Two types of genetic interaction implicate the whirligig gene of Drosophila melanogaster in microtubule organization in the flagellar axoneme.
Two types of genetic interaction implicate the whirligig gene of Drosophila melanogaster in microtubule organization in the flagellar axoneme.
复制标题
两种类型的遗传相互作用表明果蝇鞭毛轴丝微管组织中的旋转基因。
DOI：
10.1093/genetics/126.4.961
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发表时间：
1990
期刊：
影响因子：
3.3
通讯作者：
Fuller,MT
中科院分区：
文献类型：
--
作者：
Green,LL;Wolf,N;McDonald,KL;Fuller,MT
果蝇Whirrigig(3-54.4)的NC4突变等位基因不能补充α-微管蛋白基因座α1t的突变、β-微管蛋白基因座B2t的突变或haywire基因座的突变。然而，WRL未能映射到任何已知的α-或β-微管蛋白基因。基因外的补体失败可能表明WRL产物参与了与微管蛋白的结构相互作用。旋转性基因座似乎是男性生育能力的单倍体不足。在微管蛋白的遗传背景中，Wr1的缺失和通过逆转WrlnC4和B2Tn之间的互补性失败而可能获得的功能等位基因的丧失都是显性雄性不育。如果果蝇也是B2Tn杂合子、阿尔法1T缺乏症或haync2等位基因杂合子，则恢复等位基因的显性雄性不育性被抑制。这些结果表明，WRL基因产物的绝对水平不是影响正常精子发生的重要因素，而是与微管或微管功能相关的水平。纯合子的Wrl突变体的表型表明，旋转蛋白产物在精子细胞减数分裂后的分化中发挥作用，可能是在组织精子鞭毛轴丝的微管。Wlnc4或恢复等位基因纯合的果蝇是有活力的，雌性是可育的，但雄性是不育的。精子发生的减数分裂前和减数分裂阶段似乎是正常的。但在减数分裂后，鞭毛轴丝表现为外偶微管B亚纤维上的副微管丢失，外三联体代替外偶微管，中央对微管缺失。
The mutant nc4 allele of whirligig (3-54.4) of Drosophila melanogaster fails to complement mutations in an alpha-tubulin locus, alpha 1t, mutations in a beta-tubulin locus, B2t, or a mutation in the haywire locus. However, wrl fails to map to any of the known alpha- or beta-tubulin genes. The extragenic failure to complement could indicate that the wrl product participates in structural interactions with microtubule proteins. The whirligig locus appears to be haploinsufficient for male fertility. Both a deficiency of wrl and possible loss of function alleles obtained by reverting the failure to complement between wrlnc4 and B2tn are dominant male sterile in a genetic background wild type for tubulin. The dominant male sterility of the revertant alleles is suppressed if the flies are also heterozygous for B2tn, for a deficiency of alpha 1t, or for the haync2 allele. These results suggest that it is not the absolute level of wrl gene product but its level relative to tubulin or microtubule function that is important for normal spermatogenesis. The phenotype of homozygous wrl mutants suggests that the whirligig product plays a role in postmeiotic spermatid differentiation, possibly in organizing the microtubules of the sperm flagellar axoneme. Flies homozygous for either wrlnc4 or revertant alleles are viable and female fertile but male sterile. Premeiotic and meiotic stages of spermatogenesis appear normal. However, in post-meiotic stages, flagellar axonemes show loss of the accessory microtubule on the B-subfiber of outer doublet microtubules, outer triplet instead of outer doublet microtubules, and missing central pair microtubules.