Polymorphism of myosin light chains. An electrophoretic and immunological study of rabbit skeletal-muscle myosins.
Antibodies specific for rabbit fast-twitch-muscle myosin LCIF light chain were purified by affinity chromatography and characterized by both non-competitive and competitive enzyme-linked immunosorbent assay (ELISA) and a gel-electrophoresis-derived assay (GEDELISA). The antibodies did not cross-react with myosin heavy chains, and were weakly cross-reactive with the LC2F [5,5'-dithio-(2-nitrobenzoic acid)-dissociated] light chain and with all classes of dissociated light chains (LC1Sa, LC1Sb and LC2S), as well as with the whole myosin, from hind-limb slow-twitch muscle. The immunoreactivity of myosins with a truly mixed light-chain pattern (e.g. vastus lateralis and gastrocnemius) correlated with percentage content of fast-twitch-muscle-type light chains. A more extensive immunoreactivity was observed with diaphragm and masseter myosins, which were also characterized, respectively, by a relative or absolute deficiency of LC1Sa light chain. Furthermore, it was found that the LC1Sb light chain of masseter myosin is antigenically different from its slow-twitch-muscle myosin analogue, and is immunologically related to the LC1F light chain. Rabbit masseter muscle from its metabolic and physiological properties and the content, activity and immunological properties of sarcoplasmic-reticulum adenosine triphosphatase, is classified as a red, predominantly fast-twitch, muscle. Therefore our results suggest that the two antigenically different iso-forms of LC1Sb light chain are associated with the myosins of fast-twitch red and slow-twitch red fibres respectively.
D000818:Animals; D000906:Antibodies / Q000276:immunology; D000918:Antibody Specificity; D000252:Calcium-Transporting ATPases / Q000276:immunology; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D008297:Male; D008406:Masseter Muscle / Q000032:analysis; D009124:Muscle Proteins / Q000032:analysis; D009218:Myosins / Q000145:classification / Q000276:immunology*; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000032:analysis
D000906:Antibodies; D009124:Muscle Proteins; D009218:Myosins; D000252:Calcium-Transporting ATPases