Identification of Nonviable Genes Affecting Touch Sensitivity in Caenorhabditis elegans Using Neuronally Enhanced Feeding RNA Interference

Caenorhabditis elegans senses gentle touch along the body via six touch receptor neurons. Although genetic screens and microarray analyses have identified several genes needed for touch sensitivity, these methods miss pleiotropic genes that are essential for the viability, movement, or fertility of the animals. We used neuronally enhanced feeding RNA interference to screen genes that cause lethality or paralysis when mutated, and we identified 61 such genes affecting touch sensitivity, including five positive controls. We confirmed 18 genes by using available alleles, and further studied one of them, tag-170, now renamed txdc-9. txdc-9 preferentially affects anterior touch response but is needed for tubulin acetylation and microtubule formation in both the anterior and posterior touch receptor neurons. Our results indicate that neuronally enhanced feeding RNA interference screens complement traditional mutageneses by identifying additional nonviable genes needed for specific neuronal functions.