Na+/hydrogen exchanger 9; Na+/H+ exchanger 9; NHE-9; solute carrier family 9 member 9 (SLC9A9, NHE9, Nbla00118)

Function

• may act in electroneutral exchange of protons for Na+ across membranes
• involved in the effusion of Golgi luminal H+ in exchange for cytosolic cations
• involved in organelle ion homeostasis by contributing to maintenance of the acidic pH of the Golgi & post-Golgi compartments

Structure

• belongs to the monovalent cation:proton antiporter 1 (CPA1) transporter (TC 2.A.36) family

Compartment

• late endosome membrane; multi-pass membrane protein

Expression

• ubiquitously expressed in all tissues tested
• expressed at highest levels in heart & skeletal muscle, -lesser expression in placenta, kidney, & liver
• expressed in brain, medulla oblongata & spinal cord

Pathology

• chromosomal inversion inv(3)(p14:q21) involving DOCK3 & SLC9A9 associated with ADHD
• defects in SLC9A9 are a cause of susceptibility to autism type 16

More general terms

• solute carrier family 9 (SLC9, SLC9A)
• Na+/H+ antiporter
• transmembrane 13 protein

Additional terms

• attention-deficit hyperactivity disorder (ADHD)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=285195
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:285195
• OMIM: https://mirror.omim.org/entry/608396
• OMIM: https://mirror.omim.org/entry/613410
• UniProt: http://www.uniprot.org/uniprot/Q8IVB4.html