| 56506 |
Q9Z309 |
CIB2_MOUSE |
Calcium and integrin-binding family member 2 (Kinase-interacting protein 2) (KIP 2) |
DISRUPTION PHENOTYPE |
Causes profound hearing loss, whereas balance and retinal functions appear normal (PubMed:29255404, PubMed:29084757). Impaired stereocilia development in hair cells (PubMed:29255404). Abolished mechanoelectrical transduction (MET) currents in auditory hair cells; while unchanged in vestibular hair cells (PubMed:29255404). Hair bundle morphological abnormalities begin after birth, with regression of the stereocilia and rapid hair-cell death (PubMed:29084757). At P6-P7, the rounded horseshoe-shape bundles at the base of the cochlea lack their typical V-shape (PubMed:29084757). At P7, disorganization of stereocilia in outer hair cells (OHC), with fragmentation in some stereocilia bundles and stereocilia in the shortest row are heterogeneous in length (PubMed:29255404, PubMed:29084757). The inner hair cell (IHC) hair bundles at the cochlear base exhibit an abnormal wavy shape, but, unlike OHCs, all the stereocilia within the same row are of the same length (PubMed:29084757). At P8, the second row of OHC stereocilia are over-grown to the height close to the first row, whereas the third row are largely retracted, resulting in the loss of their staircase architecture (PubMed:29255404). In IHC, the kinocilium is not retracted properly at P8 (PubMed:29255404). On P9, most OHCs have discontinuous horseshoe-like shaped hair bundles, due to the loss of the centrally located stereocilia at the vertex of the bundle (PubMed:29084757). Many IHC bundles at this terminal mature stage still retain their kinocilia, whereas the wild-type IHCs loose this structure at post-hearing onset (beyond P14) stages (PubMed:29084757). On P18, the short row stereocilia have almost entirely disappeared in both IHC and OHC hair bundles, whereas those in the middle row are much shorter than usual, with some missing entirely (PubMed:29084757). At P20, apoptotic hair cells in the cochlea are detected (PubMed:29084757). At P30, disorganization of stereocilia is increased, with complete loss of stereocilia in some animals and other morphological abnormalities, such as stereocilia fusion (PubMed:29255404). On P90 and P120, only sporadic fused stereocilia or residual knoblike protrusions are observed on some of the remaining IHC stereociliary bundles of the mid-basal cochlea (PubMed:29084757). Near-complete loss of IHC and OHC bundles on P120 (PubMed:29084757). {ECO:0000269|PubMed:29084757, ECO:0000269|PubMed:29255404}. |