Proteomic analysis of glycosylphosphatidylinositol-anchored membrane proteins.
Glycosylphosphatidylinositol-anchored proteins (GPI-APs) are a functionally and structurally diverse family of post-translationally modified membrane proteins found mostly in the outer leaflet of the plasma membrane in a variety of eukaryotic cells. Although the general role of GPI-APs remains unclear, they have attracted attention because they act as enzymes and receptors in cell adhesion, differentiation, and host-pathogen interactions. GPI-APs may represent potential diagnostic and therapeutic targets in humans and are interesting in plant biotechnology because of their key role in root development. We here present a general mass spectrometry-based proteomic "shave-and-conquer" strategy that specifically targets GPI-APs. Using a combination of biochemical methods, mass spectrometry, and computational sequence analysis we identified six GPI-APs in a Homo sapiens lipid raft-enriched fraction and 44 GPI-APs in an Arabidopsis thaliana membrane preparation, representing the largest experimental dataset of GPI-anchored proteins to date.
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000378:metabolism; D002853:Chromatography, Liquid; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D013058:Mass Spectrometry; D021962:Membrane Microdomains / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D040901:Proteomics
D017261:Glycosylphosphatidylinositols; D008565:Membrane Proteins