Fig. 3

Calpain-1 autolysis and calpain-3 reduction in IBM. a Representative immunoblot demonstrating prominent autolysis of 80 kDa native calpain-1 to proteolytically active calpain isoforms. b Quantification of 78 and 76 kDa calpain-1 band areas divided by total calpain-1. c Representative western blot of native calpain-3 expression. d Quantified expression of native calpain-3 protein levels. e Transcript expression of CAPN3 gene as determined by RNA-seq. Graphed data expressed as mean + SEM. N of 5, 4, and 7 for non-myositis controls (CON), DM, and IBM, respectively; *P < 0.05 vs CON; ^† P < 0.05 vs DM