Identification of a complex between alpha-actinin and the intermediate filament subunit skeletin in bovine heart Purkinje fibres.
A three-dimensional cytoskeleton, morphologically composed of intermediate filaments, desmosomes, and Z-disks, remains in bovine heart Purkinje fibres after extraction with Triton X-100 and low and high ionic strength solutions. Biochemically this cytoskeleton mainly consists of skeletin (Mr approximately 55 000) and of alpha-actinin (Mr approximately 95 000). Minor high molecular weight components are also present. By gel electrophoresis-derived enzyme-linked immunosorbent assay (GEDELISA) we show here that a 150 000-dalton component is a complex of alpha-actinin and skeletin. Furthermore, this 150 000-dalton component has now been purified and can be converted into 95 000- and 55 000-dalton subunits by reduction with a high concentration of beta-mercaptoethanol and heating. We also show that solubilized pure skeletin and pure alpha-ctinin from Purkinje fibres, after mixing, partly form a stable complex with a molecular weight of about 150 000 daltons.
D000185:Actinin / Q000032:analysis*; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D003599:Cytoskeleton / Q000032:analysis*; D003893:Desmin; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006329:Heart Conduction System / Q000648:ultrastructure*; D007381:Intermediate Filament Proteins / Q000032:analysis* / Q000302:isolation & purification; D008970:Molecular Weight; D009124:Muscle Proteins / Q000032:analysis*; D011690:Purkinje Fibers / Q000032:analysis / Q000648:ultrastructure*
D000596:Amino Acids; D003893:Desmin; D007381:Intermediate Filament Proteins; D009124:Muscle Proteins; D000185:Actinin