The in vitro motility activity of β-cardiac myosin depends on the nature of the β-myosin heavy chain gene mutation in hypertrophic cardiomyopathy

摘要: Several mutations in the β-myosin heavy chain gene cause hypertrophic cardiomyopathy. This study investigates (1) vitro velocities of translocation fluorescently-labelled actin by purified from soleus muscle 30 cardiomyopathy patients with seven distinct mutations: Thr124Ile, Tyr162Cys, Gly256Glu, Arg403Gln, Val606Met, Arg870His, and Leu908Val mutations; (2) motility activity cardiac biopsies same patients. The velocity or 22 normal controls was 0.48 ± 0.09 μm s−1. By comparison, reduced all (range, 0.112 0.041 to 0.292 0.066 s−1). Notably, Tyr162Cys Arg403Gln demonstrated significantly lower sliding velocities: 0.123 0.044, s−1, respectively. four mutation had a similar actomyosin compared their (0.127 0.045 s−1 versus 0.119 0.068 respectively). Since these lie several functional domains, it is likely that mechanisms inhibitions are different