The collapsin response mediator protein (CRMP) family of five cytosolic phosphoproteins are highly expressed throughout brain development. The functions of CRMPs encompass signal transduction in developmental guidance cues as well as multiple cellular and molecular events involved in apoptosis/proliferation, cell migration, and differentiation. In the adult brain, the expression of CRMPs is dramatically downregulated. However, CRMPs remain expressed in structures that retain their capacity fo