Oakley Cecily E, Chamoun Jean, Brown Louise J, Hambly Brett D
Pathology Discipline, School of Medical Science and Bosch Institute, University of Sydney, NSW 2006, Australia.
Int J Biochem Cell Biol. 2007;39(12):2161-6. doi: 10.1016/j.biocel.2006.12.008. Epub 2007 Jan 20.
Myosin binding protein C (MyBPC) is a sarcomeric protein whose role in sarcomere structure and regulation of contraction is currently under investigation. It is a member of the immunoglobulin superfamily and is found in the C-zone of the A-band of the sarcomere. The elongated structure of MyBPC is composed of a series of immunoglobulin and fibronectin domains, with the C-terminal domains binding to the myosin thick filament and the N-terminal domains interacting with the myosin subfragment-2 (S2) neck region and possibly the actin thin filament. The functions of MyBPC are to stabilise the sarcomere structure and to regulate contraction. When phosphorylated near its N-terminus, MyBPC no longer binds myosin-S2, causing an increase in the ordering of the myosin heads, ATPase activity, F(max) and Ca(2+) sensitivity of contraction. Mutations in MyBPC have been found to cause familial hypertrophic cardiomyopathy (FHC) and changes in MyBPC phosphorylation have been linked to cardiac ischaemia-reperfusion injury.
肌球蛋白结合蛋白C（MyBPC）是一种肌节蛋白，目前正在研究其在肌节结构和收缩调节中的作用。它是免疫球蛋白超家族的成员，存在于肌节A带的C区。MyBPC的细长结构由一系列免疫球蛋白和纤连蛋白结构域组成，其C末端结构域与肌球蛋白粗丝结合，N末端结构域与肌球蛋白亚片段2（S2）颈部区域相互作用，可能还与肌动蛋白细丝相互作用。MyBPC的功能是稳定肌节结构并调节收缩。当在其N末端附近磷酸化时，MyBPC不再与肌球蛋白-S2结合，导致肌球蛋白头部的有序性增加、ATP酶活性、F（max）和收缩的Ca（2+）敏感性增加。已发现MyBPC中的突变会导致家族性肥厚性心肌病（FHC），并且MyBPC磷酸化的变化与心脏缺血-再灌注损伤有关。
