Circadian rhythms and metabolism are tightly integrated, and rhythmic expression of metabolic factors is common in homeostatic processes. We measured the temporal changes in the expression of myogenic regulatory factors and expression and activity level of molecules involved in protein metabolism in skeletal muscles and livers in mice and examined the impact of fasting. Tissues were collected o...

The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first d...

Inflammation of the muscle invariably leads to muscle cell damage and impaired regeneration. Biomechanical signals play a vital role in the regulation of myogenesis in healthy and inflamed muscle. We hypothesized that biomechanical signals counteract the actions of proinflammatory mediators and upregulate the basic helix-loop-helix and MADS box transcription enhancer factor 2 (MEF2) families of...

Sequential activation of muscle-specific transcription factors is the critical basis for myogenic differentiation. However, the complexity of this process does not exclude the possibility that other molecules and systems are regulatory as well. We observed that myogenic differentiation proceeded through three distinct stages of proliferation, elongation and fusion, which are distinguishable by ...

Myogenic regulatory factors (MRFs), including Myf5, MyoD (Myod1) and Myog, are muscle-specific transcription factors that orchestrate myogenesis. Although MRFs are essential for myogenic commitment and differentiation, timely repression of their activity is necessary for the self-renewal and maintenance of muscle stem cells (satellite cells). Here, we define Ascl2 as a novel inhibitor of MRFs. ...

Chromatin remodeling by the SWI/SNF complex is required to activate the transcription of myogenic-specific genes. Our work addressed the details of how SWI/SNF is recruited to myogenic regulatory regions in response to differentiation signals. Surprisingly, the muscle determination factor MyoD and the SWI/SNF subunit BAF60c form a complex on the regulatory elements of MyoD-targeted genes in myo...

PAX3 is a member of the PAX3/7 subfamily of the paired box proteins. In vertebrates, Pax3 is essential for skeletal myogenesis by activating a cascade of transcriptional events that are necessary and sufficient for skeletal myogenesis. Four related basic helix-loop-helix transcription factors, MyoD, Myf5, Mrf4, and Myogenin, are targets of PAX3 and serve as myogenic regulatory factors. Although...