Na+/K+ Transporting ATPase Interacting Protein 3 (NKAIN3)

Sodium/potassium-transporting ATPase subunit beta-1-interacting protein 3 is a member of a family of mammalian proteins with similarity to Drosophila Nkain. Using EST database analysis to screen for novel proteins expressed in the mammalian central nervous system, followed by RT-PCR of mouse brain RNA, Gorokhova et al. (2007) cloned mouse Nkain3 and identified human NKAIN3.

NKAIN3 contains a predicted cleavable signal peptide and 3 putative transmembrane domains. Mouse Nkain3 shares 60% amino acid similarity with the first 200 amino acids of the Drosophila ortholog, which extends for an additional 458 amino acids in a C-terminal tail absent from vertebrate Nkain3. RT-PCR analysis detected expression in mouse brain and testis only.