Involvement of hydrophobic residues in heat-induced gelation of myosin tail subfragments from rabbit skeletal muscle.

Myosin solutionsform gels when heated under appropriate conditions.1>2)The process of heat-induced gelation of skeletal muscle myosin at high ionic strength was explained as the irreversible aggregation of the globular head segments of myosin molecules and network formation resulting from the unfolding of helical tail segments.3)Proteolysis of myosin with trypsin or chymotrypsin produces tail sub fragments such as light meromyosin(LMM) and rods.4'5)The tail portion of myosin heavy chain (MHC) is composed of repetitive oc-helical sequences that assemble in register with another MHCto form a coiled coil.6'7)The repetitive sequence of myosin tail segments included 28-amino acid repeats of seven-residue units with hydrophobic residues at specific positions.This organization provide a hydrophobic surface