FXYD Domain Containing Ion Transport Regulator 3 (FXYD3)

FXYD3 encodes a member of a family of small membrane proteins that share a 35-amino acid signature sequence domain, beginning with the sequence PFXYD and containing 7 invariant and 6 highly conserved amino acids. FXYD1, FXYD2, FXYD3, FXYD4, and FXYD5 have been shown to induce channel activity in experimental expression systems. Transmembrane topology has been established for two family members (FXYD1 and FXYD2), with the N-terminus extracellular and the C-terminus on the cytoplasmic side of the membrane. The protein encoded by this gene may function as a chloride channel or as a chloride channel regulator. Two transcript variants encode two different isoforms of the protein; in addition, transcripts utilizing alternative polyA signals have been described in the literature.