Figure 10.

Schematic Diagram Illustrates and Summarizes the Role and Signaling Pathway of PAK1 in Regulating Human SSCs

PAK1 is mediated by EGF, but not by GDNF or FGF2; PDK1, ZNF367, and KDR are the targets of PAK1. PAK1 binds to PDK1, and ZNF367 regulates PDK1 and KDR. PAK1 enhances the phosphorylation (phos-) of ERK1/2 and AKT, which facilitates directly or indirectly the entrance of phos-ERK1/2 and phos-AKT from cytoplasm to nuclei. PAK1 increases cyclin A level and stimulates human SSCs to enter S phase for DNA synthesis and cellular proliferation. Solid arrows, promote directly; dotted arrows, stimulate directly or indirectly; P in a circle, phosphorylate.