ATP1A3. The ATPases are the “Sisphyean” workhorses of cells, perpetually bound to utilize energy generated by mitochondria to pump ions across cell membranes. This is essential to the maintenance of the intra/extracellular electrochemical gradient. ATP1A3 codes for the α3 subunit of the Na+-K+ ATPase, which utilizes ATP to actively transport sodium out of the cell and potassium into the cell. In the brain, this gradient is critical for cell signaling and for maintaining electrochemical stability, enabling cell excitation and action potential propagation. Both ATP1A3 and one of its counterparts, ATP1A2, are expressed in neurons during embryonal brain development, and ATP1A3 is also thought to contribute to regulation of non-ionic neuronal transporters and receptors. However, whereas ATP1A2 is primarily expressed in glial cells postnatally and into adulthood, ATP1A3 continues to be expressed primarily in neurons, with particular enrichment in excitatory neurons. Here is a brief overview of the clinical spectrum of ATP1A3-related disorders.
