The miR-3156-3p/K+ channel axis regulates replication and release of non-enveloped RNA viruses

Viruses rely on egress machinery for cell exit, which is crucial for their transmission. While non-enveloped RNA viruses, such as picornaviruses, are typically associated with the lytic release pathway, emerging evidence suggests they can also be packaged within vesicles for non-lytic release. However, the molecular mechanisms regulating this remain unclear. Here, we performed a genome-wide CRISPR-Cas9 screen and identified the microRNA hsa-miR-3156-1 as a critical host factor for picornavirus replication. Both the primary and mature forms of miR-3156-1 were upregulated following infection, with miR-3156-3p serving as a positive regulator of viral replication by directly targeting the 3′-untranslated regions of K+ channel-associated genes, KCNV1, KCNJ2, KCNK3, and KCNK5, causing plasma membrane depolarization and Ca2+ influx, which facilitate non-lytic release. Administration of a miR-3156-3p antagomir alleviated virus-associated acute flaccid paralysis in a mouse model. Our findings reveal how the miR-3156-3p/K+ channel regulatory axis regulates picornavirus release, highlighting potential therapeutic targets.