Role of collapsin response mediator protein-2 in neurite outgrowth of PC12 cells.

Collapsin response mediator proteins (CRMPs) are involved in cell differentiation and axonal growth. In this study, we investigated neurite outgrowth and the expression of CRMP-2 in PC12 cells. Nondifferentiated PC12 cells hardly express CRMP-2, but the expression of CRMP-2 increases with neurite outgrowth. We established a stable CRMP-2-overexpressing PC12 cell line and found that PC12 cells, which constitutively overexpress CRMP-2, were unable to extend neurites after stimulation with the nerve growth factor or the neural cell adhesion molecule, a procedure that promotes neurite outgrowth in untransfected cells. In contrast, a PC12 cell line deficient in CRMP-2 extends neurites after the stimulation of nerve growth factor or neural cell adhesion molecule.