Noncatalytic Function of ERK1/2 Can Promote Raf/MEK/ERK-mediated Growth Arrest Signaling

Kinase activity is known as the key biochemical property of MAPKs. Here, we report that ERK1/2 also utilizes its noncatalytic function to mediate certain signal transductions. Sustained activation of the Raf/MEK/ERK pathway induces growth arrest, accompanied by changes in cell cycle regulators (decreased retinoblastoma phosphorylation, E2F1 down-regulation, and/or p21CIP1 up-regulation) and cell type-specific changes in morphology and expression...