Salt dependent dimerisation of caldesmon.
Using analytical gel filtration (FPLC) we show here that avian gizzard caldesmon (chain molecular mass 150 kDa) self-associates to form end-to-end dimers. Increasing salt concentration promotes dimerisation: at 150 mM KCl, about 40% of the caldesmon was dimeric. Freshly gel filtered caldesmon had an actin gelating activity which decreased with increasing ionic strength. At 150 mM KCl, caldesmon at a 1:90 molar ratio to actin doubled the low shear viscosity of F-actin. Sixfold less filamin was required to produce the same effect.
D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D005895:Gizzard, Avian / Q000378:metabolism; D046911:Macromolecular Substances; D008958:Models, Molecular; D008970:Molecular Weight; D009130:Muscle, Smooth / Q000378:metabolism*; D009994:Osmolar Concentration; D011487:Protein Conformation; D014422:Turkeys
D002148:Calmodulin-Binding Proteins; D046911:Macromolecular Substances