Required for proper hearing, plays a role in maintaining the integrity of the tectorial membrane. Homooligomer; can for homodimers and homotetramers (PubMed:21368133, PubMed:25589040). Interacts with TECTA and TECTB (PubMed:21368133). Localizes to the tip of cochlear outer hair cells and to the tectorial membrane. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the immunoglobulin superfamily. CEA family.