Research advances in circular RNAs

doi:10.3969/j.issn.2095-4344.2017.36.027

Abstract

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 signi?cance 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-speci?c expression. Recent research has revealed that circRNAs can function as microRNA sponges, regulators of splicing and transcription, and modi?ers 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.

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

Key words: MicroRNAs, Exons, Introns, Tissue Engineering

CLC Number:

R318

Cheng Han-rong1, 2, 3, He Shao-ru2, 3, Wu Ben-qing1. Research advances in circular RNAs[J]. Chinese Journal of Tissue Engineering Research, 2017, 21(36): 5898-5904.

Figures/Tables 2

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