| First Author | Gomez K | Year | 2021 |
| Journal | Mol Brain | Volume | 14 |
| Issue | 1 | Pages | 20 |
| PubMed ID | 33478555 | Mgi Jnum | J:303868 |
| Mgi Id | MGI:6510037 | Doi | 10.1186/s13041-020-00714-1 |
| Citation | Gomez K, et al. (2021) Non-SUMOylated CRMP2 decreases NaV1.7 currents via the endocytic proteins Numb, Nedd4-2 and Eps15. Mol Brain 14(1):20 |
| abstractText | Voltage-gated sodium channels are key players in neuronal excitability and pain signaling. Functional expression of the voltage-gated sodium channel NaV1.7 is under the control of SUMOylated collapsin response mediator protein 2 (CRMP2). When not SUMOylated, CRMP2 forms a complex with the endocytic proteins Numb, the epidermal growth factor receptor pathway substrate 15 (Eps15), and the E3 ubiquitin ligase Nedd4-2 to promote clathrin-mediated endocytosis of NaV1.7. We recently reported that CRMP2 SUMO-null knock-in (CRMP2(K374A/K374A)) female mice have reduced NaV1.7 membrane localization and currents in their sensory neurons. Preventing CRMP2 SUMOylation was sufficient to reverse mechanical allodynia in CRMP2(K374A/K374A) female mice with neuropathic pain. Here we report that inhibiting clathrin assembly in nerve-injured male CRMP2(K374A/K374A) mice precipitated mechanical allodynia in mice otherwise resistant to developing persistent pain. Furthermore, Numb, Nedd4-2 and Eps15 expression was not modified in basal conditions in the dorsal root ganglia (DRG) of male and female CRMP2(K374A/K374A) mice. Finally, silencing these proteins in DRG neurons from female CRMP2(K374A/K374A) mice, restored the loss of sodium currents. Our study shows that the endocytic complex composed of Numb, Nedd4-2 and Eps15, is necessary for non-SUMOylated CRMP2-mediated internalization of sodium channels in vivo. |
