OSM-9, a novel protein with structural similarity to channels, is required for olfaction, mechanosensation, and olfactory adaptation in Caenorhabditis elegans.
Although cyclic nucleotide-gated channels mediate sensory transduction in olfaction and vision, other forms of sensory transduction are independent of these channels. Caenorhabditis elegans cyclic nucleotide-gated channel mutants respond normally to some olfactory stimuli and to osmotic stimuli, suggesting that these chemosensory responses use an alternative sensory transduction pathway. One gene that may act in this pathway is osm-9, which is required for each of these responses as well as a mechanosensory response to nose touch. osm-9 encodes a protein with ankyrin repeats and multiple predicted transmembrane domains that has limited similarity to the Drosophila phototransduction channels transient receptor potential (TRP) and TRP-like (TRPL). The sequence of OSM-9 and other TRP-like genes reveals a previously unsuspected diversity of mammalian and invertebrate genes in this family. osm-9 is required for the activity of the predicted G-protein-coupled odorant receptor ODR-10, which acts in the AWA olfactory neurons; its similarity to other G-protein-regulated transduction channels suggests that OSM-9 is involved in AWA signaling. osm-9:: GFP fusion genes are expressed in a subset of chemosensory, mechanosensory, and osmosensory neurons. osm-9 also affects olfactory adaptation within neurons that require the cyclic nucleotide-gated channel for olfaction; in these neurons, the gene has a regulatory function and not a primary role in sensory transduction.
Colbert
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Howard Hughes Medical Institute, Programs in Developmental Biology, Neuroscience, and Genetics, Department of Anatomy, The University of California, San Francisco, California 94143-0452, USA.
Smith
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TL
Bargmann
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D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000235:genetics / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D002148:Calmodulin-Binding Proteins / Q000737:chemistry; D003001:Cloning, Molecular; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics; D019204:GTP-Binding Proteins / Q000502:physiology; D005786:Gene Expression Regulation; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D007473:Ion Channels / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D008465:Mechanoreceptors / Q000502:physiology*; D008565:Membrane Proteins / Q000737:chemistry; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D009475:Neurons, Afferent / Q000378:metabolism*; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*; D012903:Smell / Q000235:genetics / Q000502:physiology*; D013045:Species Specificity; D013329:Structure-Activity Relationship; D050916:TRPV Cation Channels; D014110:Touch / Q000235:genetics / Q000502:physiology*; D050051:Transient Receptor Potential Channels
D029742:Caenorhabditis elegans Proteins; D002148:Calmodulin-Binding Proteins; D029721:Drosophila Proteins; D015801:Helminth Proteins; D007473:Ion Channels; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C108820:OSM-9 protein, C elegans; D011993:Recombinant Fusion Proteins; D050916:TRPV Cation Channels; D050051:Transient Receptor Potential Channels; C074192:trpl protein, Drosophila; D019204:GTP-Binding Proteins