CHO2.46 cells accumulate GlcN-acyl-PI. (A) Cells were metabolically labeled with [3H]Man in the absence (lanes 1, 2, and 3) or presence (lanes 4 and 5) of YW3548/BE49385A, and Man-containing lipids were analyzed by TLC. Lane 1, parental CHO F21; lane 2, mutant CHO2.46; lane 3, PIG-U–defective mutant CHO PA16.1; lane 4, CHO F21; and lane 5, CHO2.46. DPM, Dol-P-Man; H2-H8, Man containing GPI species (Hong et al., 2003); H7′, GPI species that accumulated in the presence of YW3548/BE49385A (Hong et al., 1999). (B) Cells were metabolically labeled with myo-[3H]inositol. Lane 1, CHO F21; lane 2, PIG-L–defective mutant CHO1.46; lane 3, PIG-W–defective mutant CHO10.14; lane 4, CHO2.46; lane 5, Dol-P-Man synthase-defective mutant CHO2.38.