ATP2B2
Function
ATP-driven Ca(2+) ion pump involved in the maintenance of basal intracellular Ca(2+) levels in specialized cells of cerebellar circuit and vestibular and cochlear systems (PubMed:15829536, PubMed:17234811). Uses ATP as an energy source to transport cytosolic Ca(2+) ions across the plasma membrane to the extracellular compartment (PubMed:15829536, PubMed:17234811). Has fast activation and Ca(2+) clearance rate suited to control fast neuronal Ca(2+) dynamics. At parallel fiber to Purkinje neuron synapse, mediates presynaptic Ca(2+) efflux in response to climbing fiber-induced Ca(2+) rise. Provides for fast return of Ca(2+) concentrations back to their resting levels, ultimately contributing to long-term depression induction and motor learning (By similarity). Plays an essential role in hearing and balance (PubMed:15829536, PubMed:17234811). In cochlear hair cells, shuttles Ca(2+) ions from stereocilia to the endolymph and dissipates Ca(2+) transients generated by the opening of the mechanoelectrical transduction channels. Regulates Ca(2+) levels in the vestibular system, where it contributes to the formation of otoconia (PubMed:15829536, PubMed:17234811). In non-excitable cells, regulates Ca(2+) signaling through spatial control of Ca(2+) ions extrusion and dissipation of Ca(2+) transients generated by store-operated channels (PubMed:25690014). In lactating mammary gland, allows for the high content of Ca(2+) ions in the milk (By similarity).
Involvement in disease
May act as a disease modifier. ATP2B2 variants may exacerbate the severity of non-syndromic sensorineural hearing loss in patients carrying causative variants in the CDH23 gene. Sensorineural deafness results from damage to the neural receptors of the inner ear, the nerve pathways to the brain, or the area of the brain that receives sound information.
Deafness, autosomal dominant, 82
DFNA82
A form of non-syndromic, sensorineural hearing loss. Sensorineural hearing loss results from damage to the neural receptors of the inner ear, the nerve pathways to the brain, or the area of the brain that receives sound information. DNFA82 is characterized by onset of rapidly progressive bilateral sensorineural hearing loss usually early in the first decade.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIB subfamily.
Tissue Specificity
Mainly expressed in brain cortex. Found in low levels in skeletal muscle, heart muscle, stomach, liver, kidney and lung. Isoforms containing segment B are found in brain cortex and at low levels in other tissues. Isoforms containing segments X and W are found at low levels in all tissues. Isoforms containing segment A and segment Z are found at low levels in skeletal muscle and heart muscle.
Cellular localization
- Cell membrane
- Multi-pass membrane protein
- Synapse
- Isoform WA
- Apical cell membrane
- Multi-pass membrane protein
- Basolateral cell membrane
- Multi-pass membrane protein
- Isoform WB
- Apical cell membrane
- Multi-pass membrane protein
- Basolateral cell membrane
- Multi-pass membrane protein
- Isoform XB
- Basolateral cell membrane
- Multi-pass membrane protein
- Isoform ZA
- Basolateral cell membrane
- Multi-pass membrane protein
- Isoform ZB
- Basolateral cell membrane
- Multi-pass membrane protein
Alternative names
PMCA2, ATP2B2, Plasma membrane calcium-transporting ATPase 2, Plasma membrane calcium ATPase isoform 2, Plasma membrane calcium pump isoform 2