Roles and Applications of Circular RNA in Virus Infection.

Circular RNAs (circRNAs) are novel types of covalently closed single-stranded RNA formed by the backsplicing of precursor mRNAs (pre-mRNAs). Recently, circRNAs have been shown to play a crucial role in various diseases, including cancers, cardiovascular and cerebrovascular diseases, and autoimmune diseases. Accumulating evidence has demonstrated that both host-derived and virus-encoded circRNAs play pivotal roles during viral infection, including modulating viral entry, genome replication, latency establishment, and the host antiviral immune responses while simultaneously facilitating viral immune evasion. However, their roles during viral infections and circRNA-host interactions remain to be further investigated. Therefore, this article reviews the key characteristics and biological functions of circRNAs, as well as recent advances in understanding the interactions between circRNAs from different sources and viral infections, which will offer insights for developing therapies targeting virus-associated diseases.