Localization, purification, and functional reconstitution of the P4-ATPase Atp8a2, a phosphatidylserine flippase in photoreceptor disc membranes.

ABSTRACT: P(4)-ATPases comprise a relatively new subfamily of P-type ATPases implicated in the energy-dependent translocation of aminophospholipids across cell membranes. In this study, we report on the localization and functional properties of Atp8a2, a member of the P(4)-ATPase subfamily that has not been studied previously. Reverse transcription-PCR revealed high expression of atp8a2 mRNA in the retina and testis. Within the retina, immunofluorescence microscopy and subcellular fractionation studies localized Atp8a2 to outer segment disc membranes of rod and cone photoreceptor cells. Atp8a2 purified from photoreceptor outer segments by immunoaffinity chromatography exhibited ATPase activity that was stimulated by phosphatidylserine and to a lesser degree phosphatidylethanolamine but not by phosph

SUBMITTER: Coleman JA 

PROVIDER: S-EPMC2781682 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature