circRNA作用机制及其对动物肌肉发育的影响

Mechanism of circRNA and Its Effect on Development of Animal Muscles

circRNA是一种不具有5′端帽子结构和3′端多聚(A)尾巴结构但能稳定存在于真核细胞内的非编码RNA(ncRNA),是经过反向剪接构成的闭合环状分子,为近年来的研究热点。越来越多的研究已证明,circRNA对生物体的各种生命活动发挥着极其重要的调控作用。根据组成不同,circRNA可分为外显子环状、内含子环状及内含子外显子共同组成的环状。同时circRNA功能的发挥依赖于其细胞定位,位于细胞核的circRNA主要在基因转录水平与RNA聚合酶Ⅱ结合调控寄主基因的转录活性;而位于细胞液中的circRNA主要发挥竞争性内源RNA的作用,通过竞争性抑制miRNA与靶基因mRNA 3′UTR的结合,发挥其对miRNA和靶基因的调控作用;circRNA还可翻译成蛋白质或多肽。目前,circRNA在畜禽肌肉生长发育方面的相关研究还处于起步阶段,主要是关于circRNA作为竞争性内源RNA发挥重要调控功能。文章就circRNA的发现、分类、生成机制、作用方式及对动物肌细胞增殖和分化的前沿研究作一简要阐述,并提出circRNA对畜禽肌肉功能研究的展望,以期为今后circRNA相关功能的研究提供参考。

circRNA is a non-coding RNA（ncRNA）that does not have a 5′end cap structure and3′end poly（A）tail structure but can stably exist in eukaryotic cells.circRNA that formed by reverse splicing is the hottest ncRNA in the past few years.Much more researches have proved that circRNA plays an extremely important regulatory roles in the life activities of organisms.According to the different composition,circRNA can be divided into exon candidates,intron candidates and candidates of the intron-exons.In addition,the function of circRNA depended on its cellular site-specification.circRNA located in the nucleus always regulates the transcriptional activity of hosting genes mainly at gene transcriptional level with RNA polymeraseⅡ;circRNA in the cytoplasm plays a major function in the role of competitive endogenous RNA,and mainly competitive inhibition of miRNA and their target 3′UTR to regulate the expression levels of miRNA and their targets;Recent studies have shown that circRNA can also be translated into proteins or peptides.At present,the related circRNA research on animal muscle growth and development is still at the initial stage,and the related research is mainly about circRNA as a competitive endogenous RNA to play an important regulatory role.This paper summarized the discovery,classification,produc-tion mechanism,mode of action of circRNA and its effect on myocyte proliferation and differentiation in recent years.Finally,we proposed a prospective study of circRNA on muscle growth and development,and we hope our research could offer some useful experience for other researches.