As a defense mechanism against transposable elements,the PIWI-interacting RNA(piRNA)pathway maintains genomic integrity and ensures proper gametogenesis in gonads.Numerous factors are orchestrated to ensure normal ope...As a defense mechanism against transposable elements,the PIWI-interacting RNA(piRNA)pathway maintains genomic integrity and ensures proper gametogenesis in gonads.Numerous factors are orchestrated to ensure normal operation of the piRNA pathway.Spindle-E(Spn-E)gene was one of the first genes shown to participate in the piRNA pathway.In this study,we performed functional analysis of Spn-E in the model lepidopteran insect,Bombyx mori.Unlike the germline-specific expression pattern observed in Drosophila and mouse,BmSpn-E was ubiquitously expressed in all tissues tested,and it was highly expressed in gonads.Immunofluorescent staining showed that BmSpn-E was localized in both germ cells and somatic cells in ovary and was expressed in spermatocytes in testis.We used a binary transgenic CRISPR/Cas9 system to construct BmSpn-E mutants.Loss of BmSpn-E expression caused derepression of transposons in gonads.We also found that mutant gonads were much smaller than wild-type gonads and that the number of germ cells was considerably lower in mutant gonads.Quantitative real-time PCR analysis and TUNEL staining revealed that apoptosis was greatly enhanced in mutant gonads.Further,we found that the BmSpn-E mutation impacted gonadal development and gametogenesis at the early larval stage.In summary,our data provided the first evidence that BmSpn-E plays vital roles in gonadal development and gametogenesis in B.mori.展开更多
基金supported by grants from the National Natural Science Foundation of China(31530072,31830093,31601903,32102611)the Natural Science Foundation of Jiangsu Province(BK20210880).
文摘As a defense mechanism against transposable elements,the PIWI-interacting RNA(piRNA)pathway maintains genomic integrity and ensures proper gametogenesis in gonads.Numerous factors are orchestrated to ensure normal operation of the piRNA pathway.Spindle-E(Spn-E)gene was one of the first genes shown to participate in the piRNA pathway.In this study,we performed functional analysis of Spn-E in the model lepidopteran insect,Bombyx mori.Unlike the germline-specific expression pattern observed in Drosophila and mouse,BmSpn-E was ubiquitously expressed in all tissues tested,and it was highly expressed in gonads.Immunofluorescent staining showed that BmSpn-E was localized in both germ cells and somatic cells in ovary and was expressed in spermatocytes in testis.We used a binary transgenic CRISPR/Cas9 system to construct BmSpn-E mutants.Loss of BmSpn-E expression caused derepression of transposons in gonads.We also found that mutant gonads were much smaller than wild-type gonads and that the number of germ cells was considerably lower in mutant gonads.Quantitative real-time PCR analysis and TUNEL staining revealed that apoptosis was greatly enhanced in mutant gonads.Further,we found that the BmSpn-E mutation impacted gonadal development and gametogenesis at the early larval stage.In summary,our data provided the first evidence that BmSpn-E plays vital roles in gonadal development and gametogenesis in B.mori.