Protein: Sodium/hydrogen exchanger 9B2 (Na(+)/H(+) exchanger NHA2) (Na(+)/H(+) exchanger-like domain-containing protein 2) (NHE domain-containing protein 2) (Sodium/hydrogen exchanger-like domain-containing protein 2) (Solute carrier family 9 subfamily B member 2) (Q86UD5)
Organism: Homo sapiens (Human)
Function: Na(+)/H(+) antiporter that extrudes Na(+) or Li(+) in exchange for external protons across the membrane. Contributes to the regulation of intracellular pH, sodium homeostasis, and cell volume. Plays an important role for insulin secretion and clathrin-mediated endocytosis in beta-cells (By similarity). Involved in sperm motility and fertility (By similarity). It is controversial whether SLC9B2 plays a role in osteoclast differentiation or not (By similarity).
Subcellular location: Cell membrane {ECO:0000269|PubMed:18000046, ECO:0000269|PubMed:36177733}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Mitochondrion membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Endosome membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Recycling endosome membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Cell projection, cilium, flagellum membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Basolateral cell membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Apical cell membrane {ECO:0000250|UniProtKB:Q5BKR2}; Multi-pass membrane protein {ECO:0000250|UniProtKB:A0A6P3HVI0}. Note=Strong colocalization with LAMP1 and TCIRG1 in osteoclasts. In beta-cells colocalizes with RAB4A and SYP. Localizes to the basolateral membrane of polarized osteoclasts. {ECO:0000250|UniProtKB:Q5BKR2}.
InterPro domains:
- IPR006153: Cation/H+ exchanger, transmembrane domain (domain) [136-509]
- IPR051843: Monovalent cation:proton antiporter 1 (family) [5-533]
- IPR038770: Sodium/solute symporter superfamily (homologous_superfamily) [112-518]
Sequence:
MGDEDKRITYEDSEPSTGMNYTPSMHQEAQEETVMKLKGIDANEPTEGSILLKSSEKKLQETPTEANHVQRLRQMLACPPHGLLDRVITNVTIIVLLWAVVWSITGSECLPGGNLFGIIILFYCAIIGGKLLGLIKLPTLPPLPSLLGMLLAGFLIRNIPVINDNVQIKHKWSSSLRSIALSIILVRAGLGLDSKALKKLKGVCVRLSMGPCIVEACTSALLAHYLLGLPWQWGFILGFVLGAVSPAVVVPSMLLLQGGGYGVEKGVPTLLMAAGSFDDILAITGFNTCLGIAFSTGSTVFNVLRGVLEVVIGVATGSVLGFFIQYFPSRDQDKLVCKRTFLVLGLSVLAVFSSVHFGFPGSGGLCTLVMAFLAGMGWTSEKAEVEKIIAVAWDIFQPLLFGLIGAEVSIASLRPETVGLCVATVGIAVLIRILTTFLMVCFAGFNLKEKIFISFAWLPKATVQAAIGSVALDTARSHGEKQLEDYGMDVLTVAFLSILITAPIGSLLIGLLGPRLLQKVEHQNKDEEVQGETSVQV
Predicted GO terms:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005215 (transporter activity), GO:0022857 (transmembrane transporter activity), GO:1901702 (salt transmembrane transporter activity), GO:0015075 (monoatomic ion transmembrane transporter activity), GO:0015318 (inorganic molecular entity transmembrane transporter activity), GO:0022804 (active transmembrane transporter activity), GO:0022890 (inorganic cation transmembrane transporter activity), GO:0022853 (active monoatomic ion transmembrane transporter activity), GO:0008324 (monoatomic cation transmembrane transporter activity), GO:0015081 (sodium ion transmembrane transporter activity), GO:0015291 (secondary active transmembrane transporter activity), GO:0015297 (antiporter activity), GO:0015078 (proton transmembrane transporter activity), GO:0046873 (metal ion transmembrane transporter activity), GO:0140828 (metal cation:monoatomic cation antiporter activity), GO:0015385 (sodium:proton antiporter activity), GO:0051139 (metal cation:proton antiporter activity)
Biological Process (BP): GO:0008150 (biological process), GO:0009987 (cellular process), GO:0051179 (localization), GO:0051234 (establishment of localization), GO:0055085 (transmembrane transport), GO:0006810 (transport), GO:0034220 (monoatomic ion transmembrane transport), GO:0006811 (monoatomic ion transport)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0071944 (cell periphery), GO:0016020 (membrane), GO:0005886 (plasma membrane)