Inhibition of Insulin-induced Activation of Akt by a Kinase-deficient Mutant of the ε Isozyme of Protein Kinase C

摘要: Abstract Akt, also known as protein kinase B, is a protein-serine/threonine that activated by growth factors in phosphoinositide (PI) 3-kinase-dependent manner. Although Akt mediates variety of biological activities, the mechanisms which its activity regulated remain unclear. The potential role e isozyme C (PKC) activation induced insulin has now been examined. Expression kinase-deficient mutant PKCe (eKD), but not wild-type or mutants PKCα PKCλ, with use adenovirus-mediated gene transfer inhibited phosphorylation and Chinese hamster ovary cells L6 myotubes. Whereas eKD did affect stimulation PI 3-kinase activity, constitutively active were eKD, suggesting affects signaling downstream 3-kinase. PDK1 (3′-phosphoinositide-dependent 1) thought to participate activation. Overexpression an adenovirus vector Akt; inhibited, whereas had no effect on, these actions PDK1. These results suggest inhibits insulin-induced interfering ability phosphorylate Akt.