College of Animal Science, Shanxi Agricultural University, Taigu, Jinzhong 030801, China.
Int J Mol Sci. 2023 Feb 14;24(4):3779. doi: 10.3390/ijms24043779.
Muscle development is closely related to meat quality and production. CircRNAs, with a closed-ring structure, have been identified as a key regulator of muscle development. However, the roles and mechanisms of circRNAs in myogenesis are largely unknown. Hence, in order to unravel the functions of circRNAs in myogenesis, the present study explored circRNA profiling in skeletal muscle between Mashen and Large White pigs. The results showed that a total of 362 circRNAs, which included circIGF1R, were differentially expressed between the two pig breeds. Functional assays showed that circIGF1R promoted myoblast differentiation of porcine skeletal muscle satellite cells (SMSCs), while it had no effect on cell proliferation. In consideration of circRNA acting as a miRNA sponge, dual-luciferase reporter and RIP assays were performed and the results showed that circIGF1R could bind miR-16. Furthermore, the rescue experiments showed that circIGF1R could counteract the inhibitory effect of miR-16 on cell myoblast differentiation. Thus, circIGF1R may regulate myogenesis by acting as a miR-16 sponge. In conclusion, this study successfully screened candidate circRNAs involved in the regulation of porcine myogenesis and demonstrated that circIGF1R promotes myoblast differentiation via miR-16, which lays a theoretical foundation for understanding the role and mechanism of circRNAs in regulating porcine myoblast differentiation.
肌肉发育与肉质和产量密切相关。circRNAs 具有闭环结构，被认为是肌肉发育的关键调节因子。然而，circRNAs 在成肌中的作用和机制在很大程度上尚不清楚。因此，为了阐明 circRNAs 在成肌中的功能，本研究在马身猪和大白猪的骨骼肌之间探索了 circRNA 图谱。结果表明，在这两个猪品种之间，共有 362 个 circRNAs（包括 circIGF1R）存在差异表达。功能分析表明，circIGF1R 促进了猪骨骼肌卫星细胞（SMSCs）的成肌分化，而对细胞增殖没有影响。考虑到 circRNA 作为 miRNA 海绵的作用，进行了双荧光素酶报告和 RIP 测定，结果表明 circIGF1R 可以与 miR-16 结合。此外，挽救实验表明，circIGF1R 可以抵消 miR-16 对细胞成肌分化的抑制作用。因此，circIGF1R 可能通过充当 miR-16 海绵来调节成肌作用。总之，本研究成功筛选出参与调控猪成肌的候选 circRNAs，并证明 circIGF1R 通过 miR-16 促进成肌分化，为理解 circRNAs 在调控猪成肌分化中的作用和机制奠定了理论基础。
