The purpose of this research is to examine plasma membrane repair.
Muscle damage occurs when myofibers experience mechanical stress.
Plasma membrane resealing is an essential process which prevents cell death following tearing of the plasma membrane. Our lab has been studying plasma membrane resealing in sea urchin eggs and 3T3 fibroblast cells by measuring the rate of dye loss after cell micropuncture. Previous studies with muscle cells have demonstrated that plasma membrane resealing requires an external calcium concentration which is approximately 10 fold less than physiological calcium level. These studies will determine whether plasma membrane resealing in myotubes acts in a manner similar to that observed in sea urchin eggs and 3T3 fibroblast cells. Cultured myotubes will be injected with botulinum type A, B, and C1, which proteolyze synaptobrevin, SNAP-25, and syntaxin respectively.