RESUMEN
N6-methyladenosine (m6A) plays a crucial role in many bioprocesses across species, but its function in granulosa cells during oocyte maturation is not well understood in animals, especially domestic animals. We observed an increase in m6A methyltransferase-like 3 (METTL3) in granulosa cells during oocyte maturation in Haimen goats. Our results showed that knockdown of METTL3 disrupted the cell cycle in goat granulosa cells, leading to aggravated cell apoptosis and inhibition of cell proliferation and hormone secretion. Mechanistically, METTL3 may regulate the cell cycle in goat granulosa cells by mediating Aurora kinase B (AURKB) mRNA degradation in an m6A-YTH N6-methyladenosine RNA binding protein 2 (YTHDF2) manner and participating in AURKB transcription via the Cyclin D1 (CCND1)-Retinoblastoma protein (RB)-E2F transcription factor 1 (E2F1) pathway. Overall, our study highlights the essential role of METTL3 in granulosa cells during oocyte maturation in Haimen goats. These findings provide a theoretical basis and technical means for understanding how RNA methylation participates in oocyte maturation through granulosa cells.
Asunto(s)
Cabras , Metiltransferasas , Animales , Femenino , Metiltransferasas/genética , Metiltransferasas/metabolismo , Cabras/metabolismo , Aurora Quinasa B , Ciclina D1/genética , Ciclo CelularRESUMEN
Neuromedin S (NMS) is a neuroregulatory substance and has many important roles in regulating physiological functions in animal cells, while their specific functions and mechanisms in Leydig cells (LCs) of the testis remain unclear. The current study aims to investigate the role and potential mechanisms of NMS and its receptors in regulating steroidogenesis and proliferation in goat LCs. We found that NMS and its receptors were mainly expressed in LCs of goat testes at different ages (1-day-old, 3-month-old, and 9-month-old), and the highest expressions detected at age three months. NMS addition significantly enhanced the testosterone secretion, STAR, CYP11A1, 3BHSD, and CYP17A1 expressions, cell proliferation, and PCNA expression in vitro cultured goat LCs. Mechanistically, NMS addition increased G1/S cell population, the expressions of CCND1, CDK4 and CDK6, the activities of SOD2 and CAT, and enhanced the mitochondrial fusion, the production of ATP, and mitochondrial membrane potential, while inhibited cellular ROS production, and maintained a low ubiquitination level of mitochondrial proteins. Notably, these effects of NMS addition on goat LCs were suppressed by co-treatment with NMUR2 knockdown. Therefore, these data suggest that activating NMUR2 with NMS enhances testosterone production and cell proliferation in goat LCs through modulating mitochondrial morphology, function, and autophagy. These findings may provide a novel view of the regulatory mechanisms involved in male sexual maturation.
Asunto(s)
Cabras , Células Intersticiales del Testículo , Animales , Masculino , Células Intersticiales del Testículo/metabolismo , Cabras/metabolismo , Testosterona/metabolismo , Mitocondrias/metabolismo , Proliferación CelularRESUMEN
Recent evidence suggested that N6-methyladenosine (m6A) methylation can determine m6A-modified mRNA fate and play an important role in skeletal muscle development. It was well known that transforming growth factor beta 1 (TGFß1) is involved in a variety of cellular processes, such as proliferation, differentiation, and apoptosis. However, little is known about the m6A-mediated TGFß1 regulation in myogenesis. Here, we observed an increase in endogenous TGFß1 expression and activity during myotube differentiation. However, the knockdown of TGFß1 inhibits the proliferation and induces cell apoptosis of myoblast. Moreover, we found that m6A in 5'-untranslated regions (5'UTR) of TGFß1 promote its decay and inhibit its expression, leading to the blockage of the TGFß1/SMAD2 signaling pathway. Furthermore, the targeted specific demethylation of TGFß1 m6A using dCas13b-FTO significantly increased the TGFß1-mediated activity of the SMAD2 signaling pathway, promoting myoblast proliferation. These findings suggest that TGFß1 is an essential regulator of myoblast growth that is negatively regulated by m6A. Overall, these results highlight the critical role of m6A-mediated post-transcriptional regulation in myogenesis.