Immunofluorescence analysis showed that the earliest myosin detectable in both the embryonic chicken heart and somitic myotome, the precursor to skeletal muscle, was strongly reactive with two different monoclonal antibodies specific for the heavy chain of cardiac ventricular myosin, but it showed no reactivity with affinity-purified polyclonal antibodies specific for the heavy chains of either...

Hypertrophic cardiomyopathy (HCM) is the most frequently occurring inherited cardiovascular disease. It is caused by mutations in genes encoding the force-generating machinery of the cardiac sarcomere, including human β-cardiac myosin. We present a detailed characterization of the most debated HCM-causing mutation in human β-cardiac myosin, R403Q. Despite numerous studies, most performed with n...

Immune responses against cardiac myosin and group A streptococcal M protein have been implicated in the pathogenesis of rheumatic heart disease. Although cardiac myosin is known to produce myocarditis in susceptible animals, it has never been investigated for its role in production of valvular heart disease, the most serious sequelae of group A streptococcal infection in acute rheumatic fever. ...

Inherited cardiomyopathies are a common form of heart disease that are caused by mutations in sarcomeric proteins with beta cardiac myosin (MYH7) being one of the most frequently affected genes. Since the discovery of the first cardiomyopathy associated mutation in beta-cardiac myosin, a major goal has been to correlate the in vitro myosin motor properties with the contractile performance of ca...

Previous reports from our group have demonstrated the association of molecular mimicry between cardiac myosin and the immunodominant Trypanosoma cruzi protein B13 with chronic Chagas' disease cardiomyopathy at both the antibody and heart-infiltrating T cell level. At the peripheral blood level, we observed no difference in primary proliferative responses to T. cruzi B13 protein between chronic ...

• Characterization of the myocardial contractile proteins has been undertaken in an attempt to define biochemical mechanisms responsible for the physiological dissimilarities between cardiac and skeletal muscle. These functional differences include the lesser tension generated by cardiac muscle,' different actions of inotropic agents,' and the relative slowness of onset of the active state of c...

More than 30 missense mutations in the b -cardiac myosin heavy chain gene have been shown to be responsible for familial hypertrophic cardiomyopathy. To clarify the effects of these point mutations on myosin motor function, we expressed wild-type and mutant human b -cardiac myosin heavy chains in insect cells with human cardiac light chains. The wild-type myosin was well purified with similar e...

More than 30 missense mutations in the beta-cardiac myosin heavy chain gene have been shown to be responsible for familial hypertrophic cardiomyopathy. To clarify the effects of these point mutations on myosin motor function, we expressed wild-type and mutant human beta-cardiac myosin heavy chains in insect cells with human cardiac light chains. The wild-type myosin was well purified with simil...

• Characterization of the myocardial contractile proteins has been undertaken in an attempt to define biochemical mechanisms responsible for the physiological dissimilarities between cardiac and skeletal muscle. These functional differences include the lesser tension generated by cardiac muscle,' different actions of inotropic agents,' and the relative slowness of onset of the active state of c...

Cardiac myosin was isolated from the hearts of seven dogs with naturally occurring heart failure. Six of the seven dogs had heart failure secondary to acquired mitral valvular insufficiency; the seventh was believed to have a primary myocardiopathy. The characteristics of this myosin were compared to cardiac myosin from a group of normal dogs studied concurrently. Cardiac myosin was extracted f...