Effect of heat shock on acetylcholinesterase activity in chick muscle cultures

The effect of heat shock was studied on the acetylcholinesterase activity of chick muscle primary cultures. In cultures transferred from 37°C to 45°C, a sharp drop in activity was followed by rapid spontaneous recovery. The time of onset of recovery resembled the time needed for expression of heat shock proteins. In cultures exposed to heat shock at 45°C and allowed to recover at 37°C, reappearance of acetylcholinesterase activity did not involve de novo protein synthesis since it was not prevented by cycloheximide. Our data raise the possibility of a role for heat shock proteins as molecular chaperones in rescuing heat-denaturing acetylcholinesterase.