Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Int J Mol Sci. 2023 Jul 17;24(14):11567. doi: 10.3390/ijms241411567.
Reducing fat deposition in sheep () tails is one of the most important ways to combat rising costs and control consumer preference. Our previous studies have shown that oar-miR-432 is differentially expressed in the tail adipose tissue of Hu (a fat-tailed sheep breed) and Tibetan (a thin-tailed sheep breed) sheep and is a key factor in the negative regulation of fat deposition through in ovine preadipocytes. This study investigated the effect of oar-miR-432 and its target genes in ovine preadipocytes. A dual luciferase assay revealed that is a direct target gene of oar-miR-432. We transfected an oar-miR-432 mimic and inhibitor into preadipocytes to analyze the expression of target genes. Overexpression of oar-miR-432 inhibits expression, whereas inhibition showed the opposite results. Compared with thin-tailed sheep, was highly expressed in the fat-tailed sheep at the mRNA and protein levels. Furthermore, we transfected the overexpression and knockdown target genes into preadipocytes to analyze their influence after inducing differentiation. Knockdown of induced ovine preadipocyte differentiation into adipocytes but suppressed oar-miR-432 expression. Conversely, the overexpression of significantly inhibited differentiation but promoted oar-miR-432 expression. overexpression also decreased the content of triglycerides. Additionally, is a nested gene in intron 1 of . When was overexpressed, the expression also increased, whereas knockdown showed the opposite results. This is the first study to reveal the biological mechanisms by which oar-miR-432 inhibits preadipocytes through and provides insight into the molecular regulatory mechanisms of in ovine preadipocytes. These results have important applications in animal breeding and obesity-related human diseases.
减少绵羊尾巴脂肪沉积是应对成本上升和控制消费者偏好的最重要方法之一。我们之前的研究表明，oar-miR-432 在 Hu（一种脂肪尾巴绵羊品种）和西藏（一种瘦尾巴绵羊品种）绵羊的尾巴脂肪组织中差异表达，是通过在绵羊前体脂肪细胞中负调控脂肪沉积的关键因素。本研究探讨了 oar-miR-432 及其靶基因在绵羊前体脂肪细胞中的作用。双荧光素酶报告基因实验表明，是 oar-miR-432 的直接靶基因。我们将 oar-miR-432 模拟物和抑制剂转染到前体脂肪细胞中，分析靶基因的表达。oar-miR-432 的过表达抑制了的表达，而抑制则显示出相反的结果。与瘦尾绵羊相比，在脂肪尾绵羊中，在 mRNA 和蛋白水平上均高度表达。此外，我们将过表达和敲低靶基因转染到前体脂肪细胞中，分析诱导分化后的影响。敲低抑制了绵羊前体脂肪细胞向脂肪细胞的分化，但促进了 oar-miR-432 的表达。相反，的过表达显著抑制了分化，但促进了 oar-miR-432 的表达。的过表达还降低了甘油三酯的含量。此外，是基因的内含子 1 中的嵌套基因。当过表达时，的表达也增加，而敲低则显示出相反的结果。这是首次揭示 oar-miR-432 通过抑制前体脂肪细胞的生物学机制，为研究在绵羊前体脂肪细胞中的分子调控机制提供了新视角。这些结果在动物育种和肥胖相关人类疾病的研究中具有重要应用价值。
