Figure 5 TWK-7 is expressed in ventral nerve cord, head, and tail neurons. (A) Cytosolic DsRed expression driven by the
twk-7 promoter is overlaid withthe cholinergic neuron-specific cytosolic GFP expression mediated by the
unc-17 promoter. Coexpression is indicated by yellow color. (B) Maximumprojection of a z-series through the head region revealed that DsRed fluorescence is seen in cholinergic and noncholinergic head neurons. (C) Maximum projection of a z-series through the cholinergic region of the ventral nerve cord. Detailed coexpression analyses of TWK-7- and UNC-17-expressing cells in the ventral nerve cord indicate that TWK-7 is present in the cholinergic A-, AS-, and B-type motor neurons as well as in UNC-172 cells. According to their stereotypic positions, these were identified as GABAergic D-type motor neurons. In addition, TWK-7 expression is seen in unidentified tail neurons. (D) Maximum projection of a z-series through the cholinergic region of the ventral nerve cord. Expression of a TWK-7::mCherry fusion protein, which includes the entire TWK-7 channel protein, leads to a punctate subcellular and membrane-associated localization. (E) Coexpression of cytosolic GFP is driven by the cholinergic neuron-specific
unc-17 promoter.