Involved in EGFR signaling. Interacts with RNF126. Associated with microtubules of the cytoskeleton and mitotic apparatus. Widely expressed. At 14.5 dpc, strong punctate expression in the otic mesenchyme. Detected in the cells lining the lumen of the primitive cochlear duct and in the nerve fibers of the spiral ganglion, as well as in the nerve fibers invading the cochlear epithelium. At 17.5 dpc, detected only in the mesenchyme around the cochlear duct. 2 days after birth (P2), the mesenchymal expression becomes weaker, except in the region of the spiral limbus, while expression is observed for the first time in the apical region of the developing pillar cells (PCs). Also observed in the cytoplasm of outer hair cells, in their innervating nerve fibers and in the marginal cells of stria vascularis. At P9 and P12, detected in the stria vascularis and strongly through the entire length of the inner and outer PCs. At these stages, in tissues of mesenchymal origin, restricted to the spiral limbus and the spiral ligament. At P14 and P16, strong expression is maintained in the PCs and in the marginal cells of the stria vascularis, weak expression in the spiral limbus and ligament. Also detected in Deiter's cells. At P19 and P22, intense expression in the PCs and stria vascularis, as well as in the cell bodies and processes of Deiter's cells. Weak expression in the spiral limbus and ligament. At P31, when the inner ear is functionally mature, expressed only in the PCs and stria vascularis. At P69, strong expression in the PCs and less intense in stria vascularis. In the vestibular maculae and the cristae ampullaris, expression similar to that observed in the cochlea: strong signal in the mesenchyme at the initial embryonic stages that progressively becomes weaker and is less prominent in the adult (P33). At 17.5 dpc and P2, observed in nerve fibers innervating the sensory epithelia. Expression in the vestibular epithelium starts at 17.5 dpc and is readily detected at P2. Later expression increases and persists in adult stages in which it is restricted to the apical cytoplasm of the epithelial cells (at protein level). Phosphorylated on tyrosine residues.