title: Mitochondrial oxidative phosphorylation system is recruited to detergent-resistant lipid rafts during myogenesis.
abstract: Since detergent-resistant lipid rafts play important roles in the signal transduction for myogenesis, their comprehensive proteomic analysis could provide new insights to understand their function in myotubes. Here, the detergent-resistant lipid rafts were isolated from C2C12 myotubes and analyzed by capillary RPLC/MS/MS. Among the 327 proteins (or protein groups) identified, 28% were categorized to the plasma membrane or raft proteins, 29% to mitochondria, 20% to microsomal proteins, 10% to other proteins, and 13% to unknown proteins. The localization of oxidative phosphorylation (OXPHOS) complexes in the sarcolemma lipid rafts was further confirmed from C2C12 myotubes by cellular fractionation, surface-biotin labeling, immunofluorescence, and lipid raft fractionation. After adding exogenous cytochrome c, the sarcolemma isolated from myotubes had an ability to consume oxygen in the presence of NADH or succinate. The generation of NADH-dependent extracellular superoxide was increased by inhibiting or downregulating OXPHOS I, III, and IV in myotubes, indicating that OXPHOS proteins are major sources for extracellular ROS in skeletal muscle. With all these data, we can conclude that OXPHOS proteins are associated with the sarcolemma lipid rafts during C2C12 myogenesis to generate extracellular ROS.
authors.affiliation: School of Life Sciences and Biotechnology, Korea University, Seoul, Korea.
authors.forename: Bong-Woo
authors.initials: BW
authors.lastname: Kim
authors.forename: Joong-Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Hyo-Jung
authors.initials: HJ
authors.lastname: Choo
authors.forename: Chang Seok
authors.initials: CS
authors.lastname: Lee
authors.forename: Soon-Young
authors.initials: SY
authors.lastname: Jung
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Yi
authors.forename: Young-Mi
authors.initials: YM
authors.lastname: Ham
authors.forename: Joo-Hyung
authors.initials: JH
authors.lastname: Lee
authors.forename: Jin
authors.initials: J
authors.lastname: Hong
authors.forename: Min-Ju
authors.initials: MJ
authors.lastname: Kang
authors.forename: Sung-Gil
authors.initials: SG
authors.lastname: Chi
authors.forename: Seok-Won
authors.initials: SW
authors.lastname: Hyung
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Lee
authors.forename: Hwan Myung
authors.initials: HM
authors.lastname: Kim
authors.forename: Bong Rae
authors.initials: BR
authors.lastname: Cho
authors.forename: Do-Sik
authors.initials: DS
authors.lastname: Min
authors.forename: Gyesoon
authors.initials: G
authors.lastname: Yoon
authors.forename: Young-Gyu
authors.initials: YG
authors.lastname: Ko
mesh_terms: D000818:Animals; D002460:Cell Line; D003902:Detergents / Q000494:pharmacology*; D021962:Membrane Microdomains / Q000187:drug effects* / Q000378:metabolism*; D051379:Mice; D008928:Mitochondria / Q000378:metabolism*; D024510:Muscle Development; D010100:Oxygen / Q000378:metabolism*; D010766:Phosphorylation; D040901:Proteomics
chemical_list: D003902:Detergents; D010100:Oxygen