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.
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
H
H
Komatsu
I
I
Mori
J S
JS
Rhee
N
N
Akaike
Y
Y
Ohshima
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