Fig. 6. C3 transferase impairs laminin-induced AChR clustering. (A) To confirm the results found with RhoN19 on laminin-induced AChR clustering, C3 transferase was added to C2 myotubes 3 hours prior to overnight laminin (10 nM) treatment. The effects on AChR surface distribution were examined by confocal microscopy of cultures surface-labeled with TMR-Bgt. C3 impairs the ability of agrin and laminin to form AChR clusters (b,d) compared with cells that were not treated with C3 (a,c). (B) Quantitative analysis of the effect of C3 on clustering of AChR clearly shows that inactivation of Rho impairs the formation of AChR clusters in response to laminin (10 nM) and agrin (5 nM) (error bars represent ±s.e.m.; n=100 cells from five or more separate platings).