Fig. 1

The functions of circRNAs. Four modes of circRNA functions are shown in the picture. a CircRNAs can act as miRNA sponges by competing for the binding of miRNA sequences, and mitigating the impact of miRNA-mediated regulation on gene expression. b CircRNAs can interact with proteins, by binding to other RNA-binding proteins (RBPs). c CircRNAs (EIciRNAs and CiRNAs) can enhance the expression of its parent genes through the formation of transcription complexes. d CircRNAs can be translated to create functional proteins