Impaired glycosylation of glycosylphosphatidylinositol-anchor synthesis in paroxysmal nocturnal hemoglobinuria leucocytes.
Metabolic labeling with [3H]sugars in vivo or [3H]sugar nucleotides in vitro of glycosylphosphatidylinositol (GPI)-anchor precursors in peripheral blood granulocytes and cultured T lymphocytes of paroxysmal nocturnal hemoglobinuria (PNH) patients showed a synthetic defect in the GPI-anchor. Among the GPI-anchor precursors, phosphatidylinositol (PI) was normally synthesized, while the synthesis of glucosaminylphosphatidylinositol (GlcN-PI) and subsequent mannosylation of GlcN-PI were inhibited in affected cells. The defect in the GPI-anchor synthesis in PNH is thus attributed to interrupted glycosylation at plural sites in the synthesis of the common carbohydrate structure of the anchor.
Hidaka
M
M
Second Department of Internal Medicine, Kumamoto University School of Medicine, Japan.
Nagakura
S
S
Horikawa
K
K
Kawaguchi
T
T
Iwamoto
N
N
Kagimoto
T
T
Takatsuki
K
K
Nakakuma
H
H
D002240:Carbohydrate Sequence; D002478:Cells, Cultured; D006031:Glycosylation; D017261:Glycosylphosphatidylinositols / Q000096:biosynthesis* / Q000737:chemistry; D006457:Hemoglobinuria, Paroxysmal / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008969:Molecular Sequence Data
D017261:Glycosylphosphatidylinositols