The unusual spectrum of mutations induced by hybrid dysgenesis at the Triplo-lethal locus of Drosophila melanogaster.
The unusual spectrum of mutations induced by hybrid dysgenesis at the Triplo-lethal locus of Drosophila melanogaster.
复制标题
果蝇三倍致死基因座杂交发育不全诱导的不寻常突变谱。
DOI：
10.1093/genetics/125.4.795
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发表时间：
1990
期刊：
影响因子：
3.3
通讯作者：
Christensen,AC
中科院分区：
文献类型：
--
作者：
Dorer,DR;Christensen,AC
三倍致死基因座 (Tpl) 的剂量敏感性是独一无二的；果蝇中没有发现其他基因座在三种剂量下存在时是致命的。 Tpl也是单倍致死的，其功能仍然是个谜。之前的研究人员发现，除了完全删除 Tpl 所在的染色体区域 (83DE) 之外，几乎不可能通过突变使 Tpl 失活。我们利用 P-M 杂种发育不全来努力获得 Tpl 的新突变。我们恢复了 19 个新的 Tpl 重复、15 个 Tpl 亚等位突变（以前罕见的一类突变），并且没有无效突变。令人惊讶的是，15 个亚等位基因中有 14 个在该位点没有可检测到的 P 元件序列。恢复 Tpl 无效突变的困难表明它可能是一个复杂的基因座，可能由几个具有冗余功能的基因组成。我们恢复亚等位基因的相对容易性与其他人之前诱变 Tpl 的尝试形成鲜明对比。与辐射或化学物质相比，杂交发育不全的突变率更高，这也表明该基因座具有特殊的遗传组织。
The Triplo-lethal locus (Tpl) is unique in its dosage sensitivity; no other locus in Drosophila has been identified that is lethal when present in three doses. Tpl is also haplo-lethal, and its function is still a mystery. Previous workers have found it nearly impossible to mutationally inactive Tpl other than by completely deleting the chromosomal region in which Tpl resides (83DE). We have utilized P-M hybrid dysgenesis in an effort to obtain new mutations of Tpl. We recovered 19 new duplications of Tpl, 15 hypomorphic mutations of Tpl (a previously rare class of mutation), and no null mutations. Surprisingly, 14 of the 15 hypomorphic alleles have no detectable P element sequences at the locus. The difficulty in recovering null mutations in Tpl suggests that it may be a complex locus, perhaps consisting of several genes with redundant functions. The relative ease with which we recovered hypomorphic alleles is in sharp contrast to previous attempts by others to mutagenize Tpl. A higher mutation rate with hybrid dysgenesis than with radiation or chemicals also suggests a peculiar genetic organization for the locus.