ATPase Class VI Type 11B (ATP11B)

P-type ATPases, such as ATP11B, are phosphorylated in their intermediate state and drive uphill transport of ions across membranes. Several subfamilies of P-type ATPases have been identified. One subfamily transports heavy metal ions, such as Cu(2+) or Cd(2+). Another subfamily transports non-heavy metal ions, such as H(+), Na(+), K(+), or Ca(+). A third subfamily transports amphipaths, such as phosphatidylserine.

Nagase et al. (1999) isolated a partial cDNA encoding ATP11B, which they called KIAA0956, from a brain cDNA library. Based on homology analysis, they predicted that the KIAA0956 protein is a chromaffin granule ATPase. RT-PCR analysis detected wide expression, with highest levels in kidney, followed by ovary, corpus callosum, and testis.