环状RNA的研究进展

doi:10.13560/j.cnki.biotech.bull.1985.2017-0009

摘要/Abstract

摘要： 环状RNA（Circular RNA，circRNA）是一类具有闭合环状结构的内源性非编码RNA（noncoding RNA，ncRNA），主要由前体RNA（pre-mRNA）通过可变剪切加工产生，circRNA广泛存在于所有真核生物中，并且非常稳定。目前，circRNA的研究已经成为了RNA研究领域的新热点，研究发现circRNA在转录本中占有相当大的比例，有的表达丰度甚至显著高于其他转录本。同时，circRNA对基因的表达有重要调控作用，在生物的发育进程中发挥了重要的生物学功能，如充当miRNA海绵、作为内源性RNA以及生物标记物，在疾病的诊断与治疗中也发挥重要作用。研究发现circRNA在一些疾病的发生中扮演了重要角色，包括动脉硬化、神经系统紊乱、糖尿病和癌症的发生。综述了circRNA的研究进展，阐述了circRNA的研究历史、circRNA的特点、形成过程、表达情况、circRNA与疾病间的关系以及circRNA的功能，并讨论了circRNA的研究意义及存在的问题。

关键词: 环状RNA, 非编码RNA, 可变剪切, RNA测序, 生物功能, 表达机制

Abstract: Circular RNA（circRNA）is a novel class of endogenous non-coding RNAs（ncRNA）with closed loop structure and is formed by alternative splicing from a precursor RNA（pre-mRNA）. Prior studies have discovered that circRNA widely and very stably exists in all eukaryotes. At present，the research of circRNA has become a new hotspot in the field of RNA research. It is found that circRNA accounts for a large proportion in transcripts，and some of the expressions are even higher than other transcripts. CircRNA plays a regulating role in gene expression，and an essential role in the process of biological development，such as miRNA sponges，endogenous RNAs and biomarkers，as well as critical role in the diagnosis and treatment of diseases. Some studies have revealed that circRNAs play key roles in the development of some diseases，including atherosclerosis，nerve system disorders，diabetes and cancers. In this paper，we review the research progress of circular RNA，including the characteristics of circRNA，the formation process，the expression，the relationship between circRNA and disease，as well as the function of circRNA. Moreover，we discuss the significance and existing problems in studying circRNA.

Key words: circRNA, non-coding RNA, alternative splicing, RNA sequencing, biological function, expression mechanism

张潆月,马月辉,赵倩君. 环状RNA的研究进展[J]. 生物技术通报, 2017, 33(7): 29-34.

ZHANG Ying-yue ,MA Yue-hui ,ZHAO Qian-jun. Study Progress on Circular RNA[J]. Biotechnology Bulletin, 2017, 33(7): 29-34.

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