| First Author | Defourny J | Year | 2013 |
| Journal | Nat Commun | Volume | 4 |
| Pages | 1438 | PubMed ID | 23385583 |
| Mgi Jnum | J:226226 | Mgi Id | MGI:5696506 |
| Doi | 10.1038/ncomms2445 | Citation | Defourny J, et al. (2013) Ephrin-A5/EphA4 signalling controls specific afferent targeting to cochlear hair cells. Nat Commun 4:1438 |
| abstractText | Hearing requires an optimal afferent innervation of sensory hair cells by spiral ganglion neurons in the cochlea. Here we report that complementary expression of ephrin-A5 in hair cells and EphA4 receptor among spiral ganglion neuron populations controls the targeting of type I and type II afferent fibres to inner and outer hair cells, respectively. In the absence of ephrin-A5 or EphA4 forward signalling, a subset of type I projections aberrantly overshoot the inner hair cell layer and invade the outer hair cell area. Lack of type I afferent synapses impairs neurotransmission from inner hair cells to the auditory nerve. By contrast, radial shift of type I projections coincides with a gain of presynaptic ribbons that could enhance the afferent signalling from outer hair cells. Ephexin-1, cofilin and myosin light chain kinase act downstream of EphA4 to induce type I spiral ganglion neuron growth cone collapse. Our findings constitute the first identification of an Eph/ephrin-mediated mutual repulsion mechanism responsible for specific sorting of auditory projections in the cochlea. |
