Cochlin

---

title: "Cochlin" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["extracellular-matrix-proteins"] description: "Protein highly abundant in the cochlea and vestibule of the inner ear" topic_path: "general/extracellular-matrix-proteins" source: "https://en.wikipedia.org/wiki/Cochlin" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Protein highly abundant in the cochlea and vestibule of the inner ear ::

Cochlin is a protein that in humans is encoded by the COCH gene. It is an extracellular matrix (ECM) protein highly abundant in the cochlea and vestibule of the inner ear, constituting the major non-collagen component of the ECM of the inner ear. The protein is highly conserved in human, mouse, and chicken, showing 94% and 79% amino acid identity of human to mouse and chicken sequences, respectively.

Structure

Cochlin contains three protein domains: an N-terminal LCCL domain, and two copies of Von Willebrand factor type A domains.

Function

The gene is expressed in spindle-shaped cells located along nerve fibers between the auditory ganglion and sensory epithelium. These cells accompany neurites at the habenula perforata, the opening through which neurites extend to innervate hair cells. This and the pattern of expression of this gene in chicken inner ear paralleled the histologic findings of acidophilic deposits, consistent with mucopolysaccharide ground substance, in temporal bones from DFNA9 (autosomal dominant nonsyndromic sensorineural deafness 9) patients. Mutations that cause DFNA9 have been reported in this gene.

Cochlin has been identified in the trabecular meshwork (TM) of glaucoma patients, but not in healthy controls. The TM is a filter like area of tissue in the eye; cochlin may have a role in cell adhesion, mechanosensation, and modulation of the TM filter.

It is also expressed in follicular dendritic cells in spleen and lymph nodes. Here, cochlin is cleaved by aggrecanases and secreted into blood circulation during inflammation, contributing to the antibacterial innate immune response.

References

References

1. (November 1998). "Mutations in a novel cochlear gene cause DFNA9, a human nonsyndromic deafness with vestibular dysfunction". Nature Genetics.
2. "Entrez Gene: COCH coagulation factor C homolog, cochlin (Limulus polyphemus)".
3. (December 1997). "Mapping and characterization of a novel cochlear gene in human and in mouse: a positional candidate gene for a deafness disorder, DFNA9". Genomics.
4. (March 2001). "Identification of the protein product of the Coch gene (hereditary deafness gene) as the major component of bovine inner ear protein". Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease.
5. "Cochlin (O43405)".
6. (2011). "Cochlin induced TREK-1 co-expression and annexin A2 secretion: role in trabecular meshwork cell elongation and motility". PLOS ONE.
7. (September 2007). "Cochlin in the eye: functional implications". Progress in Retinal and Eye Research.
8. (May 2013). "Cochlin produced by follicular dendritic cells promotes antibacterial innate immunity". Immunity.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::