AUTHOR=Zhao Shudi , Chen Guanping , Kong Xiangshuo , Chen Nan , Wu Xiaofeng 

TITLE=BmNPV p35 Reduces the Accumulation of Virus-Derived siRNAs and Hinders the Function of siRNAs to Facilitate Viral Infection

JOURNAL=Frontiers in Immunology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2022.845268

DOI=10.3389/fimmu.2022.845268

ISSN=1664-3224

ABSTRACT=<p>Antiviral immunity involves various mechanisms and responses, including the RNA interference (RNAi) pathway. During long-term coevolution, viruses have gained the ability to evade this defense by encoding viral suppressors of RNAi (VSRs). It was reported that <italic>p35</italic> of baculovirus can inhibit cellular small interference RNA (siRNA) pathway; however, the molecular mechanisms underlying <italic>p35</italic> as a VSR remain largely unclear. Here, we showed that <italic>p35</italic> of <italic>Bombyx mori</italic> nucleopolyhedrovirus (BmNPV) reduces the accumulation of virus-derived siRNAs (vsiRNAs) mapped to a particular region in the viral genome, leading to an increased expression of the essential genes in this region, and revealed that <italic>p35</italic> disrupts the function of siRNAs by preventing them from loading into Argonaute-2 (Ago2). This repressive effect on the cellular siRNA pathway enhances the replication of BmNPV. Thus, our findings illustrate for the first time the inhibitory mechanism of a baculovirus VSR and how this effect influences viral infection.</p>