The Ca2+Channel Subunit β2 Regulates Ca2+Channel Abundance and Function in Inner Hair Cells and Is Required for Hearing

• DOI: 10.1523/jneurosci.1577-09.2009
• Publication Date: 2009-08-26T17:28:51Z
• Authors: Jakob Neef; Anna Gehrt; Anna V. Bulankina; Alexander C. Meyer; Dietmar Riedel; Ronald G. Gregg; Nicola Strenzke; Tobias Moser
• Keywords: Ribbon synapse

Hearing relies on Ca 2+ influx-triggered exocytosis in cochlear inner hair cells (IHCs). Here we studied the role of channel subunit V β 2 hearing. Of 1–4 mRNAs, IHCs predominantly contained . was severely impaired mice lacking extracardiac tissues ( −/− ). This involved deficits amplification and sound encoding. Otoacoustic emissions were reduced or absent mice, which showed strongly elevated auditory thresholds single neuron recordings brainstem response measurements. greatly (by 68%). mostly attributable to a decreased number membrane-standing 1.3 channels. Confocal imaging revealed presynaptic microdomains albeit with much lower amplitudes, indicating synaptic clustering fewer The coupling remaining influx IHC appeared unaffected. Extracellular sound-evoked spiking nucleus nerve spike rates mice. Still, sizable onset adapted found during suprathreshold stimulation indicated that residual encoding occurred, although channels one-third. normal developmental upregulation, clustering, gating large-conductance activated potassium absence Moreover, efferent innervation persist -deficient IHCs. In summary, has an essential regulating abundance properties and, thereby, is critical for development sound.