Mutations in a cyclic nucleotide-gated channel lead to abnormal thermosensation and chemosensation in C. elegans.
The C. elegans tax-4 mutants are abnormal in multiple sensory behaviors: they fail to respond to temperature or to water-soluble or volatile chemical attractants. We show that the predicted tax-4 gene product is highly homologous to vertebrate cyclic nucleotide-gated channels. Tax-4 protein expressed in cultured cells functions as a cyclic nucleotide-gated channel. The green fluorescent protein (GFP)-tagged functional Tax-4 protein is expressed in thermosensory, gustatory, and olfactory neurons mediating all the sensory behaviors affected by the tax-4 mutations. The Tax-4::GFP fusion is partly localized at the sensory endings of these neurons. The results suggest that a cyclic nucleotide-gated channel is required for thermosensation and chemosensation and that cGMP is an important intracellular messenger in C. elegans sensory transduction.
Komatsu
H
H
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
Mori
I
I
Rhee
J S
JS
Akaike
N
N
Ohshima
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D002417:Cattle; D002633:Chemotaxis; D006152:Cyclic GMP / Q000378:metabolism*; D004330:Drosophila; D029721:Drosophila Proteins; D017238:Genes, Helminth; D049452:Green Fluorescent Proteins; D006801:Humans; D007473:Ion Channels / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D008164:Luminescent Proteins / Q000096:biosynthesis; D046911:Macromolecular Substances; D008564:Membrane Potentials; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009475:Neurons, Afferent / Q000502:physiology*; D015221:Potassium Channels / Q000737:chemistry; D017433:Protein Structure, Secondary; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D015290:Second Messenger Systems; D017386:Sequence Homology, Amino Acid; D051637:Shaker Superfamily of Potassium Channels; D013696:Temperature
D029742:Caenorhabditis elegans Proteins; D029721:Drosophila Proteins; D007473:Ion Channels; D008164:Luminescent Proteins; D046911:Macromolecular Substances; D015221:Potassium Channels; D011993:Recombinant Fusion Proteins; C496929:Sh protein, Drosophila; D051637:Shaker Superfamily of Potassium Channels; C102184:tax-4 protein, C elegans; D049452:Green Fluorescent Proteins; D006152:Cyclic GMP