Laboratory of Animal Biotechnology and Breeding, College of Animal Science and Veterinary Medicine, Xinyang College of Agriculture and Forestry, Xinyang, Henan, China.
College of Life Science, Xinyang Normal University, Xinyang, Henan, China.
Anim Sci J. 2019 Sep;90(9):1278-1286. doi: 10.1111/asj.13264. Epub 2019 Jul 10.
Intramuscular fat (IMF) content has been identified as a crucial factor of porcine meat quality. MAT2A and MAT2B coordinately catalyzes the synthesis of the major biological methyl donor S-adenosylmethionine (SAMe). However, the regulatory effect of MAT2A and MAT2B on porcine intramuscular preadipocyte proliferation has not been clarified. In this study, we investigated the effect of MAT2A and MAT2B and its potential mechanism during porcine intramuscular proliferation. We demonstrated that overexpression of MAT2A and MAT2B promoted the cell cycle progression of porcine preadipocyte by flow cytometry and EdU-labeling assay, as well as promoted the expression of cell cycle marker genes including Cyclin B, Cyclin D, and Cyclin-dependent kinase 4, but reduced the expression of cell cycle inhibitor P27. Consistently, knockdown of MAT2A and MAT2B inhibited cell cycle progression and downregulated the mRNA and protein levels of the above genes. Furthermore, overexpression of MAT2A and MAT2B activated the phosphorylation of ERK1/2. Moreover, the inhibitory effect of U0126 (a specific ERK1/2 inhibitor) on the ERK1/2 activities was partially recovered by overexpression of MAT2A and MAT2B in porcine intramuscular preadipocytes. Taken together, our findings suggested that MAT2A and MAT2B promote porcine preadipocyte proliferation by ERK1/2 signaling pathway.
肌肉内脂肪（IMF）含量已被确定为猪肉质的关键因素。MAT2A 和 MAT2B 协同催化主要生物甲基供体 S-腺苷甲硫氨酸（SAMe）的合成。然而，MAT2A 和 MAT2B 对猪肌肉前体脂肪细胞增殖的调节作用尚未阐明。在本研究中，我们研究了 MAT2A 和 MAT2B 的作用及其在猪肌肉增殖过程中的潜在机制。我们通过流式细胞术和 EdU 标记实验证明，MAT2A 和 MAT2B 的过表达促进了猪前体脂肪细胞的细胞周期进程，以及细胞周期标记基因包括 Cyclin B、Cyclin D 和 Cyclin-dependent kinase 4 的表达，但降低了细胞周期抑制剂 P27 的表达。一致地，MAT2A 和 MAT2B 的敲低抑制了细胞周期进程，并下调了上述基因的 mRNA 和蛋白水平。此外，MAT2A 和 MAT2B 的过表达激活了 ERK1/2 的磷酸化。此外，在猪肌肉前体脂肪细胞中，过表达 MAT2A 和 MAT2B 部分恢复了 U0126（一种特定的 ERK1/2 抑制剂）对 ERK1/2 活性的抑制作用。综上所述，我们的研究结果表明，MAT2A 和 MAT2B 通过 ERK1/2 信号通路促进猪前体脂肪细胞增殖。
