Calmodulin regulates current density and frequency-dependent inhibition of sodium channel Nav1.8 in DRG neurons.

  title={Calmodulin regulates current density and frequency-dependent inhibition of sodium channel Nav1.8 in DRG neurons.},
  author={Jin-Sung Choi and Andy Hudmon and Stephen G. Waxman and Sulayman D. Dib-Hajj},
  journal={Journal of neurophysiology},
  volume={96 1},
Sodium channel Nav1.8 produces a slowly inactivating, tetrodotoxin-resistant current, characterized by recovery from inactivation with fast and slow components, and contributes a substantial fraction of the current underlying the depolarizing phase of the action potential of dorsal root ganglion (DRG) neurons. Nav1.8 C-terminus carries a conserved calmodulin-binding isoleucine-glutamine (IQ) motif. We show here that calmodulin coimmunoprecipitates with endogenous Nav1.8 channels from native DRG… 

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