title: Soluble guanylate cyclases act in neurons exposed to the body fluid to promote C. elegans aggregation behavior.
abstract: The genome of the nematode Caenorhabditis elegans encodes seven soluble guanylate cyclases (sGCs). In mammals, sGCs function as alpha/beta heterodimers activated by gaseous ligands binding to a haem prosthetic group. The principal activator is nitric oxide, which acts through sGCs to regulate diverse cellular events. In C. elegans the function of sGCs is mysterious: the worm genome does not appear to encode nitric oxide synthase, and all C. elegans sGC subunits are more closely related to mammalian beta than alpha subunits. Here, we show that two of the seven C. elegans sGCs, GCY-35 and GCY-36, promote aggregation behavior. gcy-35 and gcy-36 are expressed in a small number of neurons. These include the body cavity neurons AQR, PQR, and URX, which are directly exposed to the blood equivalent of C. elegans and regulate aggregation behavior. We show that GCY-35 and GCY-36 act as alpha-like and beta-like sGC subunits and that their function in the URX sensory neurons is sufficient for strong nematode aggregation. Neither GCY-35 nor GCY-36 is absolutely required for C. elegans to aggregate. Instead, these molecules may transduce one of several pathways that induce C. elegans to aggregate or may modulate aggregation by responding to cues in C. elegans body fluid.
authors.affiliation: The Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, United Kingdom.
authors.forename: Benny H H
authors.initials: BH
authors.lastname: Cheung
authors.forename: Fausto
authors.initials: F
authors.lastname: Arellano-Carbajal
authors.forename: Irene
authors.initials: I
authors.lastname: Rybicki
authors.forename: Mario
authors.initials: M
authors.lastname: de Bono
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D001826:Body Fluids / Q000378:metabolism*; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000378:metabolism*; D005247:Feeding Behavior / Q000502:physiology; D049452:Green Fluorescent Proteins; D006162:Guanylate Cyclase / Q000737:chemistry / Q000378:metabolism*; D008164:Luminescent Proteins; D009043:Motor Activity / Q000235:genetics* / Q000502:physiology; D009154:Mutation / Q000235:genetics; D009474:Neurons / Q000378:metabolism*; D017368:Protein Prenylation / Q000235:genetics / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012919:Social Behavior
chemical_list: D029742:Caenorhabditis elegans Proteins; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins; C488166:GCY-35 protein, C elegans; D006162:Guanylate Cyclase