Correction of the class H defect in glycosylphosphatidylinositol anchor biosynthesis in Ltk- cells by a human cDNA clone.

Previous attempts to express glycosylphosphatidylinositol-anchored proteins in Ltk- cells have not been successful because Ltk- cells cannot synthesize N-acetylglucosamine-phosphatidylinositol, the first intermediate in anchor biosynthesis. Using complementation cloning, we have identified a human cDNA that corrects the defect in anchor biosynthesis and allows the expression of glycosylphosphatidylinositol-anchored proteins in Ltk- cells. The nucleotide sequence predicts a novel cytosolic protein of 188 amino acids.