Na+/K+/Ca+2-exchange protein 1 (retinal rod Na+/Ca+2/K+ exchanger, SLC24A1, KIAA0702, NCKX1)

Function

• component of the visual transduction cascade,
• controls Ca+2 concentration of outer segments during light & darkness
• light causes a rapid lowering of cytosolic free Ca+2 in the outer segment of both retinal rod & cone photoreceptors
• light-induced lowering of Ca+2 is caused by extrusion via SLC24A1 (this protein)
• transports 1 Ca+2 & 1 K+ in exchange for 4 Na+
• uncleaved signal sequence is required for efficient membrane targeting & proper membrane integration
• role in light adaptation

Structure

belongs to the Na+/K+/Ca+2 exchanger family, SLC24A subfamily

Compartment

membrane

Alternative splicing

named isoforms=2

Expression

• found only in outer segments of retinal rod photoreceptors

More general terms

• transmembrane 11e protein
• solute carrier family 24 (SLC24, SLC24A)
• glycoprotein
• phosphoprotein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:9187
• OMIM: https://mirror.omim.org/entry/603617
• UniProt: http://www.uniprot.org/uniprot/O60721.html