Abstract

The flamenco locus is one of the main components of the piRNA pathway of regulation of mobile genetic elements (MGEs) in Drosophila melanogaster. Mutations at this locus lead to an increase in the transposition activity of MGEs and, as a result, to genetic instability. In this paper, the fertility of a genetically unstable MS strain obtained more than 25 years ago and characterized by a mutation in the flamenco locus and the presence of a functionally active copy of gypsy retrotransposon was investigated. Complex violations of the ovarian morphology were revealed in the MS strain in females: defects in the follicular layer and ring channels, as well as degradation of trophocytes, which in turn led to a decrease in reproductive abilities. Analysis of the MS strain transcriptome showed a decrease in the expression level of 40 genes encoding chorionic proteins and expression specificity at different stages of follicle development. In the F1 and F2 hybrid females from the crosses of MS females with wild type males, restoration of reproductive abilities was observed, despite the fact that half of the F2 females had the flamenco genotype and genetic instability caused by transposition of gypsy (according to the ovo^D test). Moreover, the frequency of gypsy transposition in the hybrid F2 females with the flamenco genotype doubled in comparison with the MS strain females. Thus, the MS strain had acquired partial suppression of the flamenco phenotype and accumulated several recessive mutations in the genes that control oogenesis after cultivation for over 25 years.

中文翻译：

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果蝇移动元件转座控制受损的果蝇MS菌株的育性研究

抽象

的弗拉门戈轨迹是移动遗传元件（MGES）的调节的piRNA基因途径的主要成分之一果蝇。在该基因座处的突变导致MGE的转座活性增加，结果导致遗传不稳定。在本文中，遗传上不稳定的MS菌株的繁殖力已超过25年前，其特征是弗拉门戈基因座发生突变，并且存在吉普赛人的功能活跃拷贝逆转录转座子进行了调查。女性的MS品系显示出复杂的卵巢形态侵犯：卵泡层和环通道的缺陷以及滋养细胞的降解，进而导致生殖能力的下降。MS菌株转录组的分析显示，在卵泡发育的不同阶段，编码绒毛膜蛋白的40个基因的表达水平和表达特异性均下降。在MS雌性与野生型雄性杂交的F1和F2杂种雌性中，观察到生殖能力的恢复，尽管事实是一半F2雌性具有弗拉门戈基因型和吉普赛易位引起的遗传不稳定（根据卵^D测试）。此外，具有弗拉门戈基因型的杂种F2雌性的吉普赛转位频率比MS雌性的两倍。因此，该MS菌株已经获得了弗拉门戈表型的部分抑制，并且在培养超过25年后的控制卵子发生的基因中积累了一些隐性突变。