title: Androgen receptor regulates expression of skeletal muscle-specific proteins and muscle cell types.
abstract: 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.
authors.affiliation: George Whipple Lab for Cancer Research, Department of Pathology, The Cancer Center, University of Rochester Medical Center, Rochester, New York 14642, USA.
authors.forename: Saleh
authors.initials: S
authors.lastname: Altuwaijri
authors.forename: Dong Kun
authors.initials: DK
authors.lastname: Lee
authors.forename: Kuang-Hsiang
authors.initials: KH
authors.lastname: Chuang
authors.forename: Huei-Ju
authors.initials: HJ
authors.lastname: Ting
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Yang
authors.forename: Qingquan
authors.initials: Q
authors.lastname: Xu
authors.forename: Meng-Yin
authors.initials: MY
authors.lastname: Tsai
authors.forename: Shuyuan
authors.initials: S
authors.lastname: Yeh
authors.forename: LeRoy A
authors.initials: LA
authors.lastname: Hanchett
authors.forename: Hong-Chiang
authors.initials: HC
authors.lastname: Chang
authors.forename: Chawnshang
authors.initials: C
authors.lastname: Chang
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D015536:Down-Regulation; D006614:Hindlimb; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D018345:Mice, Knockout; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000378:metabolism; D018657:Muscle Fibers, Slow-Twitch / Q000378:metabolism; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000166:cytology* / Q000378:metabolism*; D032446:Myoblasts / Q000166:cytology*; D011944:Receptors, Androgen / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D015854:Up-Regulation
chemical_list: D009124:Muscle Proteins; D011944:Receptors, Androgen