Functions as an integral cofactor in cell pH regulation by controlling plasma membrane-type Na(+)/H(+) exchange activity. Binds to and activates SLC9A1/NHE1 in a serum-independent manner, thus increasing pH and protecting cells from serum deprivation-induced death. Also plays a role in the regulation of cell proliferation and tumor growth by increasing the phosphatase activity of PPP3CA in a calcium-dependent manner. Activator of the calcineurin/NFAT signaling pathway. Involved in the cytoplasmic translocation of the transcription factor NFATC3 to the nucleus.
Subcellular locations: Nucleus, Cytoplasm, Cell membrane
Predominantly localized in a juxtanuclear region. Colocalizes with SLC9A3 in the juxtanuclear region and at the plasma membrane (By similarity). Exported from the nucleus to the cytoplasm through a nuclear export signal (NES) pathway. May shuttle between nucleus and cytoplasm.
Expressed in malignantly transformed cells but not detected in normal tissues.