Viral miRNAs confer survival in host cells by targeting apoptosis related host genes

Abstract

miRNAs are small non-coding RNAs that regulate gene expression by RNA silencing. Like eukaryotic organisms, some viruses also produce miRNAs. While contribution of host miRNA in preventing viral pathogenesis has been studied, how viral miRNA confers survival within the host is poorly understood. Here, we hypothesize that viral miRNAs confer pathogenicity by binding to host target genes to down-regulate specific pathways that threaten cell survival. In order to identify such pathways, we performed functional enrichment analysis using targets of 168 viral miRNAs from 13 different viruses. We identified specific immune system and host defense pathways targeted by viruses via miRNA mediated gene silencing. Analysis and integration of publicly available RNA-seq data revealed that viruses target the apoptosis in the host by switching off pro-apoptotic genes through miRNA-induced mechanisms, thus ensuring cell survival. In conclusion, our findings reveal an important function of viral miRNA in downregulating host apoptosis machinery.

Keywords

• miRNA
• Viral pathogenesis
• Apoptosis
• Functional enrichment
• Immune system