Figure 3. Disruption of c-Src SH2- or SH3-dependent associations inhibits de novo cortical actin assembly.

ACCs were permeabilized in the presence of Alexa Fluor 488 G-actin, 10 µM free Ca²⁺ and 5 µM GST alone or growing concentrations of cSrc SH2-GST (SH2) or cSrc SH3-GST (SH3). (A–B) Representative images showing the new formation of cortical actin in cells permeabilized without peptides (non-treated) and in the presence of GST (A), or with different amounts of SH2 (B, left panel) or SH3 (B, right panel). Scale bar  = 10 µm. (C) Quantification demonstrates that 0.1 µM of c-Src SH2 or SH3 domain is sufficient to significantly disrupt Ca²⁺-dependent actin polymerization in ACCs. Data are means ± SEM of fluorescence intensity from at least 10 cells per each condition. *p<0.05 compared to GST.