CD2AP is a positive regulator of AKT phosphorylation and increases p85 recruitment to TrkA complexes. A, Western blot assay of protein samples from NGF-treated PC12 cells assessed for phospho-AKT (pAKT), total-AKT (tAKT), phospho-ERK (pERK), total-ERK (tERK), and loading control (GAPDH) following transfection with scramble control (Sc) or CD2AP siRNA. B, Densitometric quantification of pAKT and pERK, relative to tAKT and tERK, respectively. C, Western blot assay of p85 and TrkA immunoprecipitates following transfection with scramble control (Sc) or CD2AP (C) siRNA. CD2AP, TrkA, and p85 protein concentrations are shown in input (In) and bound fractions. D, Quantification of TrkA:p85 colocalization in growth cones following transfection with GFP (E–G), GFP-CD2AP (H–J), scramble control (K–M), or CD2AP siRNA (N–P). G, J, M, P, Representative images from the 3D colocalization analyses are shown for each condition. *Statistically significant changes compared with the respective control (ANOVA, followed by t test compared with control).