USH2A

This gene encodes a protein that contains laminin EGF motifs, a pentaxin domain, and many fibronectin type III motifs. The protein is found in the basement membrane, and may be important in development and homeostasis of the inner ear and retina. Mutations within this gene have been associated with Usher syndrome type IIa and retinitis pigmentosa. Multiple transcript variants encoding different isoforms have been found for this gene.

Full Name

usherin

Function

Involved in hearing and vision as member of the USH2 complex. In the inner ear, required for the maintenance of the hair bundle ankle formation, which connects growing stereocilia in developing cochlear hair cells. In retina photoreceptors, the USH2 complex is required for the maintenance of periciliary membrane complex that seems to play a role in regulating intracellular protein transport.

Biological Process

Biological Process animal organ morphogenesis Source:GO_Central1 Publication
Biological Process cell migration Source:GO_Central1 Publication
Biological Process establishment of localization in cell Source:Ensembl
Biological Process establishment of protein localization Source:UniProtKB
Biological Process hair cell differentiation Source:BHF-UCL
Biological Process inner ear auditory receptor cell differentiation Source:Ensembl
Biological Process inner ear receptor cell differentiation Source:BHF-UCL
Biological Process maintenance of animal organ identity Source:HGNC-UCL1 Publication
Biological Process photoreceptor cell maintenance Source:HGNC-UCL1 Publication
Biological Process response to stimulus Source:UniProtKB-KW
Biological Process sensory perception of light stimulus Source:HGNC-UCL1 Publication
Biological Process sensory perception of sound Source:HGNC-UCL1 Publication
Biological Process substrate adhesion-dependent cell spreading Source:GO_Central1 Publication
Biological Process tissue development Source:GO_Central1 Publication
Biological Process visual perception Source:UniProtKB-KW

Cellular Location

Cell projection, stereocilium membrane
Component of the interstereocilia ankle links in the inner ear sensory cells. In photoreceptors, localizes at a plasma membrane microdomain in the apical inner segment that surrounds the connecting cilia called periciliary membrane complex.
Isoform 2
Secreted

Involvement in disease

Usher syndrome 2A (USH2A):
USH is a genetically heterogeneous condition characterized by the association of retinitis pigmentosa with 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). USH2 is characterized by congenital mild hearing impairment with normal vestibular responses.
Retinitis pigmentosa 39 (RP39):
A retinal dystrophy belonging to the group of pigmentary retinopathies. Retinitis pigmentosa is characterized by retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well.

Topology

Extracellular: 32-5042
Helical: 5043-5063
Cytoplasmic: 5064-5202