AUTHOR=Huang Ying , Han Keke , Wang Wen , Ren Qian 

TITLE=Host MicroRNA-217 Promotes White Spot Syndrome Virus Infection by Targeting Tube in the Chinese Mitten Crab (Eriocheir sinensis)

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=7

YEAR=2017

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2017.00164

DOI=10.3389/fcimb.2017.00164

ISSN=2235-2988

ABSTRACT=<p>MicroRNAs (miRNAs), a group of small molecule non-encoding RNAs, are key post-transcriptional regulators of gene expression that are implicated in many biological processes. In the current study, miR-217 from <italic>Eriocheir sinensis</italic> was selected for studying its roles during host–virus interaction. Overexpression or silencing of miR-217 led to considerable effects on white spot syndrome virus (WSSV) replication, implying that miR-217 played a positive role in WSSV infection. In insect High Five cells, miR-217 significantly inhibited <italic>Tube</italic> gene expression by binding to the 3′-untranslated region of the <italic>Tube</italic>. Overexpression of miR-217 in crab led to downregulation of <italic>tube</italic> expression. Knockdown of <italic>Tube in vivo</italic> led to significant enhancement of WSSV infection and inhibited the expression of five <italic>antimicrobial peptide</italic> (<italic>AMP</italic>) genes (<italic>Anti-lipopolysaccharide factor ALF1, ALF2, ALF3</italic>; <italic>Crustin Crus1, Crus2</italic>) in WSSV-challenged crabs. Overexpression of miR-217 also led to downregulation of these <italic>AMP</italic> genes in WSSV-challenged crabs. Our results showed that host miRNA played positive roles in virus infection by regulation of host <italic>tube</italic> gene, which is the key component of Toll signaling pathway.</p>