Overview of circRNA Functions Discovered Thus Far
circRNAs can act as (A) miRNA sponge, (B) protein sponge, (C) protein decoy, and (D) scaffold for the formation of protein complexes. (E) A few circRNAs were shown to encode small peptides. (F) Candidates from subclasses of circular transcripts, ciRNAs and EIciRNAs, were shown to regulate parental gene expression. (G) By a thus far unknown mechanism, circRNAs are released from cells and can be detected in serum, plasma, and exosomes.