Bai Yuhe, Ding Xinyu, Liu Zezhong, Shen Junfei, Huang Yong
College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China.
College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China.
Comp Biochem Physiol Part D Genomics Proteomics. 2022 Jun;42:100969. doi: 10.1016/j.cbd.2022.100969. Epub 2022 Feb 5.
Circular RNA (circRNA) is a novel emerging type of endogenous regulatory non-coding RNA molecules with a covalent closed-loop configuration, which exerts important functions in multiple biological processes. CircRNAs are known to regulate gene expression as functional regulators interacting with miRNAs by sponge, which have been reported to regulate skeletal muscle development. Nevertheless, the information of circRNAs involved in regulating muscle growth and development in fish is largely unknown. Here, we first identified 312 and 511 circRNAs in skeletal muscle of juvenile and adult largemouth bass (LMB) using RNA sequencing, respectively. The differentially expressed circRNAs (DE-circRNAs) analysis showed that there are 44 DE-circRNAs at two different skeletal muscle growth stages. Six circRNAs were chosen randomly and their relative expression levels in juvenile and adult LMB were confirmed by real-time PCR, indicating that these circRNAs were existed authenticity. In addition, Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis showed that these hose genes (their linear mRNAs) of DE-circRNAs were mainly enriched in the regulation of actin cytoskeleton signaling pathways. The circRNA-miRNA interaction regulatory networks indicated that one circRNA can regulate one or more miRNA. For instance, more than 30 miRNAs were regulated by two circRNAs (circRNA389 and circRNA399). Of them, the muscle-related miRNAs including the let-7 family, miR-133 and miR-26 and so on were found acting as miRNAs sponge regulated by circRNAs, indicating the roles of circRNAs in regulating muscle growth-related genes expression. Overall, these findings will not only broaden our understanding of circRNAs regulation mechanisms underlying muscle growth and development in LMB but also provides a novel clue for further functional research in carnivorous fish genetic breeding.
环状RNA（circRNA）是一种新型的内源性调控非编码RNA分子，具有共价闭环结构，在多种生物学过程中发挥重要作用。已知circRNA作为功能性调节因子通过海绵作用与微小RNA（miRNA）相互作用来调节基因表达，据报道其可调节骨骼肌发育。然而，鱼类中参与调节肌肉生长和发育的circRNA信息在很大程度上尚不清楚。在此，我们首先分别利用RNA测序在幼年和成年大口黑鲈（LMB）的骨骼肌中鉴定出312个和511个circRNA。差异表达circRNA（DE-circRNA）分析表明，在两个不同的骨骼肌生长阶段有44个DE-circRNA。随机选择了6个circRNA，并通过实时PCR确认了它们在幼年和成年LMB中的相对表达水平，表明这些circRNA真实存在。此外，基因本体论（GO）注释和京都基因与基因组百科全书（KEGG）通路分析表明，这些DE-circRNA的宿主基因（其线性mRNA）主要富集于肌动蛋白细胞骨架信号通路的调节。circRNA-miRNA相互作用调控网络表明，一个circRNA可以调节一个或多个miRNA。例如，两个circRNA（circRNA389和circRNA399）调节了30多个miRNA。其中，发现包括let-7家族、miR-133和miR-26等在内的肌肉相关miRNA作为被circRNA调节的miRNA海绵，表明circRNA在调节肌肉生长相关基因表达中的作用。总体而言，这些发现不仅将拓宽我们对LMB肌肉生长和发育背后circRNA调控机制的理解，还为肉食性鱼类遗传育种的进一步功能研究提供了新线索。
