title: RIC-8 (Synembryn): a novel conserved protein that is required for G(q)alpha signaling in the C. elegans nervous system.
abstract: Recent studies describe a network of signaling proteins centered around G(o)alpha and G(q)alpha that regulates neurotransmitter secretion in C. elegans by controlling the production and consumption of diacylglycerol (DAG). We sought other components of the Goalpha-G(q)alpha signaling network by screening for aldicarb-resistant mutants with phenotypes similar to egl-30 (G(q)alpha) mutants. In so doing, we identified ric-8, which encodes a novel protein named RIC-8 (synembryn). Through cDNA analysis, we show that RIC-8 is conserved in vertebrates. Through immunostaining, we show that RIC-8 is concentrated in the cytoplasm of neurons. Exogenous application of phorbol esters or loss of DGK-1 (diacylglycerol kinase) rescues ric-8 mutant phenotypes. A genetic analysis suggests that RIC-8 functions upstream of, or in conjunction with, EGL-30 (G(q)alpha).
authors.affiliation: Program in Molecular and Cell Biology, Oklahoma Medical Research Foundation, Oklahoma City 73104, USA.
authors.forename: K G
authors.initials: KG
authors.lastname: Miller
authors.forename: M D
authors.initials: MD
authors.lastname: Emerson
authors.forename: J R
authors.initials: JR
authors.lastname: McManus
authors.forename: J B
authors.initials: JB
authors.lastname: Rand
mesh_terms: D000375:Aging / Q000378:metabolism; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins; D017124:Conserved Sequence / Q000235:genetics; D019852:Diacylglycerol Kinase / Q000172:deficiency / Q000235:genetics; D005455:Fluorescent Antibody Technique; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D019204:GTP-Binding Proteins / Q000378:metabolism*; D020662:Guanine Nucleotide Exchange Factors; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009420:Nervous System / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D010641:Phenotype; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000502:physiology*; D009435:Synaptic Transmission / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D029742:Caenorhabditis elegans Proteins; D020662:Guanine Nucleotide Exchange Factors; D009687:Nuclear Proteins; C413418:RIC-8 protein, C elegans; C485884:Ric8a protein, mouse; D019852:Diacylglycerol Kinase; D019204:GTP-Binding Proteins; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D013755:Tetradecanoylphorbol Acetate