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Cochlear ribbon synapse maturation requires Nlgn1 and Nlgn3.

ABSTRACT: Hearing depends on precise synaptic transmission between cochlear inner hair cells and spiral ganglion neurons through afferent ribbon synapses. Neuroligins (Nlgns) facilitate synapse maturation in the brain, but they have gone unstudied in the cochlea. We report Nlgn3 and Nlgn1 knockout (KO) cochleae have fewer ribbon synapses and have impaired hearing. Nlgn3 KO is more vulnerable to noise trauma with limited activity at high frequencies one day after noise. Furthermore, Nlgn3 KO cochleae have a 5-fold reduction in synapse number compared to wild type after two weeks of recovery. Double KO cochlear phenotypes are more prominent than the KOs, for example, 5-fold smaller synapses, 25% reduction in synapse density, and 30% less synaptic output. These observations indicate Nlgn3 and Nlgn1 are essential to cochlear ribbon synapse maturation and function.

SUBMITTER: Ramirez MA

PROVIDER: S-EPMC9386149 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Cochlear ribbon synapse maturation requires Nlgn1 and Nlgn3.

Ramirez Miguel A MA Ninoyu Yuzuru Y Miller Cayla C Andrade Leonardo R LR Edassery Seby S Bomba-Warczak Ewa E Ortega Briana B Manor Uri U Rutherford Mark A MA Friedman Rick A RA Savas Jeffrey N JN

iScience 20220720 8

Hearing depends on precise synaptic transmission between cochlear inner hair cells and spiral ganglion neurons through afferent ribbon synapses. Neuroligins (Nlgns) facilitate synapse maturation in the brain, but they have gone unstudied in the cochlea. We report Nlgn3 and Nlgn1 knockout (KO) cochleae have fewer ribbon synapses and have impaired hearing. Nlgn3 KO is more vulnerable to noise trauma with limited activity at high frequencies one day after noise. Furthermore, <i ...[more]

PMID: 35992071

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