solute carrier family 26 member 5 (SLC26A5, prestin, PRES)

Function: - motor protein - converts auditory stimuli to length changes in outer hair cells - mediates sound amplification in mammalian hearing organ - prestin is a bidirectional voltage-to-force converter; it can operate at microsecond rates - uses cytoplasmic anions as extrinsic voltage sensors, probably chloride & bicarbonate - after binding to a site with millimolar affinity, these anions are translocated across the membrane in response to changes in transmembrane voltage - they move towards the extracellular surface following hyperpolarization, & towards the cytoplasmic side in response to depolarization - anion translocation triggers conformational changes in prestin that ultimately alter its surface area in the plane of the plasma membrane - the area decreases when the anion is near the cytoplasmic face of the membrane (short state), & increases when the anion has crossed the membrane to the outer surface (long state) - thus prestin acts as an incomplete transporter; it swings anions across the plasma membrane, but does not allow these anions to dissociate & escape to the extracellular space Structure: - belongs to the SLC26A/sulP transporter (TC 2.A.53) family - contains 1 STAS domain Compartment: - cell membrane - lateral wall of outer hair cells Alternative splicing: named isoforms=4 Pathology: - defects in SLC26A5 are a cause of some forms of recessive non-syndromic deafness Pharmacology: - salicylate, an inhibitor of outer hair cell motility, acts as competitive antagonist at the prestin anion-binding site (putative)

General

glycoprotein solute carrier family 26 (SLC26, SLC26A) transmembrane 12 protein

Properties

SIZE: MW = 81 kD entity length = 744 aa COMPARTMENT: cellular membrane MOTIF: cytoplasmic domain {1-79} transmembrane domain {80-100} exoplasmic loop {101-102} transmembrane domain {103-123} cytoplasmic loop {124-131} transmembrane domain {132-152} exoplasmic loop {153-183} MOTIF: N-glycosylation site {N163} N-glycosylation site {N166} transmembrane domain {184-204} cytoplasmic loop {205-211} transmembrane domain {212-232} exoplasmic loop {233-253} transmembrane domain {254-274} cytoplasmic loop {275-286} transmembrane domain {287-307} exoplasmic loop {308-334} transmembrane domain {335-355} cytoplasmic loop {356-374} transmembrane domain {375-395} exoplasmic loop {396-411} transmembrane domain {412-432} cytoplasmic loop {433-441} transmembrane domain {442-462} exoplasmic loop {463-479} transmembrane domain {480-500} cytoplasmic domain {501-744} MOTIF: STAS {525-713}

Database Correlations

OMIM 604943 UniProt P58743 PFAM correlations Kegg hsa:3756