Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Xianyang 712100, China.
Int J Mol Sci. 2022 Mar 26;23(7):3640. doi: 10.3390/ijms23073640.
MicroRNA (miRNA)-130b, as a regulator of lipid metabolism in adipose and mammary gland tissues, is actively involved in lipogenesis, but its endogenous role in fatty acid synthesis remains unclear. Here, we aimed to explore the function and underlying mechanism of miR-130b in fatty acid synthesis using the CRISPR/Cas9 system in primary goat mammary epithelial cells (GMEC). A single clone with deletion of 43 nucleotides showed a significant decrease in miR-130b-5p and miR-130b-3p abundances and an increase of target genes and . In addition, knockout of miR-130b promoted triacylglycerol (TAG) and cholesterol accumulation, and decreased the proportion of monounsaturated fatty acids (MUFA) C16:1, C18:1 and polyunsaturated fatty acids (PUFA) C18:2, C20:3, C20:4, C20:5, C22:6. Similarly, the abundance of fatty acid synthesis genes and and transcription regulators SREBP1c and SREBP2 was elevated. Subsequently, interference with instead of in knockout cells restored the effect of miR-130b knockout, suggesting that is responsible for miR-130b regulating fatty acid synthesis. Moreover, disrupting inhibits transcription and translation. These results reveal that miR-130b directly targets the PPARG-PGC1α axis, to inhibit fatty acid synthesis in GMEC. In conclusion, miR-130b could be a potential molecular regulator for improving the beneficial fatty acids content in goat milk.
微小 RNA（miRNA）-130b 作为脂肪组织和乳腺组织中脂质代谢的调节剂，积极参与脂肪生成，但它在脂肪酸合成中的内源性作用尚不清楚。在这里，我们使用原代山羊乳腺上皮细胞（GMEC）中的 CRISPR/Cas9 系统，旨在探索 miR-130b 在脂肪酸合成中的功能和潜在机制。一个缺失 43 个核苷酸的单克隆显示 miR-130b-5p 和 miR-130b-3p 的丰度显著降低，靶基因 和 的丰度增加。此外，miR-130b 的敲除促进了三酰基甘油（TAG）和胆固醇的积累，并降低了单不饱和脂肪酸（MUFA）C16:1、C18:1 和多不饱和脂肪酸（PUFA）C18:2、C20:3、C20:4、C20:5、C22:6 的比例。同样，脂肪酸合成基因 和 以及转录调节剂 SREBP1c 和 SREBP2 的丰度升高。随后，干扰 而不是 中的敲除细胞恢复了 miR-130b 敲除的效果，表明 是 miR-130b 调节脂肪酸合成的原因。此外，破坏 抑制 转录和翻译。这些结果表明，miR-130b 直接靶向 PPARG-PGC1α 轴，抑制 GMEC 中的脂肪酸合成。总之，miR-130b 可以作为一种潜在的分子调节剂，用于提高羊奶中有益脂肪酸的含量。
