Otoferlin Couples to Clathrin-Mediated Endocytosis in Mature Cochlear Inner Hair Cells

• DOI: 10.1523/jneurosci.5689-12.2013
• Publication Date: 2013-05-29T16:28:54Z
• Authors: Susanne V. Duncker; Christoph Franz; Stephanie Kuhn; Uwe Schulte; Dario Campanelli; Niels Brandt; Bernhard Hirt; Bernd Fakler; Nikolaus Blin; Peter Ruth; Jutta Engel; Walter Marcotti; Ulrike Zimmermann; Marlies Knipper
• Keywords: Ribbon synapse; Colocalization

The encoding of auditory information with indefatigable precision requires efficient resupply vesicles at inner hair cell (IHC) ribbon synapses. Otoferlin, a transmembrane protein responsible for deafness in DFNB9 families, has been postulated to act as calcium sensor exocytosis well be involved rapid vesicle replenishment IHCs. However, the molecular basis recycling IHCs is largely unknown. In present study, we used high-resolution liquid chromatography coupled mass spectrometry copurify otoferlin interaction partners mammalian cochlea. We identified multiple subunits adaptor complex AP-2 (CLAP), an essential component clathrin-mediated endocytosis, binding rats and mice. between was confirmed by coimmunoprecipitation. also found that interacts myosin VI, another partner important endocytosis (CME). expression verified reverse transcription PCR. Confocal microscopy experiments revealed its colocalization confined mature When CME inhibited blocking dynamin action, real-time changes membrane capacitance showed impaired synaptic but not immature suggest otoferlin-AP-2 drives Ca 2+ - stimulus-dependent compensating