Immunolocalization of anion exchanger 2α in auditory sensory hair cells

• Published in: Hearing research 1997-08, Vol.110 (1), p.141-146
• Main Authors: Kalinec, Federico, Kalinec, Gilda, Negrini, Clelia, Kachar, Bechara
• Format: Article
• Language: English
• Subjects: Anion exchanger proteins; Auditory sensory transduction; Hair cells; Organ of Corti; Outer hair cells
• ISSN: 0378-5955; 1878-5891
• DOI: 10.1016/S0378-5955(97)00076-2

We have previously reported the isolation from a guinea pig organ of Corti cDNA library of a cDNA clone that encodes a novel isoform of the anion exchanger 2 (AE2) protein (Negrini, Rivolta, Kalinec and Kachar, 1995. Cloning of an organ of Corti anion exchanger 2 isoform with a truncated C-terminal domain. Biophys. Acta, 1236, 207–211). The deduced protein, named AE2α, has a conserved cytoplasmic domain and a short membrane domain with only two membrane spanning regions, as opposed to the fourteen present in the conventional AE2. Now, we are showing the immunolocalization and preliminary characterization of this protein using an antipeptide antibody specific for this novel AE2 isoform. In Western blots, this antibody binds to an ∼89 kDa polypeptide that corresponds to a phosphorylated protein with serines as main phosphate acceptor residues. In immunofluorescence experiments, the antibody labels the stereocilia and the lateral wall of the outer hair cells and the stereocilia of the inner hair cells. Our results suggest that AE2α is a membrane-cytoskeletal linker in regions of the hair cell, where sensory transduction mechanisms take place.