通过随机插入和 CRISPR/Cas9 转基因猪克隆技术在骨骼肌中靶向过表达 PPARγ 可增强氧化纤维的形成和肌内脂肪的沉积。
Targeted overexpression of PPARγ in skeletal muscle by random insertion and CRISPR/Cas9 transgenic pig cloning enhances oxidative fiber formation and intramuscular fat deposition.
机构信息
Key Laboratory of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs & Key Laboratory of Agriculture Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, P.R. China.
Department of Human Nutrition, Food and Animal Sciences, University of Hawaii at Manoa, Honolulu, HI, USA.
出版信息
FASEB J. 2021 Feb;35(2):e21308. doi: 10.1096/fj.202001812RR.
Peroxisome proliferator-activated receptor gamma (PPARγ) is a master regulator of adipogenesis and lipogenesis. To understand its roles in fiber formation and fat deposition in skeletal muscle, we successfully generated muscle-specific overexpression of PPARγ in two pig models by random insertion and CRISPR/Cas9 transgenic cloning procedures. The content of intramuscular fat was significantly increased in PPARγ pigs while had no changes on lean meat ratio. PPARγ could promote adipocyte differentiation by activating adipocyte differentiating regulators such as FABP4 and CCAAT/enhancer-binding protein (C/EBP), along with enhanced expression of LPL, FABP4, and PLIN1 to proceed fat deposition. Proteomics analyses demonstrated that oxidative metabolism of fatty acids and respiratory chain were activated in PPARγ pigs, thus, gathered more Ca in PPARγ pigs. Raising of Ca could result in increased phosphorylation of CAMKII and p38 MAPK in PPARγ pigs, which can stimulate MEF2 and PGC1α to affect fiber type and oxidative capacity. These results support that skeletal muscle-specific overexpression of PPARγ can promote oxidative fiber formation and intramuscular fat deposition in pigs.
过氧化物酶体增殖物激活受体 γ(PPARγ)是脂肪生成和脂生成的主要调节因子。为了了解其在骨骼肌纤维形成和脂肪沉积中的作用,我们通过随机插入和 CRISPR/Cas9 转基因克隆程序成功地在两种猪模型中肌肉特异性过表达了 PPARγ。PPARγ 猪的肌内脂肪含量显著增加,而瘦肉率没有变化。PPARγ 可以通过激活脂肪细胞分化调节因子(如 FABP4 和 CCAAT/增强子结合蛋白(C/EBP))促进脂肪细胞分化,并增强 LPL、FABP4 和 PLIN1 的表达,从而进行脂肪沉积。蛋白质组学分析表明,PPARγ 猪的脂肪酸氧化代谢和呼吸链被激活,因此在 PPARγ 猪中积聚了更多的 Ca。Ca 的增加会导致 PPARγ 猪中 CAMKII 和 p38 MAPK 的磷酸化增加,这可以刺激 MEF2 和 PGC1α 影响纤维类型和氧化能力。这些结果支持在猪中肌肉特异性过表达 PPARγ 可以促进氧化纤维形成和肌内脂肪沉积。