| First Author | Fu X | Year | 2013 |
| Journal | Mol Cell Biol | Volume | 33 |
| Issue | 22 | Pages | 4517-25 |
| PubMed ID | 24043309 | Mgi Jnum | J:206092 |
| Mgi Id | MGI:5547880 | Doi | 10.1128/MCB.01078-13 |
| Citation | Fu X, et al. (2013) AMP-activated protein kinase alpha1 but not alpha2 catalytic subunit potentiates myogenin expression and myogenesis. Mol Cell Biol 33(22):4517-25 |
| abstractText | The link between AMP-activated protein kinase (AMPK) and myogenesis remains poorly defined. AMPK has two catalytic alpha subunits, alpha1 and alpha2. We postulated that AMPK promotes myogenesis in an isoform-specific manner. Primary myoblasts were prepared from AMPK knockout (KO) mice and AMPK conditional KO mice, and knockout of the alpha1 but not the alpha2 subunit resulted in downregulation of myogenin and reduced myogenesis. Myogenin expression and myogenesis were nearly abolished in the absence of both AMPKalpha1 and AMPKalpha2, while enhanced AMPK activity promoted myogenesis and myotube formation. The AMPKalpha1-specific effect on myogenesis was likely due to the dominant expression of alpha1 in myoblasts. These results were confirmed in C2C12 cells. To further evaluate the necessity of the AMPKalpha1 subunit for myogenesis in vivo, we prepared both DsRed AMPKalpha1 knockout myoblasts and enhanced green fluorescent protein (EGFP) wild-type myoblasts, which were cotransplanted into tibialis anterior muscle. A number of green fluorescent muscle fibers were observed, showing the fusion of engrafted wild-type myoblasts with muscle fibers; on the other hand, very few or no red muscle fibers were observed, indicating the absence of myogenic capacity of AMPKalpha1 knockout myoblasts. In summary, these results indicate that AMPK activity promotes myogenesis through a mechanism mediated by AMPKalpha1. |
