Circular RNAs (circRNAs) represent a large class of noncoding RNAs (ncRNAs) that 
have recently emerged as regulators of gene expression. They have been shown to 
suppress microRNAs, thereby increasing the translation and stability of the 
targets of such microRNAs. In this review, we discuss the emerging functions of 
circRNAs, including RNA transcription, splicing, turnover, and translation. We 
also discuss other possible facets of circRNAs that can influence their function 
depending on the cell context, such as circRNA abundance, subcellular 
localization, interacting partners (RNA, DNA, and proteins), dynamic changes in 
interactions following stimulation, and potential circRNA translation. The 
ensuing changes in gene expression patterns elicited by circRNAs are proposed to 
drive key cellular processes, such as cell proliferation, differentiation, and 
survival, that govern health and disease. WIREs RNA 2017, 8:e1386. doi: 
10.1002/wrna.1386 For further resources related to this article, please visit 
the WIREs website.