title: Pax3/7BP is a Pax7- and Pax3-binding protein that regulates the proliferation of muscle precursor cells by an epigenetic mechanism.
abstract: In mouse skeletal muscles, Pax7 uniquely marks muscle satellite cells and plays some important yet unknown functions at the perinatal stage. To elucidate its in vivo functions, we initiated a yeast two-hybrid screening to look for Pax7-interacting proteins and identified a previously uncharacterized Pax7- and Pax3-binding protein (Pax3/7BP). Pax3/7BP is a ubiquitously expressed nuclear protein, enriched in Pax7+ muscle precursor cells (MPCs), and serves as an indispensable adaptor for Pax7 to recruit the histone 3 lysine 4 (H3K4) methyltransferase (HMT) complex by bridging Pax7 and Wdr5. Knockdown of Pax3/7BP abolished the Pax3/7-associated H3K4 HMT activity and inhibited the proliferation of Pax7+ MPCs from young mice both in culture and in vivo. Id3 and Cdc20 were direct target genes of Pax7 and Pax3/7BP involved in the proliferation of Pax7+ MPCs. Collectively, our work establishes Pax3/7BP as an essential adaptor linking Pax3/7 with the H3K4 HMT to regulate the proliferation of MPCs.
authors.affiliation: Division of Life Science, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, China.
authors.forename: Yarui
authors.initials: Y
authors.lastname: Diao
authors.forename: Xing
authors.initials: X
authors.lastname: Guo
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Li
authors.forename: Kun
authors.initials: K
authors.lastname: Sun
authors.forename: Leina
authors.initials: L
authors.lastname: Lu
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
authors.forename: Xinrong
authors.initials: X
authors.lastname: Fu
authors.forename: Han
authors.initials: H
authors.lastname: Zhu
authors.forename: Hao
authors.initials: H
authors.lastname: Sun
authors.forename: Huating
authors.initials: H
authors.lastname: Wang
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Wu
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D044127:Epigenesis, Genetic; D006657:Histones / Q000378:metabolism; D008239:Lysine / Q000378:metabolism; D008780:Methyltransferases / Q000378:metabolism; D051379:Mice; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D000072041:PAX3 Transcription Factor; D051763:PAX7 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D051761:Paired Box Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D006657:Histones; D000072041:PAX3 Transcription Factor; D051763:PAX7 Transcription Factor; D051761:Paired Box Transcription Factors; C497322:Pax7 protein, mouse; C068686:Pax3 protein, mouse; D008780:Methyltransferases; D008239:Lysine