posted on 2023-06-09, 15:24authored byLaura F Corns, Stuart L Johnson, Terri Roberts, Kishani M Ranatunga, Aenea Hendry, Federico Ceriani, Saaid Safieddine, Karen P Steel, Andy Forge, Christine Petit, David N Furness, Corne Kros, Walter Marcotti
In the adult auditory organ, mechanoelectrical transducer (MET) channels are essential for transducing acoustic stimuli into electrical signals. In the absence of incoming sound, a fraction of the MET channels on top of the sensory hair cells are open, resulting in a sustained depolarizing current. By genetically manipulating the in vivo expression of molecular components of the MET apparatus, we show that during pre-hearing stages the MET current is essential for establishing the electrophysiological properties of mature inner hair cells (IHCs). If the MET current is abolished in adult IHCs, they revert into cells showing electrical and morphological features characteristic of pre-hearing IHCs, including the re-establishment of cholinergic efferent innervation. The MET current is thus critical for the maintenance of the functional properties of adult IHCs, implying a degree of plasticity in the mature auditory system in response to the absence of normal transduction of acoustic signals.
Funding
Functional significance of developmental aquisition of positional gradients on normal and mutant mamalian hair cells; RXK5; MRC-Medical Research Council; G0100798
Mechanisms of aminoglyscoside ototoxicity and drug damage repair in sensory hair cells: towards the design of otoprotective strategies.; G1025; MRC-MEDICAL RESEARCH COUNCIL; MR/K005561/1