5f3x

Structural highlights

Disease

[USH1C_HUMAN] Defects in USH1C are the cause of Usher syndrome type 1C (USH1C) [MIM:276904]; also known as Usher syndrome type I Acadian variety. USH is a genetically heterogeneous condition characterized by the association of retinitis pigmentosa and sensorineural deafness. Age at onset and differences in auditory and vestibular function distinguish Usher syndrome type 1 (USH1), Usher syndrome type 2 (USH2) and Usher syndrome type 3 (USH3). USH1 is characterized by profound congenital sensorineural deafness, absent vestibular function and prepubertal onset of progressive retinitis pigmentosa leading to blindness.^[1] Defects in USH1C are the cause of deafness, autosomal recessive, 18A (DFNB18A) [MIM:602092]. A form of sensorineural hearing loss. Sensorineural deafness results from damage to the neural receptors of the inner ear, the nerve pathways to the brain, or the area of the brain that receives sound information.^[2]

Function

[USH1C_HUMAN] Required for normal development and maintenance of cochlear hair cell bundles. Anchoring/scaffolding protein that is a part of the functional network formed by USH1C, USH1G, CDH23 and MYO7A that mediates mechanotransduction in cochlear hair cells. Required for normal hearing (By similarity). [ANS4B_MOUSE] As part of the intermicrovillar adhesion complex/IMAC plays a role in epithelial brush border differentiation, controlling microvilli organization and length. Plays a role in assembly of the complex (By similarity). May play a role in cellular response to endoplasmic reticulum stress (PubMed:22589549).[UniProtKB:Q8N8V4]^[3]

See Also

• Harmonin

References

1. ↑ Verpy E, Leibovici M, Zwaenepoel I, Liu XZ, Gal A, Salem N, Mansour A, Blanchard S, Kobayashi I, Keats BJ, Slim R, Petit C. A defect in harmonin, a PDZ domain-containing protein expressed in the inner ear sensory hair cells, underlies Usher syndrome type 1C. Nat Genet. 2000 Sep;26(1):51-5. PMID:10973247 doi:10.1038/79171
2. ↑ Ahmed ZM, Smith TN, Riazuddin S, Makishima T, Ghosh M, Bokhari S, Menon PS, Deshmukh D, Griffith AJ, Riazuddin S, Friedman TB, Wilcox ER. Nonsyndromic recessive deafness DFNB18 and Usher syndrome type IC are allelic mutations of USHIC. Hum Genet. 2002 Jun;110(6):527-31. Epub 2002 May 3. PMID:12107438 doi:10.1007/s00439-002-0732-4
3. ↑ Sato Y, Hatta M, Karim MF, Sawa T, Wei FY, Sato S, Magnuson MA, Gonzalez FJ, Tomizawa K, Akaike T, Yoshizawa T, Yamagata K. Anks4b, a novel target of HNF4alpha protein, interacts with GRP78 protein and regulates endoplasmic reticulum stress-induced apoptosis in pancreatic beta-cells. J Biol Chem. 2012 Jun 29;287(27):23236-45. doi: 10.1074/jbc.M112.368779. Epub, 2012 May 15. PMID:22589549 doi:http://dx.doi.org/10.1074/jbc.M112.368779
4. ↑ Li J, He Y, Lu Q, Zhang M. Mechanistic Basis of Organization of the Harmonin/USH1C-Mediated Brush Border Microvilli Tip-Link Complex. Dev Cell. 2016 Jan 25;36(2):179-89. doi: 10.1016/j.devcel.2015.12.020. PMID:26812017 doi:http://dx.doi.org/10.1016/j.devcel.2015.12.020