Biochemical analysis of glycophospholipids from wild-type mouse lymphoma cells and from Thy-1 negative mutants which do not add glycolipid-anchored proteins.

Thy-1 is a major glycophospholipid (GPL)-anchored protein found on the surface of neurons, epithelial cells, fibroblasts and murine T-lymphomas. Biochemical studies were undertaken to determine if murine T-lymphomas contain glycolipids which may be on the path of GPL-anchor biosynthesis. Biosynthetic labeling experiments on Thy-1-positive (wild-type) cells followed by battery of chemical and enzymatic diagnostics on the isolated [3H]mannolipids have, for the first time, led to description of a set of glycolipids which have properties consistent with their being GPL-anchor precursors. Using these results as a guide, major differences have been observed upon analysis of the radiolabeled mannolipids of Thy-1-negative mutants from 7 complementation classes, A-C, E, F, H and I. The biosynthetic lesions in anchor synthesis have been identified in some of the mutants.