Transcription regulatory networks in Caenorhabditis elegans

sqt-1 encodes a cuticle collagen; during larval and adult development, sqt-1 activity is required, likely redundantly, for normal cuticle, and hence organismal, morphology; sqt-1 mRNA abundance oscillates during larval development, peaking at one point during each larval stage and peaking again in adults; sqt-1 transcripts are also detected in animals at the L1-L2d molt; in the temporally distinct waves of collagen gene expression that occur during larval development, sqt-1 mRNA appears to be synthesized during the second, or intermediate, stage, just very slightly earlier than sqt-3/col-1 and dpy-13; SQT-1 protein is detected in cuticle extracts from L2, L3, and L4 larvae, and from adults, but is not detected in extracts from L1 or dauer larvae; sqt-1 interacts genetically with a number of genes also required for normal cuticle and organismal morphology, e.g., rol-6 and lon-3, which also encode cuticular collagens.

sre-1 encodes a putative seven transmembrane chemoreceptor; an SRE-1::GFP reporter is expressed in the ADL and ASJ amphid sensory neurons.

nhx-2 encodes a sodium/proton exchanger expressed in the apical membranes of intestinal cells; NHX-2 is required for normally high growth rates, and for propagation or maintenance of the germline, NHX-2 is thought to prevent intracellular acidification by catalysing the electroneutral exchange of extracellular sodium for an intracellular proton.

B0511.12 encodes an ortholog of Drosophila PECANEX, and thus may participate in GLP-1/LIN-12 signalling.

pgl-2 encodes a novel protein of 532 amino acids that, in C. elegans, is one of three PGL protein family members; PGL-2 associates with P granules during postembryonic development; PGL-2 interacts with PGL-1, an additional P granule component, in yeast two-hybrid assays, but neither protein is required for proper localization of the other.