Superprecipitation of actomyosin with p-chloromercuribenzoate-modified myosin reconstituted from rabbit skeletal muscle.
Myosin head modified with p-chloromercuribenzoate (CMB) forms rigor-like complex with actin in the presence of ATP. Actomyosins with CMB-modified myosin were reconstituted to study the effect of rigor-like complexes on superprecipitation. As native myosin was increasingly replaced by CMB-modified myosin, superprecipitation of the actomyosin was strongly suppressed. Further, the suppression of superprecipitation occurred in a different fashion depending on how CMB-modified myosin was incorporated in myosin filaments of the reconstituted actomyosin. The present results indicate that superprecipitation requires the dissociation of actin and myosin head to take place (i.e., the presence of molecular rearrangements of actomyosin network), and further suggest that superprecipitation is associated with dynamic rearrangements of actomyosin network along myosin filaments.
D000205:Actomyosin / Q000378:metabolism*; D000818:Animals; D002729:Chloromercuribenzoates / Q000494:pharmacology*; D007700:Kinetics; D009132:Muscles / Q000378:metabolism*; D015879:Myosin Subfragments / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D055503:Protein Multimerization; D011817:Rabbits; D020245:p-Chloromercuribenzoic Acid
D002729:Chloromercuribenzoates; D015879:Myosin Subfragments; D020245:p-Chloromercuribenzoic Acid; D000205:Actomyosin; D009218:Myosins