title: In vivo imaging of C. elegans mechanosensory neurons demonstrates a specific role for the MEC-4 channel in the process of gentle touch sensation.
abstract: In the nematode C. elegans, genes encoding components of a putative mechanotransducing channel complex have been identified in screens for light-touch-insensitive mutants. A long-standing question, however, is whether identified MEC proteins act directly in touch transduction or contribute indirectly by maintaining basic mechanoreceptor neuron physiology. In this study, we used the genetically encoded calcium indicator cameleon to record cellular responses of mechanosensory neurons to touch stimuli in intact, behaving nematodes. We defined a gentle touch sensory modality that adapts with a time course of approximately 500 ms and primarily senses motion rather than pressure. The DEG/ENaC channel subunit MEC-4 and channel-associated stomatin MEC-2 are specifically required for neural responses to gentle mechanical stimulation, but do not affect the basic physiology of touch neurons or their in vivo responses to harsh mechanical stimulation. These results distinguish a specific role for the MEC channel proteins in the process of gentle touch mechanosensation.
authors.affiliation: Division of Biology, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suzuki
authors.forename: Rex
authors.initials: R
authors.lastname: Kerr
authors.forename: Laura
authors.initials: L
authors.lastname: Bianchi
authors.forename: Christian
authors.initials: C
authors.lastname: Frøkjaer-Jensen
authors.forename: Dan
authors.initials: D
authors.lastname: Slone
authors.forename: Jian
authors.initials: J
authors.lastname: Xue
authors.forename: Beate
authors.initials: B
authors.lastname: Gerstbrein
authors.forename: Monica
authors.initials: M
authors.lastname: Driscoll
authors.forename: William R
authors.initials: WR
authors.lastname: Schafer
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology*; D020746:Calcium Channels, L-Type / Q000502:physiology; D002478:Cells, Cultured; D008465:Mechanoreceptors / Q000502:physiology*; D040542:Mechanotransduction, Cellular / Q000235:genetics / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D014110:Touch / Q000235:genetics / Q000502:physiology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D020746:Calcium Channels, L-Type; C115871:Mec-4 protein, C elegans; D008565:Membrane Proteins