Circular RNAs：鉴定、表达和功能

Circular RNAs:Identification,Expression and Function

随着第二代测序技术的发展,过去数十年功能性非编码RNA的种类不断增长。Circular RNAs(circRNA)是3’和5’端共价结合形成的一类环形RNA,表达广泛且丰度高。它们一般是由pre-mRNA经反式剪接(backsplicing)而形成的,即上游剪接受体与下游剪接供体结合。尽管对于circRNA的功能还没有定论,但是许多研究已表明许多真核生物均有circRNA的表达,并且在哺乳动物中具有保守性,但它们的调控方式与其同源线性RNA不同。研究表明circRNA呈发育调控、组织/细胞特异表达,并且所有真核生物均存在circRNA。这些特性表明circRNA或许具有重要功能。本文将重点探讨circRNA的经典实例、检测方法、功能作用。

With the development of second-generation sequencing technologies,the variety of functional non-coding RNAs has grown over the past few decades.Circular RNA（circRNA）are a group of noncoding RNAs that lack 5＇cap and 3＇poly（A）tail,which are widely expressed and abundant.They are formed by backsplicing of pre-mRNA,which means the upstream splice acceptor binds to a downstream splice donor.Although the function of circRNA has remained elusive,many studies demonstrated that many eukaryotes express the circRNA and it conserved in mammals.But the regulation of circRNA was totally different from homogenous linear RNA.Studies have shown that circRNA was expressed with developmentally regulated and tissue/cell specific,and existed in all eukaryotes.These characteristics suggest that circRNA may have important functions.This article will focus on the classic examples,detection methods,and functional roles of circRNA.