(A). sax-7(nj48) mutants had severely defective PVD morphology. (B) The mutant phenotype could be fully rescued by expressing SAX-7 in the hypodermal cells using the dpy-7 promoter. (C, D) SAX-7 was expressed in neurons and the hypodermal cells (D) and localized subcellularly to two lateral stripes in the hypodermal cell (C). (E, F) The PVD morphology defects in mnr-1(wy758) (E) were also fully rescued by expressing MNR-1 in the hypodermal cell using the dpy-7 promoter (F). (G, H) MNR-1 was only expressed in the hypodermis (H) and showed no obvious subcellular localization (G). (I) Expression of SAX-7 in hypodermal cells rescued the mutant phenotype in all transgenic animals, whereas no rescue was observed when SAX-7 was expressed in the PVD neuron using the ser2prom3 promoter, or in the muscles using the myo-2 promoter. (J) Expression of MNR-1 in the hypodermal cells also rescued the mnr-1(wy758) mutant phenotype, while expression in PVD using the ser2prom3 promoter failed to rescue. (K) PVD morphology in sax-7(nj48); mnr-1(wy758) double mutants was indistinguishable from the single mutants. Arrows in (C): SAX-7 sublateral stripes in hypodermal cells. Arrowheads in (C): SAX-7 expressed in the ALM and PLM neurons. Arrow head in (D) and (H): Fluorescent labeling of the hypodermal cells. Scale bar: 10 μm. Error bars: Standard error of the mean. *** is p<0.001 by student’s T-test. N=20 for all genotypes. See also Figure S2.