277, 44417-44430) we reported that phosphorylation of p85 betaPIX, a guanine nucleotide exchange factor (GEF) for Rac1/Cdc42, is a signal for translocation of the PIX complex to neuronal growth cones and is associated with basic fibroblast growth factor (bFGF)-induced neurite outgrowth.     ///    "However, the issue of whether p85 betaPIX phosphorylation affects GEF activity on Rac1/Cdc42 is yet to be explored. "