The Ras oncogene regulates cellular proliferation, differentiation, transformation, and
survival through multiple downstream signals. Ras signals through its effector
phosphoinositide 3 (PI3) kinase to the Pak protein kinase (p65 pak), but the steps from Ras
to Pak remain to be elucidated. PI3 kinase can stimulate the small G protein, Rac, a direct
activator of Pak, as well as the Akt proto-oncogene, a serine-threonine protein kinase. We
found that activated Akt stimulated Pak, whereas a dominant negative Akt inhibited Ras …