ATP-binding cassette sub-family A member 4 ; RIM ABC transporter ; RIM protein ; Stargardt disease protein ; ABCR
Categories
Elisa
Function
In the visual cycle, acts as an inward-directed retinoid flipase, retinoid substrates imported by ABCA4 from the extracellular or intradiscal (rod) membrane surfaces to the cytoplasmic membrane surface are all-trans-retinaldehyde (ATR) and N-retinyl-phosphatidyl-ethanolamine (NR-PE). Once transported to the cytoplasmic surface, ATR is reduced to vitamin A by trans-retinol dehydrogenase (tRDH) and then transferred to the retinal pigment epithelium (RPE) where it is converted to 11-cis-retinal. May play a role in photoresponse, removing ATR/NR-PE from the extracellular photoreceptor surfaces during bleach recovery.
Specificity
Natural and recombinant Human Retinal-specific ATP-binding cassette transporter
Subcellular Location
Membrane Multi-pass membrane protein Localized to outer segment disk edges of rods and cones, with around one million copies/photoreceptor.