MEG3 Promotes Differentiation of Porcine Satellite Cells by Sponging miR-423-5p to Relieve Inhibiting Effect on SRF

Abstract

Although thousands of long noncoding RNAs (lncRNAs) have been identified in porcine growth and development, the regulation mechanisms of functional lncRNAs have not been well explored. In this study, using 5′- and 3′-rapid amplification of cDNA ends (RACE) assays, we obtained two different variants of lncRNA maternally expressed gene 3 (MEG3), namely, MEG3 v1 and MEG3 v2, that were both highly expressed in porcine skeletal muscle and in the early stage of the differentiation of porcine satellite cells. Moreover, we identified the core transcript MEG3 v2. Functional analyses showed that MEG3 overexpression could effectively arrest myoblasts in the G1 phase, inhibit DNA replication, and promote myoblast differentiation, whereas MEG3 knockdown resulted in the opposite effects. Interestingly, the expression of serum response factor (SRF), a crucial transcription factor for myogenesis process, remarkably increased and decreased in mRNA and protein levels with the respective overexpression and knockdown of MEG3. Dual luciferase reporter assay showed that MEG3 could attenuate the decrease of luciferase activity of SRF induced by miR-423-5p in a dose-dependent manner. MEG3 overexpression could relieve the inhibitory effect on SRF and myoblast differentiation induced by miR-423-5p. In addition, results of RNA immunoprecipitation analysis suggested that MEG3 could act as a ceRNA for miR-423-5p. Our findings initially established a novel connection among MEG3, miR-423-5p, and SRF in porcine satellite cell differentiation. This novel role of MEG3 may shed new light on understanding of molecular regulation of lncRNA in porcine myogenesis.

CircMEG3 inhibits telomerase activity by reducing Cbf5 in human liver cancer stem cells

“…39 MEG3 activated by vitamin D suppresses glycolysis in cancer, 40 and MEG3 induces invasion of glioma cells via autophagy. 41 Moreover, MEG3 promotes differentiation of porcine satellite cells by sponging miR-423-5p 42 and is involved in pituitary tumor invasiveness. 43 In addition, MEG3 inhibits the inflammatory response of ankylosing spondylitis, 44 and MEG3 inhibits HMEC-1 cell growth and migration.…”

Integrated Analysis Reveals a lncRNA–miRNA–mRNA Network Associated with Pigeon Skeletal Muscle Development

“…Genetic factors such as transcription factors, gene polymorphism, DNA methylation, and non-coding RNAs (ncRNAs) work together to control skeletal muscle development [45,46]. Recent studies have confirmed the essential roles of lncRNA in regulating skeletal muscle development [23][24][25]. However, the expression of lncRNAs in pigeon skeletal muscle remains unknown.…”

“…An increasing number of research aiming to construct lncRNA-associated ceRNA networks in myogenesis has been conducted [20,48,49]. The involvement of lncRNA as ceRNA in regulating animal skeletal muscle development has also been described [23][24][25]50,51].Therefore, constructing a ceRNA network may help elucidate the regulatory mechanisms underlying the development of pigeon skeletal muscle. In this study, we first identified 1625 DE lncRNAs, 573 DE miRNAs, and 11,311 DE mRNAs between muscle samples of different developmental ages.…”

“…According to the ceRNA hypothesis, many investigators have devoted themselves to elucidating the ceRNA roles of lncRNAs in skeletal muscle myogenesis by constructing ceRNA networks [19][20][21][22]. Studies have shown that lncRNA can regulate skeletal muscle myogenesis of poultry and livestock by acting as ceRNA [23][24][25]. However, the regulatory mechanisms of lncRNA as ceRNA, and the lncRNA-associated ceRNA network involved in skeletal muscle development of pigeons remain elusive.…”

Regulation of Skeletal Muscle Atrophy in Cachexia by MicroRNAs and Long Non-coding RNAs

“…In summary, there have been significant advances in our understanding of the crucial roles of miRNAs and lncRNAs in regulating skeletal muscle development (Cesana et al, 2011;Legnini et al, 2014;Zhu et al, 2017;Kong et al, 2019;Cheng et al, 2020;Li et al, 2020). A limited number of studies have specifically identified roles of miRNAs and lncRNAs in muscular atrophy in cachexia and other diseases, and these studies suggest that miRNAs and lncRNAs are central to abnormal regulation of protein synthesis and degradation.…”