Figure 5. Defective N-linked glycosylation of TβRII suppresses ligand-binding affinity.
(A) Representative flow cytometric analysis of receptor density for recombinant human TGF-β1 (rhTGF-β1) at the cell surface. Various amounts of biotinylated TGF-β1 (2.5–60 ng) were added to 105 HEK-293T cells that were transiently transfected with empty vector, WT or N70/94Q TβRII. The numbers of biotinylated TGF-β1-bound TβRII were quantified using rhTGF-β1. (B) Control Western blot of WT and N70/94Q TβRII transiently transfected into HEK-293T cells used in the ligand-binding assay (A).