Circular RNA circMYL1 Inhibit Proliferation and Promote Differentiation of Myoblasts by Sponging miR-2400

Abstract

Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs (ncRNAs) involved in regulating skeletal muscle development by sponging miRNAs. In this study, we found that the circMYL1 expression was down-regulated during myoblast proliferation, while gradually up-regulated in myoblast differentiation. The potential role of circMYL1 was identified in the proliferation of bovine myoblast through mRNA and protein expression of proliferation marker genes (PCNA, CyclinD1, and CDK2), cell counting kit-8 assay, flow cytometry analysis, and 5-ethynyl 2′-deoxyuridine (EdU) assay. Analysis of the expression of differentiation marker genes (MyoD, MyoG, and MYH2) and immunofluorescence of Myosin heavy chain (MyHC) was used to assess cell differentiation. The proliferation analysis revealed that circMYL1 inhibited the proliferation of bovine primary myoblast. Furthermore, the differentiation analysis demonstrated that circMYL1 promoted the differentiation of bovine primary myoblast. The luciferase screening and RNA immunoprecipitation (RIP) assays found that circMYL1 could have interaction with miR-2400. Additionally, we demonstrated that miR-2400 promoted proliferation and inhibited differentiation of bovine primary myoblast, while circMYL1 may eliminate the effects of miR-2400, as showed by rescue experiments. Together, our results revealed that a novel circular RNA of circMYL1 could inhibit proliferation and promote differentiation of myoblast by sponging miR-2400.

Identification of CircRNA-Associated ceRNA Networks Using Longissimus Thoracis of Pigs of Different Breeds and Growth Stages

“…Our results showed that circKANSL1L decreased the expression level of PCNA, Cyclin D1, and Cyclin E in C 2 C 12 cells, eventually inhibiting their proliferation. Elnour et al also used PCNA and Cyclin D1 as marker genes to evaluate the state of cell proliferation, and they found that circMYL1 inhibited the proliferation of bovine primary myoblasts by sponging miR-2400 [55]. Our cell cycle analysis and CCK-8 assay results also indicated that circKANSL1L decreased the proliferation rate of C 2 C 12 cells.…”

Dynamic Expression and Regulatory Network of Circular RNA for Abdominal Preadipocytes Differentiation in Chicken (Gallus gallus)

“…With regard to livestock and poultry, some circRNAs have also been identified by high throughput sequencing and confirmed to participate in regulating their important biological process, such as embryos development ( Veno et al, 2015 ), formation of skeletal muscle fiber ( Li et al, 2020b ), hepatic lipid metabolism ( Huang et al, 2018 ), and adipogenic differentiation ( Li A. et al, 2018 ) in pig; muscle growth and development ( Wei et al, 2017 ; Li et al, 2018b ; Li et al, 2018c ; Liu et al, 2020 ; Shen et al, 2020 ; Yue et al, 2020 ; Elnour et al, 2021 ), testis development ( Gao et al, 2018 ), adipogenesis ( Jiang et al, 2020 ) and milk fat content ( Chen et al, 2021 ) in cattle; fat deposition in buffalo and yak ( Huang et al, 2019 ; Wang H. et al, 2020 ); intramuscular fat (IMF) content denoting a crucial indicator of meat quality in donkey ( Li et al, 2020a ); follicular development ( Shen et al, 2019 ), Marek’s tumourigenesis ( Wang L. et al, 2020 ) as well as muscle growth development ( Ouyang et al, 2018a ; Ouyang et al, 2018b ) in chicken. And it has yet indicated some functional circRNAs related to lipid metabolism, for instance, circFUT10 could promote bovine preadipocyte proliferation but inhibit adipocyte differentiation ( Jiang et al, 2020 ); circRNA_26852 and circRNA_11897, might get involved in porcine adipocyte differentiation and lipid metabolism ( Li A. et al, 2018 ); circ11103 could increase the triglyceride levels in bovine mammary epithelial cells and the contents of unsaturated fatty acids ( Chen et al, 2021 ); additionally, 19:45387150|45389986 and 21:6969877|69753491, were deemed as potential modulators of buffalo back subcutaneous adipose deposition ( Huang et al, 2019 ).…”

Identification of circRNA-associated ceRNA networks using longissimus thoracis of pigs of different breeds and growth stages

“…found that circFUT10 inhibited myoblast proliferation by blocking cells in the G1/G0 phase [ 45 ]. Myf5, MyoD1, and MyoG, as core myogenic regulators, play a key role in myogenesis [ 54 , 55 ]. The transcription factor MYOG is involved in the regulation of myocyte fusion and is essential for the growth of muscle fibers and proliferation of muscle nuclei [ 56 ].…”