ジャーナル: Proc Natl Acad Sci U S A / 年: 2011 タイトル: Direct visualization of myosin-binding protein C bridging myosin and actin filaments in intact muscle. 著者: Pradeep K Luther / Hanspeter Winkler / Kenneth Taylor / Maria E Zoghbi / Roger Craig / Raúl Padrón / John M Squire / Jun Liu / 要旨: Myosin-binding protein C (MyBP-C) is a thick filament protein playing an essential role in muscle contraction, and MyBP-C mutations cause heart and skeletal muscle disease in millions worldwide. ...Myosin-binding protein C (MyBP-C) is a thick filament protein playing an essential role in muscle contraction, and MyBP-C mutations cause heart and skeletal muscle disease in millions worldwide. Despite its discovery 40 y ago, the mechanism of MyBP-C function remains unknown. In vitro studies suggest that MyBP-C could regulate contraction in a unique way--by bridging thick and thin filaments--but there has been no evidence for this in vivo. Here we use electron tomography of exceptionally well preserved muscle to demonstrate that MyBP-C does indeed bind to actin in intact muscle. This binding implies a physical mechanism for communicating the relative sliding between thick and thin filaments that does not involve myosin and which could modulate the contractile process.