基于细胞凋亡与程序性坏死探讨miR-365-3p/SelT轴在缺硒性鸡成肌细胞增殖分化障碍中的作用

硒主要通过硒蛋白发挥生物学功能，前期研究发现，miR-365-3p靶向调控SelT，缺硒可引起骨骼肌细胞凋亡、程序性坏死和成肌细胞稳态紊乱，但miR-365-3p/SelT轴在成肌细胞增殖分化中的作用尚不清楚。本课题构建鸡缺硒病、成肌细胞和鸡胚miR-365-3p/SelT敲低/过表达模型，应用透射电镜、RT-PCR、免疫印迹、流式细胞术等方法，检测骨骼肌形态、成肌细胞稳态（MyoD、MYF-5、MHC等）、氧化应激（ROS、MDA、GPx等）、钙稳态调控蛋白（STIM1、TRPC1等）、线粒体动力学（Mfn1/2、OPA1、Drp1等）、细胞凋亡与程序性坏死（bcl-2、caspase-3、cyt-c、RIPK1/3、MLKL等）及相关信号通路等，旨在阐明缺硒通过miR-365-3p/SelT轴诱导细胞凋亡和程序性坏死调控鸡成肌细胞增殖分化障碍的机理，为拓展硒生物学功能提供依据。

Selenium works through selenoproteins for exerting the biological function. Previous study found that miR-365-3p not only caused apoptosis, necroptosis and autophagy of skeletal muscle cells, but also disordered myoblasts in selenium deficiency induced skeletal muscle injury by targeting to selenium protein T (SelT). However, the role of miR-365-3p/SelT axis in myoblasts proliferation and differentiation remains unclear. On the basis of the chicken selenium deficiency induced skeletal muscle injury model, and miR-365-3p or SelT knockdown/overexpression chicken myoblast or chicken embryo model, we the observed the skeletal muscle morphological changes, measured myoblast homeostasis pathways related genes (MyoD, MYF-5 and MHC, etc), oxidative stress indicators (ROS, MDA, GPx, etc.), calcium homeostasis related proteins (STIM1 and TRPC1, etc.), mitochondrial dynamics related genes (Mfn1/2 OPA1, Drp1), cell apoptosis and necroptosis related pathways (bcl-2, caspase-3, cyt-c, RIPK1/3 and MLKL, etc.) and other pathways by using transmission electron microscopy, RT-PCR, Western blot, and flow cytometry methods. This study aims to elucidate the mechanism of selenium deficiency inducedmyoblast proliferation and differentiation disorder by regulating cell apoptosis and necroptosis programmed necrosis via miR-365-3p/SelT axis, which also provide a basis for expanding the biological function of selenium.