title: Expression and vesicular localization of mouse Trpml3 in stria vascularis, hair cells, and vomeronasal and olfactory receptor neurons.
abstract: TRPML3 is a member of the mucolipin branch of the transient receptor potential cation channel family. A dominant missense mutation in Trpml3 (also known as Mcoln3) causes deafness and vestibular impairment characterized by stereocilia disorganization, hair cell loss, and endocochlear potential reduction. Both marginal cells of the stria vascularis and hair cells express Trpml3 mRNA. Here we used in situ hybridization, quantitative RT-qPCR, and immunohistochemistry with several antisera raised against TRPML3 to determine the expression and subcellular distribution of TRPML3 in the inner ear as well as in other sensory organs. We also use Trpml3 knockout tissues to distinguish TRPML3-specific from nonspecific immunoreactivities. We find that TRPML3 localizes to vesicles of hair cells and strial marginal cells but not to stereociliary ankle links or pillar cells, which nonspecifically react with two antisera raised against TRPML3. Upon cochlear maturation, TRPML3 protein is redistributed to perinuclear vesicles of strial marginal cells and is augmented in inner hair cells vs. outer hair cells. Mouse somatosensory neurons, retinal neurons, and taste receptor cells do not appear to express physiologically relevant levels of TRPML3. Finally, we found that vomeronasal and olfactory sensory receptor cells do express TRPML3 mRNA and protein, which localizes to vesicles in their somas and dendrites as well as at apical dendritic knobs.
authors.affiliation: Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Castiglioni
authors.affiliation: Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.|Integrated Graduate Program in the Life Sciences (IGP), Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.
authors.forename: Natalie N
authors.initials: NN
authors.lastname: Remis
authors.affiliation: Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.|Northwestern University Interdepartmental Neuroscience (NUIN) Graduate Program, Chicago, Illinois 60611.
authors.forename: Emma N
authors.initials: EN
authors.lastname: Flores
authors.affiliation: Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.|Integrated Graduate Program in the Life Sciences (IGP), Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.|Northwestern University Interdepartmental Neuroscience (NUIN) Graduate Program, Chicago, Illinois 60611.|Departments of Neurology and Physiology, and Hugh Knowles Center for Clinical and Basic Science in Hearing and Its Disorders, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.
authors.forename: Jaime
authors.initials: J
authors.lastname: García-Añoveros
mesh_terms: D000818:Animals; D057809:HEK293 Cells; D006198:Hair Cells, Auditory / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D051907:Lysosomal Membrane Proteins / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018034:Olfactory Receptor Neurons / Q000166:cytology / Q000378:metabolism*; D012160:Retina / Q000166:cytology / Q000378:metabolism; D013316:Stria Vascularis / Q000166:cytology / Q000378:metabolism*; D050053:TRPM Cation Channels / Q000235:genetics / Q000378:metabolism*; D013650:Taste Buds / Q000166:cytology / Q000378:metabolism; D050051:Transient Receptor Potential Channels; D019147:Vomeronasal Organ / Q000166:cytology* / Q000378:metabolism; D052118:Lysosomal-Associated Membrane Protein 1
chemical_list: D051907:Lysosomal Membrane Proteins; D050053:TRPM Cation Channels; D050051:Transient Receptor Potential Channels; C052255:Lamp1 protein, mouse; D052118:Lysosomal-Associated Membrane Protein 1; C470193:Mcoln3 protein, mouse