小鼠骨骼肌干细胞蛋白标志JAK的发现

目的通过骨骼肌卫星细胞的体外培养,探讨骨骼肌干细胞蛋白表达标志Pax7,发现新的与骨骼肌干细胞的生长、分化密切相关的表达蛋白。方法采用两种小鼠骨骼肌干细胞分离、纯化及培养方法,一种是采取成年小鼠的趾短屈肌(FDB)分离切割后,体外培养出单个骨骼肌干细胞;另一种是取成年小鼠FDB,分离出单个肌纤维丝(fiber)并体外培养。应用免疫荧光染色法对骨骼肌干细胞进行鉴定。运用RNAi技术将JAK1蛋白敲除。结果发现Pax7表达阳性的细胞质内有JAK1蛋白表达,并运用RNAi技术将JAK1蛋白敲除,结果显示骨骼肌干细胞迅速分化。结论 FDB肌纤维的体外培养是一个良好的体内肌肉状态的模型,同时发现了一种新的与骨骼肌增殖分化有关的骨骼肌干细胞蛋白标志JAK1。

JAK1:a novel protein marker in mice skeletal muscle stem cell

Objective Through culturing in vitro skeletal muscle satellite cells to explore muscle stem cell protein expression marker Pax7,and discover a new protein expression marker which is closely related to the growth and differentiation of the skeletal muscle stem cells.Methods Two methods of isolation and culture of satellite cells were established.In one model,the single satellite cell was disassociated after isolation of mice flexor digitorum brevis(FDB) muscle to culture in vitro.In the other one,single fiber was isolated from the same tissue of the mice,then was cultured in vitro.The satellite cells were identified by immunodetection.Results Pax7+ satellite cells also expressed JAK1 in the cytoplasm.The satellite cells differentiated rapidly after knockdown of JAK1 of satellite cells by RNA interference.Conclusions FDB myofiber cultures in vitro is an excellent model of microcosm state of muscle.Furthermore,a new protein marker JAK1 is found,which is closely related to the differentiation of skeletal muscle stem cells.