Myogenic basic helix-loop-helix transcription factors regulate PGC-1α during terminal myogenic differentiation

• Main Authors: Kai-min Huang, 黃凱民
• Other Authors: 陳盛良
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/22729909948641516355

碩士 === 國立中央大學 === 生命科學研究所 === 95 === Skeletal muscle are generally classified as two types – type I (slow - twitch) and type II (fast - twitch). The former is rich in mitchondria and thus provides constant ATP through oxidative metabolism. The latter depends on the glycolytic metabolism as the energy source. PGC-1α is a transcriptional coactivator mainly expressed in the slow-twitch fibers. Previous studies indicated that over-expression of PGC-1α promotes the conversion from fast-twitch fibers to slow-twitch fibers. According to previous observations, we know that the E2-box on the PGC-1α promoter is essential for MyoD-mediated transactivation. In this study, we found that Stra13, a putative E1-box binding transcriptional repressor, repressed the MyoD mediated PGC-1α promoter activation. The interaction between MyoD and Stra13 was almost undetectable by GST-Pull down assay and EMSA. In addition, over-expression of P/CAF, but not CBP, can rescue the Stra13-mediated repression. These data suggest that Stra13 represses MyoD-mediated PGC-1 activation by sequestering P/CAF from MyoD.