ESPN

This gene encodes a multifunctional actin-bundling protein. It plays a major role in regulating the organization, dimensions, dynamics, and signaling capacities of the actin filament-rich, microvillus-type specializations that mediate sensory transduction in various mechanosensory and chemosensory cells. Mutations in this gene are associated with autosomal recessive neurosensory deafness, and autosomal dominant sensorineural deafness without vestibular involvement. [provided by RefSeq, Nov 2009]

Espin

Multifunctional actin-bundling protein. Plays a major role in regulating the organization, dimension, dynamics and signaling capacities of the actin filament-rich microvilli in the mechanosensory and chemosensory cells (PubMed:29572253).

Required for the assembly and stabilization of the stereociliary parallel actin bundles. Plays a crucial role in the formation and maintenance of inner ear hair cell stereocilia (By similarity).

Involved in the elongation of actin in stereocilia (PubMed:29572253).

In extrastriolar hair cells, required for targeting MYO3B to stereocilia tips, and for regulation of stereocilia diameter and staircase formation.

Actin filament bundle assembly Source: GO_Central
Microvillar actin bundle assembly Source: UniProtKB
Sensory perception of sound Source: UniProtKB-KW

Cytoskeleton; Stereocilium; Microvillus

Deafness, autosomal recessive, 36, with or without vestibular involvement (DFNB36):
A form of non-syndromic 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. DFNB36 is characterized by prelingual, profound hearing loss, and vestibular areflexia in some patients.
Usher syndrome 1M (USH1M):
A form of Usher syndrome, 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). USH1M is an autosomal recessive disease characterized by prelingual sensorineural hearing loss, vestibular dysfunction, night blindness, and progressive impairment of vision.