Sex determination pathways are astoundingly diverse in insects. For instance, the silk moth Bombyx mori uniquely use various components of the piRNA pathway to produce the Fem signal for specification of the female fate. In this study, we identified BmGTSF1 as a novel piRNA factor which participates in B. mori sex determination. We found that BmGtsf1 has a distinct expression pattern compared to Drosophila and mouse. CRISPR/Cas9 induced mutation in BmGtsf1 resulted in partial sex reversal in genotypically female animals by shifting expression of the downstream targets BmMasc and Bmdsx to the male pattern. As levels of Fem piRNAs were substantially reduced in female mutants, we concluded that BmGtsf1 plays a critical role in the biogenesis of the feminizing signal. We also demonstrated that BmGTSF1 physically interacted with BmSIWI, a protein previously reported to be involved in female sex determination, indicating BmGTSF1 function as the cofactor of BmSIWI. BmGtsf1 mutation resulted in piRNA pathway dysregulation, including piRNA biogenesis defects and transposon derepression, suggesting BmGtsf1 is also a piRNA factor in the silkworm. Furthermore, we found that BmGtsf1 mutation leads to gametogenesis defects in both male and female. Our data suggested that BmGtsf1 is a new component involved in the sex determination pathway in B. mori.

昆虫中的性别决定途径令人惊讶地多样。例如，蚕蛾Bombyx mori独特地使用piRNA途径的各种成分来产生Fem信号，以明确女性的命运。在这项研究中，我们确定BmGTSF1为参与B的新型piRNA因子。家蚕性别决定。我们发现与果蝇和小鼠相比，BmGtsf1具有独特的表达模式。CRISPR / Cas9诱导的BmGtsf1突变通过改变下游靶标BmMasc和Bmdsx的表达而导致基因型雌性动物的部分性别逆转到男性模式。由于Fem piRNA的水平在女性突变体中显着降低，因此我们得出结论，BmGtsf1在女性信号的生物发生中起关键作用。我们还证明了BmGTSF1与BmSIWI发生物理相互作用，BmSIWI是一种以前据报道参与女性性别确定的蛋白质，表明BmGTSF1作为BmSIWI的辅助因子起作用。BmGtsf1突变导致piRNA途径失调，包括piRNA生物发生缺陷和转座子抑制，表明BmGtsf1也是家蚕中的piRNA因子。此外，我们发现BmGtsf1突变导致男性和女性的配子发生缺陷。我们的数据表明BmGtsf1是B中性别决定途径涉及的新成分。森。