpl)). Su(Tpl) mutations suppress the lethality associated with three copies of the Triplo-lethal locus and are recessive lethal. We have mapped Su(Tpl) to the approximate map position 3-46.5, within the cytological region 76B-76D.
在黑腹果蝇的基因组中，有一个单一基因座，三倍体致死基因（Tpl），当它在二倍体动物中以单拷贝或三拷贝存在时会导致致死。之前诱变Tpl的尝试产生了一些等位基因，这些等位基因在携带Tpl重复的染色体上是存活的，但与野生型染色体组合时并不像Tpl缺失那样具有致死性。这些突变被解释为Tpl的亚效等位基因。在这项研究中，我们表明这些等位基因并非Tpl的突变；相反，它们是在一个紧密连锁但细胞学上距离较远的基因座中的显性突变，我们将这个基因座命名为Tpl抑制基因（Sul(Tpl)）。Su(Tpl)突变抑制了与三倍体致死基因座的三个拷贝相关的致死性，并且是隐性致死的。我们已将Su(Tpl)定位到大约3-46.5的图谱位置，位于细胞学区域76B-76D内。
