Structure and expression of the gsa-1 gene encoding a G protein alpha(s) subunit in C. elegans.

The heterotrimeric guanine nucleotide-binding proteins (G proteins) act as switches in the signal transduction from cell surface receptors to a variety of effectors. Among them, Gs proteins stimulate adenylate cyclase activities and regulate ion channels in mammals. We identified the gsa-1 gene encoding a G protein alpha subunit in the nematode Caenorhabditis elegans. The predicted product consists of 375 amino acid residues, 66% of which are identical with those of a mammalian Gs(alpha) subunit. The gsa-1 gene was physically mapped near the left end of chromosome I. A gsa-1/lacZ fusion gene was expressed in many cells in embryos, larvae and adults, including neurons, body wall muscle cells and muscle cells of the pharynx and the vulva. The results presents a basis for genetic studies of the gsa-1 gene.