Altuwaijri Saleh, Lee Dong Kun, Chuang Kuang-Hsiang, Ting Huei-Ju, Yang Zhiming, Xu Qingquan, Tsai Meng-Yin, Yeh Shuyuan, Hanchett LeRoy A, Chang Hong-Chiang, Chang Chawnshang
George Whipple Lab for Cancer Research, Department of Pathology, The Cancer Center, University of Rochester Medical Center, Rochester, New York 14642, USA.
Endocrine. 2004 Oct;25(1):27-32. doi: 10.1385/endo:25:1:27.
C2C12 myoblasts expressing the androgen receptor (AR) were used to analyze the role of androgen-AR signaling pathway in skeletal muscle development. Marked up-regulation of AR expression was observed in differentiated myotubes. A nuclear run-on transcription assay demonstrated that transcription of the AR gene is increased during skeletal muscle cell differentiation. Regulation of skeletal muscle-specific protein expression by the androgen-AR signaling pathway was further analyzed using quadriceps skeletal muscle from wild-type (WT) and AR knock-out (ARKO) male mice. A histological analysis of quadriceps skeletal muscle indicates no morphological differences between ARKO and WT mice. However, the androgen-AR signaling pathway increases expression of slow-twitch-specific skeletal muscle proteins and downregulates fast-twitch-specific skeletal muscle proteins, resulting in an increase of slow-twitch muscle fiber type cells in quadriceps muscle.
利用表达雄激素受体（AR）的C2C12成肌细胞来分析雄激素-AR信号通路在骨骼肌发育中的作用。在分化的肌管中观察到AR表达显著上调。一项核转录分析表明，AR基因的转录在骨骼肌细胞分化过程中增加。使用野生型（WT）和AR基因敲除（ARKO）雄性小鼠的股四头肌进一步分析雄激素-AR信号通路对骨骼肌特异性蛋白表达的调节。股四头肌的组织学分析表明，ARKO小鼠和WT小鼠之间没有形态学差异。然而，雄激素-AR信号通路增加了慢肌纤维特异性骨骼肌蛋白的表达，并下调了快肌纤维特异性骨骼肌蛋白的表达，导致股四头肌中慢肌纤维类型细胞增加。
