Figure 1. aex genes are expressed in neuronal and nonneuronal tissues of C. elegans. (A) Diagram of the C. elegans DMP. First, a posterior contraction (pBoc) forces the intestinal contents to the anterior end of the worm. About 3 sec later, an anterior contraction (aBoc) forces intestinal contents to the posterior end. Within about 1 sec of the aBoc, an enteric muscle contraction in the tail leads to excretion of intestinal contents (Exp). Arrowheads indicate the location of AVL and DVB GABAergic neurons. (B-D)
aex-4 is expressed in the intestine. (B) GFP is detected solely in the intestinal nuclei in a transgenic animal that expresses nuclear localized GFP under the
aex-4 promoter. (C, D) Functional AEX-4::GFP fusion is expressed in intestinal cells and enriched at the cell surface (arrows; red indicates autofluorescence). (C) Confocal slice through the middle of the intestine. (D) Cell surface view of the posterior intestinal cell. Bright field images are provided for orientation. (E, F) Intestinal AEX-5::VENUS (which is driven by the intestinal promoter Pvha-6) is secreted from the intestine and taken up by coelomocytes (CC, arrows; red indicates autofluorescence). (G'-L')
aex-2 is expressed in the GABAergic neurons AVL and DVB as well as in enteric muscles. (G and I) AEX-2::mCherry is detected in the nerve ring (NR, arrow), ciliary sensory processes (CA, open arrow), nerve cord (I), and head mesodermal cell (HMC, arrowhead). (H) AEX-2::mCherry is expressed in the intestinal muscle (IM, arrow) and anal depressor (AD, arrowhead). (J'-L') mCherry expressed under the
aex-2 promoter is detected in AVL (J-L, arrow) and DVB (J''-L'', arrow) GABAergic neurons. AEX-2::mCherry signal does not significantly overlap with GABAergic GFP in the ventral nerve cord (J'-L'). (Scale bar, 20 um.) See SI Text for transgenes and clones.