title: Rho participates in chemoreceptor-induced changes in morphology to hair bundle mechanoreceptors of the sea anemone, Nematostella vectensis.
abstract: Adjustable hair bundle mechanoreceptors located on anemone tentacles detect movements of nearby, swimming prey. The hair bundles are formed by numerous actin-based stereocilia that converge onto a single, central kinocilium. Interestingly, morphological and functional changes to the hair bundles are induced by activating chemoreceptors that bind prey-derived N-acetylated sugars and proline, respectively. Morphological changes to the hair bundles involve alterations to the actin cytoskeleton of stereocilia. A pharmacological activation of Rho induces hair bundles to elongate to lengths comparable to those normally induced by exposure to N-acetylneuraminic acid (NANA) and prevents shortening of hair bundles normally induced by proline. Rho inhibition prevents NANA-induced elongation, but does not prevent proline-induced shortening of hair bundles. Western blots feature a band similar in mass to that predicted for a Rho homolog in the genome of Nematostella. Immunocytochemistry localizes Rho in stereocilia of the hair bundle. Anemone hair bundles arise from multicellular complexes. Data from experiments using heptanol, a gap junction uncoupler, indicate that cell-cell communication is required in order for activated chemoreceptors to induce morphological changes to the hair bundles.
authors.affiliation: Department of Biology, University of Louisiana, Lafayette, LA 70504, USA. amk4653@louisiana.edu
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Allaire
authors.forename: Glen M
authors.initials: GM
authors.lastname: Watson
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D000001:Calcimycin / Q000494:pharmacology; D061207:Calcium Ionophores / Q000494:pharmacology; D002450:Cell Communication / Q000187:drug effects / Q000502:physiology; D002628:Chemoreceptor Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism; D017629:Gap Junctions / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D019850:Heptanol / Q000494:pharmacology; D007150:Immunohistochemistry; D008465:Mechanoreceptors / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D008954:Models, Biological; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000494:pharmacology; D012615:Sea Anemones / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects; D020741:rho GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D061207:Calcium Ionophores; D000001:Calcimycin; D019850:Heptanol; D020741:rho GTP-Binding Proteins; D019158:N-Acetylneuraminic Acid