Functional analysis of the orphan genes Tssor-3 and Tssor-4 in male Plutella xylostella

• 作者: LI Tian-pu ZHANG Li-wen LI Ya-qing YOU Min-sheng ZHAO Qian
• 来源期刊: 农业科学学报（英文版）
• 年，卷（期）: 2021,（7）
• 所属期刊栏目: Plant Protection
• 页码范围: 1880-1888
• 页数: 9页
• 语种: 英文
• DOI: 10.1016/S2095-3119(21)63655-9

摘要

Orphan genes are genes with no sequence homologues in other species. Here, we identified two orphan genes, namely, Tssor-3 and Tssor-4, in Plutella xylostella. Both genes contained a signal peptide sequence, suggesting their functions as secreted proteins. Expression pattern analysis based on real-time quantitative PCR (qPCR) showed that both orphan genes were specifically expressed in all male gonads except the testes. The expression of both the orphan genes peaked at the male adult stage. Immunofluorescence assays suggested that the two proteins were seminal proteins, indicating their potential roles in male reproductive regulation. To further explain their functions, we knocked down the expression of these two genes by RNA interference (RNAi). The results showed that the expression of Tssor-3 and Tssor-4 was significantly downregulated at 24 h after injection compared to that of the controls. Biological assays showed that the number of laid eggs and the hatching rate of offspring eggs were significantly reduced when the expression of Tssor-3 and Tssor-4 was reduced, suggesting that the two orphan genes played a role in male fertility in P. xylostella. Our results provide evidence that orphan genes are involved in male reproductive regulation, which is important for male fitness during evolution.