Androgen receptor expression during C2C12 skeletal muscle cell line differentiation.
The Androgen Receptor (AR) pathway is involved in the development of skeletal muscle but the molecular basis of androgen-related myogenic enhancement is still unclear. We have investigated AR expression and localization during myoblasts-myotubes differentiation in skeletal muscle cell line C2C12. AR expression increases during proliferation and commitment phase and its levels remain elevated in myotubes. In proliferating and committed cells in the absence of testosterone, AR protein localizes in the nuclei whereas it is almost totally localized in the cytoplasm in myotubes. Low testosterone doses shift the receptor in the nuclei without increasing the amount of total protein. High doses of T induce a significant increase of AR expression during proliferation and differentiation. Little information is available on AR targets that drive the myogenic process. In our study, testosterone induces myogenin, myosin heavy chains (MyHC) and GRIP-1 expression, suggesting that AR and its coregulatory proteins are pivotal factors in skeletal muscle differentiation.
Wannenes
Francesca
F
Department of Sciences of Human Movement and Sport, IUSM-University of Sport and Movement Sciences, Rome, Italy.
Caprio
Massimiliano
M
Gatta
Lucia
L
Fabbri
Andrea
A
Bonini
Sergio
S
Moretti
Costanzo
C
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects; D051379:Mice; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000166:cytology*; D018008:Myogenin / Q000235:genetics / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism*; D015203:Reproducibility of Results; D013739:Testosterone / Q000494:pharmacology; D013997:Time Factors
D048868:Adaptor Proteins, Signal Transducing; C491309:Grip1 protein, mouse; D018008:Myogenin; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D011944:Receptors, Androgen; D013739:Testosterone; D018995:Myosin Heavy Chains