[Enhancement of the combination of F-actin and alpha-actinin association in the presence of 1,2-propanediol].

The influence of 1,2-propanediol on the G-actin/F-actin equilibrium has been studied previously. We report here its effect on the crosslinking of actin filaments by alpha-actinin. Capillary viscometry experiments indicate a marked increase in the viscosity of F-actin/alpha-actinin solutions in the presence of this solvent, with a rise of the gel point temperature. Gel electrophoresis obtained after high-speed sedimentation of these proteins showed an enhancement of the alpha-actinin/actin filaments association. Propanediol-induced perturbations of interactions between microfilaments and actin-binding proteins might help explain the variability of its cryoprotective efficiency for the preservation of various cells.