title: Restrictive expression of acid-sensing ion channel 5 (asic5) in unipolar brush cells of the vestibulocerebellum.
abstract: Acid-sensing ion channels (Asic) are ligand-gated ion channels in the Degenerin/Epithelial Na+ channel (Deg/ENaC) family. Asic proteins are richly expressed in mammalian neurons. Mammals express five Asic genes: Asic1-5. The gene product of Asic5 is an orphan member of the family about which little is known. To investigate Asic5 expression, we created an Asic5 reporter mouse. We find that Asic5 is chiefly expressed in the brain in the cerebellum, specifically in the ventral uvula and nodulus of the vestibulocerebellum. Here, Asic5 is restrictively expressed in a subset of interneurons in the granular layer. The locale, distinctive shape and immunohistochemical properties of these Asic5-expressing interneurons identify them as unipolar brush cells (UBC). Asic5 is richly expressed in a subset of UBCs that also express the metabotropic glutamate receptor 1α (mGluR1α) but not those that express calretinin. Results from single cell RT-PCR and electrophysiological examination of these cells are consistent with this identity. Such observations are consistent with Asic5 playing a key role in the physiology of UBCs and in the function of the vestibulocerebellum.
authors.affiliation: Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America.
authors.forename: Nina
authors.initials: N
authors.lastname: Boiko
authors.affiliation: Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America.
authors.forename: Volodymyr
authors.initials: V
authors.lastname: Kucher
authors.affiliation: Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America.
authors.forename: James D
authors.initials: JD
authors.lastname: Stockand
mesh_terms: D062565:Acid Sensing Ion Channels / Q000235:genetics*; D000818:Animals; D016764:Cell Polarity; D002531:Cerebellum / Q000166:cytology* / Q000502:physiology; D055724:Electrophysiological Phenomena; D005786:Gene Expression Regulation; D007395:Interneurons / Q000378:metabolism; D051379:Mice; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism
chemical_list: D062565:Acid Sensing Ion Channels; C000594476:Asic5 protein, mouse; D018094:Receptors, Metabotropic Glutamate; C104077:metabotropic glutamate receptor type 1