AUTHOR=Liang Wenjuan , Zhou Li , Dang Zhuo , Wang Shiyuan , Zhao Ping , Xia Qingyou , Lu Zhongyan 

TITLE=Downregulation of BmSTAT transcription factor promoted nucleopolyhedrovirus replication in Bombyx mori

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1485951

DOI=10.3389/fmicb.2024.1485951

ISSN=1664-302X

ABSTRACT=<p>The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway plays a crucial role in the viral immune processes of organisms, with STAT being a key transcription factor downstream in this pathway. The <italic>STAT</italic> gene of <italic>Bombyx mori</italic> has two splicing forms, named <italic>BmSTAT-S</italic> and <italic>BmSTAT-L</italic>. This study compared the effects of the two splicing forms on <italic>Bombyx mori</italic> nucleopolyhedrovirus (BmNPV) infection through cell-level interference and further explored whether <italic>BmSTAT</italic> participates in the immune response to BmNPV infection via transgenic intervention at the individual level. Our research results indicated that BmNPV upregulates the expression of <italic>BmSTAT-S</italic> and <italic>BmSTAT-L</italic> in <italic>Bombyx mori</italic> BmE cells and larvae. Furthermore, BmE cells with interference of <italic>BmSTAT-S</italic> or <italic>BmSTAT-L</italic> displayed significantly higher expression levels of the viral gene <italic>GP41</italic> and increased viral fluorescence compared to the control group after 48 h of infection with BmNPV. Then, we constructed transgenic silkworms with genetic interference, and the results showed that both the transgenic silkworms with systemic interference and midgut-specific interference of the two splice forms of <italic>BmSTAT</italic> exhibited significantly reduced survival rates and increased viral replication numbers after infection with BmNPV. The above results indicated that the <italic>BmSTAT</italic> gene is involved in the immune response of <italic>Bombyx mori</italic> to BmNPV and these findings lay the foundation for further research on the mechanism of JAK/STAT signaling pathway involvement in BmNPV infection.</p>