Abstract
Covalent closed circular RNAs (circRNAs) can act as a bridge between non-coding RNAs and coding messenger RNAs. CircRNAs are generated by a back-splicing mechanism during post-transcriptional processing and are abundantly expressed in eukaryotic cells. CircRNAs can act via the modulation of RNA transcription and protein production, and by the sponging of microRNAs (miRNAs). CircRNAs are now thought to be involved in many different biological and pathological processes. Some studies have suggested that the expression of host circRNAs is dysregulated in several types of virus-infected cells, compared to control cells. It is highly likely that viruses can use these molecules for their own purposes. In addition, some viral genes are able to produce viral circRNAs (VcircRNA) by a back-splicing mechanism. However, the viral genes that encode VcircRNAs, and their functions, are poorly studied. In this review, we highlight some new findings about the interaction of host circRNAs and viral infection. Moreover, the potential of VcircRNAs derived from the virus itself, to act as biomarkers and therapeutic targets is summarized.
Highlights
Single-stranded circular RNAs (circRNAs) belong to the non−coding RNA family. Unlike linear RNAs, they are take the form of a covalently closed continuous loop with neither 5 capping nor 3 polyadenylation, and are formed by a backsplicing process (Guo et al, 2014; Holdt et al, 2018). Sanger et al (1976) originally discovered the presence of circRNAs in a viroidinfected plant using electron microscopy in 1970
Single-stranded circular RNAs belong to the non−coding RNA family
The results showed that the expression levels of 536 separate circRNAs were significantly dysregulated after herpes simplex virus (HSV)-1 infection, and of these, 348 circRNAs were down-regulated and 188 were up-regulated
Summary
Single-stranded circular RNAs (circRNAs) belong to the non−coding RNA family. Unlike linear RNAs, they are take the form of a covalently closed continuous loop with neither 5 capping nor 3 polyadenylation, and are formed by a backsplicing process (Guo et al, 2014; Holdt et al, 2018). Sanger et al (1976) originally discovered the presence of circRNAs in a viroidinfected plant using electron microscopy in 1970. Up to now only a few studies have been performed on the function of circRNAs in viral infections, and the role they may play in inhibiting or enhancing virus replication is not well understood. It is not yet clear whether the aberrant expression of circRNAs in virus-infected cells, contributes to viral replication or not.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
