At 17.5 dpc, primarily detected in the spiral prominence and the Claudius cells and weakly in hair cells (at protein level). Also detected in the lumen surface of interdental cells in the proximity of Reissner's membrane and at the base of nascent tectorial membrane (at protein level). Similar expression pattern in P0 cochlea, with additional detection in some supporting cells (at protein level). At the same stage, in saccule, weakly expressed in hair cells and more prominently in the saccular roof (at protein level). By P6, expression becomes more restricted. Mainly detected in the outer hair cells, Deiter's cells and Claudius cells (at protein level). In the tectorial membrane, localized to the base. In the saccule, detected at high levels in the saccule roof with little change in the hair cells (at protein level). Belongs to the otogelin family.