Figure 2. Native Na_v1.8 sodium channels are colocalized with and phosphorylated by PKCε.

(A) Na_v1.8 (green) and PKCε (red) colocalize in small- and medium-sized DRG neurons (yellow). Areas labeled 1 and 2 in the merged image are shown at higher magnification in the bottom panels. Scale bar: 200 μm (top); 25 μm (bottom). (B) Lumbar DRG lysates were immunoblotted directly (Input) or immunoprecipitated (IP) with PKCε, IgG, or anti-Na_v1.8 antibodies, and then the immunoprecipitates were subjected to Western blot (WB) analysis with anti-PKCε antibody. (C) PKCε-mediated thiophosphorylation of proteins immunoprecipitated from lumbar DRG lysates with anti-Na_v1.8 or control IgG and assayed in the presence or absence of the PKC inhibitor bisindolylmaleimide I (BIS; top). The Western blot in the bottom panel shows that equal amounts of immunoprecipitated Na_v1.8 were used in the kinase assay. Thiophos. ester, thiophosphate ester.