Figure 5
From: Evolutionary conservation and changes in insect TRP channels
NvHsTRPA is a thermo-sensitive TRP channel. (A) Localization of V5 and His epitope-tagged NvHsTRPA protein in HEK293 cells visualized by immunofluorescence. (B) Detection of the epitope-tagged NvHsTRPA protein by Western blot. The lysates of HEK293 cells transfected with empty vector (Mock) and NvHsTRPA expression vector (NvHsTRPA) were analyzed by Western blot. Arrowhead indicates NvHsTRPA protein band, while asterisk shows the heat aggregated protein band. The NvHsTRPA expressing cells were treated with (+) or without (-) tunicamycin (Tun). The positions of MW markers are shown on the left in kDa. (C) Heat elicits inward current activation in a NvHsTRPA-expressing HEK293 cell (NvHsTRPA, left panel) at -60 mV holding potential in a whole-cell patch-clamp mode (n = 6). A standard bath solution and Cs-Asp/Ca2+(-) pipette solution were used. NvHsTRPA is activated by temperature increase, and quickly inactivated by constant heat application. Desensitization of the channel is also observed by repetitive heat applications. The current activation is not observed with the mock-transfected cells (Mock, right panel). (D) Current--voltage relationship of heat evoked current exhibits dual rectification with a slight positive reversal potential. Heat-dependent shifts of the liquid junction potentials (ΔJPH) were not corrected in the plot (n = 9). A standard bath solution and Cs-Asp/Ca2+(-) pipette solution were used.