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Chemosensory organs as models of neuronal synapses

Abstract

Neuronal synapses are important microstructures that underlie complex cognitive capacities. Recent studies, primarily in Caenorhabditis elegans and Drosophila melanogaster, have revealed surprising parallels between these synapses and the 'chemosensory synapses' that reside at the tips of chemosensory cells that respond to environmental stimuli. Similarities in the structures, mechanisms of action and specific molecules found at these sites extend to the presynaptic, postsynaptic and glial entities composing both synapse types. In this article I propose that chemosensory synapses may serve as useful models of neuronal synapses, and consider the possibility that the two synapse types derive from a common ancestral structure.

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Figure 1: Similarities between sensory receptive endings and neuron–neuron synapses.
Figure 2: Neurotransmitter receptor-related proteins are expressed at sensory receptive endings.
Figure 3: C. elegans CEPsh glia envelop sensory and neuron–neuron synapses.

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Acknowledgements

I would like to thank J. Darnell, M. Heiman, M. Nedergaard and L. Vosshall for comments and discussions of the ideas presented here and R. Benton and Y. Lu for sharing images. This work was supported in part by US National Institutes of Health grant R01NS064273.

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Shaham, S. Chemosensory organs as models of neuronal synapses. Nat Rev Neurosci 11, 212–217 (2010). https://doi.org/10.1038/nrn2740

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