title: Anion exchanger 1b in stereocilia is required for the functioning of mechanotransducer channels in lateral-line hair cells of zebrafish.
abstract: The anion exchanger (AE) plays critical roles in physiological processes including CO2 transport and volume regulation in erythrocytes and acid-base regulation in renal tubules. Although expression of the AE in inner-ear hair cells was reported, its specific localization and function are still unclear. Using in situ hybridization, we found that the AE1b transcript is expressed in lateral-line hair cells of zebrafish larvae. An immunohistochemical analysis with a zebrafish-specific antibody localized AE1b to stereocilia of hair cells, and the expression was eliminated by morpholino knockdown of AE1b. A non-invasive, scanning ion-selective electrode technique was applied to analyze mechanotransducer (MET) channel-mediated Ca2+ influx at stereocilia of hair cells of intact fish. Ca2+ influx was effectively suppressed by AE1b morpholino knockdown and inhibitor (DIDS) treatment. Elevating external Ca2+ (0.2 to 2 mM) neutralized the inhibition of DIDS. Taken together, this study provides solid evidence to show that AE1b in stereocilia is required for the proper functioning of MET channels.
authors: Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan, ROC.
authors: Yuan-Hsiang
authors: YH
authors: Lin
authors: Department of Pediatrics, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Pediatrics, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.
authors: Giun-Yi
authors: GY
authors: Hung
authors: Department of Life Science, National Taiwan Normal University, Taipei, Taiwan, ROC.
authors: Liang-Chun
authors: LC
authors: Wu
authors: Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, ROC.
authors: Sheng-Wen
authors: SW
authors: Chen
authors: Department of Life Science, National Taiwan Normal University, Taipei, Taiwan, ROC.
authors: Li-Yih
authors: LY
authors: Lin
authors: Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, ROC.
authors: Jiun-Lin
authors: JL
authors: Horng
mesh_terms: D000818:Animals; D001457:Anion Exchange Protein 1, Erythrocyte / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D055785:Gene Knockdown Techniques; D008465:Mechanoreceptors / Q000378:metabolism*; D040542:Mechanotransduction, Cellular; D021381:Protein Transport; D059547:Stereocilia / Q000378:metabolism*; D015027:Zebrafish / Q000502:physiology*
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D002118:Calcium