Satellite cells (SCs) sustain muscle growth and empower adult skeletal muscle with vigorous regenerative abilities. Here, we report that EZH2, the enzymatic subunit of the Polycomb-repressive complex 2 (PRC2), is expressed in both Pax7+/Myf5⁻ stem cells and Pax7+/Myf5+ committed myogenic precursors and is required for homeostasis of the adult SC pool. Mice with conditional ablation of Ezh2 in S...

The growth and repair of skeletal muscle after birth depends on satellite cells that are characterized by the expression of Pax7. We show that Pax3, the paralogue of Pax7, is also present in both quiescent and activated satellite cells in many skeletal muscles. Dominant-negative forms of both Pax3 and -7 repress MyoD, but do not interfere with the expression of the other myogenic determination ...

Rhabdomyosarcoma (RMS) is an aggressive childhood malignancy of neoplastic muscle-lineage precursors that fail to terminally differentiate into syncytial muscle. The most aggressive form of RMS, alveolar-RMS, is driven by misexpression of the PAX-FOXO1 oncoprotein, which is generated by recurrent chromosomal translocations that fuse either the PAX3 or PAX7 gene to FOXO1. The molecular underpinn...

To investigate the role of the translocation-associated gene Pax3:Fkhr in alveolar rhabdomyosarcomas, we generated a Cre-mediated conditional knock-in of Pax3:Fkhr into the mouse Pax3 locus. Exploring embryonic tumor cell origins, we replaced a Pax3 allele with Pax3:Fkhr throughout its expression domain, causing dominant-negative effects on Pax3 and paradoxical activation of the Pax3 target gen...

Neuroectodermal tumor cells, like neural crest (NC) cells, are pluripotent, proliferative, and migratory. We tested the hypothesis that genetic programs essential to NC development are activated in neuroectodermal tumors. We examined the expression of transcription factors PAX3, PAX7, AP-2alpha, and SOX10 in human embryos and neuroectodermal tumors: neurofibroma, schwannoma, neuroblastoma, mali...

BACKGROUND Although muscle dysfunction caused by unfamiliar lengthening contraction is one of most important issues in sports medicine, there is little known about the molecular events on regeneration process. The purpose of this study was to investigate the temporal and spatial expression patterns of myogenin, myoD, pax7, and myostatin after acute lengthening contraction (LC)-induced injury in...

Epigenetic processes in the development of skeletal muscle have been appreciated for over a decade. DNA methylation is a major epigenetic modification important for regulating gene expression and suppressing spurious transcription. Up to now, the importance of epigenetic marks in the regulation of Pax7 and myogenic regulatory factors (MRFs) expression is far less explored. In the present study,...

Myostatin and Pax7 have been well documented individually, however, the mechanism by which Myostatin regulates Pax7 is seldom reported. Here, based on muscle transcriptome analysis in Texel (Myostatin mutant) and Ujumqin (wild type) sheep across the five fetal stages, we constructed and examined the Myostatin-Pax7 pathways in muscle. Then we validated the signals by RNAi in the proliferating an...