Research advances in circular RNAs / 中国组织工程研究

ABSTRACT

BACKGROUND:Unlike linear RNAs,circular RNAs (circRNAs) are a novel type of RNA which can form covalently closed circles and are highly expressed in eukaryotic transcriptomes.In the plenitude of naturally occurring RNAs,circRNAs and their biological role are underestimated for years.Recent studies have discovered thousands of endogenous circRNAs in mammalian cells.OBJECTIVE:To review the formation,properties,and functions of circRNAs,and their potential significance in diseases.METHODS:A computer-based search for literature in CNKI and PubMed databases published from January 2000 to December 2016 was performed using the keywords of "circRNA,miRNA,function,mechanism" in English and Chinese,respectively.Finally,62 eligible articles were included for analysis.RESULTS AND CONCLUSION:CircRNAs are largely generated from exonic or intronic sequences,and reverse complementary sequences or RNA-binding proteins are necessary for circRNA biogenesis.A majority of circRNAs that are conserved across specie are stable and resistant to RNaseR,and often exhibit tissue/developmental-stage-specific expression.Recent research has revealed that circRNAs can function as microRNA sponges,regulators of splicing and transcription,and modifiers of parental gene expression.Emerging evidence indicates that circRNAs might play important roles in atherosclerotic vascular diseases,neurological disorders,prion diseases and cancer;exhibit aberrant expression in colorectal cancer;and serve as diagnostic or predictive biomarkers of some diseases.Similar to microRNAs and long noncoding RNAs,circRNAs are arousing general interest in the field of RNA and widely participate in the life process.