A Protein Asteroid with PIN Domain in Silkworm Is Involved in Anti-BmNPV Infection.

Nuclease is a type of protein that degrades nucleic acids, which plays an important role in biological processes, including RNA interference efficiency and antiviral immunity. However, no evidence of a link between nuclease and nucleopolyhedrovirus (BmNPV) infection in silkworm has been found. In this study, a protein asteroid (BmAst) containing the PIN domain and XPG domain was identified in silkworm . gene was highest expressed in hemocytes and fat body of the 5th instar larvae, and high expression in the pupa stage. The transcriptional levels of the gene in 5th instar larvae were significantly induced by BmNPV or dsRNA. After knocking down gene expression by specific dsRNA, the proliferation of BmNPV in was increased significantly, whereas the survival rate of larvae was significantly lower when compared with the control. Our findings indicate that BmAst is involved in silkworm resistance to BmNPV infection.