Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization Key Laboratory of Sichuan Province, Southwest Minzu University, Chengdu 610041, China.
Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Southwest Minzu University, Ministry of Education, Chengdu 610041, China.
Cells. 2024 Aug 30;13(17):1459. doi: 10.3390/cells13171459.
Meat quality in goats is partly determined by the intramuscular fat (IMF) content, which is associated with the proliferation and differentiation of intramuscular preadipocytes. Emerging studies have suggested that miRNA plays a crucial role in adipocyte proliferation and differentiation. In our recent study, we observed the expression variations in miR-196a in the longissimus dorsi muscle of Jianzhou goats at different ages. However, the specific function and underlying mechanism of miR-196a in IMF deposition are still unclear. This study demonstrated that miR-196a significantly enhanced adipogenesis and apoptosis and reduced the proliferation of preadipocytes. Subsequently, RNA-seq was employed to determine genes regulated by miR-196a, and 677 differentially expressed genes were detected after miR-196a overexpression. The PI3K-Akt pathway was identified as activated in miR-196a regulating intramuscular adipogenesis via Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and further verified via Western blot and rescue assays. Lastly, using RT-qPCR, Western blot, dual-luciferase, and rescue assays, we found that miR-196a promoted adipogenesis and suppressed the proliferation of intramuscular preadipocytes by the downregulation of . In summary, these results suggest that miR-196a regulates IMF deposition by targeting and activating the PI3K-Akt pathway and provide a theoretical foundation for improving goat meat quality through molecular breeding.
山羊的肉质部分取决于肌内脂肪（IMF）含量，这与肌内前体脂肪细胞的增殖和分化有关。新的研究表明，miRNA 在脂肪细胞增殖和分化中起着关键作用。在我们最近的研究中，我们观察到不同年龄间马里努阿犬背最长肌中 miR-196a 的表达变化。然而，miR-196a 在 IMF 沉积中的具体功能和潜在机制尚不清楚。本研究表明，miR-196a 显著增强了脂肪生成和凋亡，减少了前体脂肪细胞的增殖。随后，通过 RNA-seq 确定了受 miR-196a 调控的基因，在过表达 miR-196a 后检测到 677 个差异表达基因。通过京都基因与基因组百科全书（KEGG）分析，发现 PI3K-Akt 通路在 miR-196a 调节肌内脂肪生成中被激活，并通过 Western blot 和挽救实验进一步验证。最后，通过 RT-qPCR、Western blot、双荧光素酶报告基因和挽救实验，我们发现 miR-196a 通过下调 来促进脂肪生成和抑制肌内前体脂肪细胞的增殖。总之，这些结果表明，miR-196a 通过靶向 并激活 PI3K-Akt 通路来调节 IMF 沉积，为通过分子育种提高羊肉质量提供了理论基础。
