Differential expression of Cdk5-phosphorylated CRMP2 following a spared nerve injury

Abstract Effective treatment of high-impact pain patients is one of the major stated goals of the National Pain Strategy in the United States. Identification of new targets and mechanisms underlying neuropathic pain will be critical in developing new target-specific medications for better neuropathic pain management. We recently discovered that peripheral nerve injury-induced upregulation of an axonal guidance phosphoprotein collapsin response mediator protein 2 (CRMP2) and the N-type voltage-gated calcium (CaV2.2) as well as the NaV1.7 voltage-gated sodium channel, correlates with the development of neuropathic pain. In our previous studies, we found that interfering with the phosphorylation status of CRMP2 is sufficient to confer protection from chronic pain. Here we examined the expression of CRMP2 and CRMP2 phosphorylated by cyclin-dependent kinase 5 (Cdk5, on serine residue 522 (S522)) in sciatic nerve, nerve terminals of the glabrous skin, and in select subpopulations of DRG neurons in the SNI model of neuropathic pain. By enhancing our understanding of the phosphoregulatory status of CRMP2 within DRG subpopulations, we may be in a better position to design novel pharmacological interventions for chronic pain.