Abstract
Signal transduction through heterotrimeric G proteins is critical for sensory response across species. Regulator of G protein signaling (RGS) proteins are negative regulators of signal transduction. Herein we describe a role for C. elegans RGS-3 in the regulation of sensory behaviors. rgs-3 mutant animals fail to respond to intense sensory stimuli but respond normally to low concentrations of specific odorants. We find that loss of RGS-3 leads to aberrantly increased G protein-coupled calcium signaling but decreased synaptic output, ultimately leading to behavioral defects. Thus, rgs-3 responses are restored by decreasing G protein-coupled signal transduction, either genetically or by exogenous dopamine, by expressing a calcium-binding protein to buffer calcium levels in sensory neurons or by enhancing glutamatergic synaptic transmission from sensory neurons. Therefore, while RGS proteins generally act to downregulate signaling, loss of a specific RGS protein in sensory neurons can lead to defective responses to external stimuli.
Publication types
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Research Support, N.I.H., Extramural
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Research Support, Non-U.S. Gov't
MeSH terms
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Animals
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Caenorhabditis elegans / genetics
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Caenorhabditis elegans / metabolism*
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Caenorhabditis elegans / ultrastructure
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Caenorhabditis elegans Proteins / genetics
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Caenorhabditis elegans Proteins / metabolism*
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Calcium / metabolism
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Calcium Signaling / physiology
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GTP-Binding Proteins / genetics
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GTP-Binding Proteins / metabolism
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GTPase-Activating Proteins / genetics
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GTPase-Activating Proteins / metabolism
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Glutamic Acid / metabolism
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Mutation / genetics
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Nervous System / metabolism*
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Nervous System / ultrastructure
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RGS Proteins / genetics
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RGS Proteins / metabolism*
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Receptors, G-Protein-Coupled / metabolism*
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Sensation / physiology*
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Signal Transduction / physiology
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Smell / physiology
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Synapses / metabolism
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Synaptic Transmission / physiology
Substances
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Caenorhabditis elegans Proteins
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GTPase-Activating Proteins
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RGS Proteins
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RGS-3 protein, C elegans
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Receptors, G-Protein-Coupled
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Rgs3 protein, mouse
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Glutamic Acid
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GTP-Binding Proteins
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Calcium