Biosynthesis and processing of murine T-cell antigen receptor.

The antigen-specific receptor of C6VL T-lymphoma cells is a disulfide-linked heterodimer composed of 39 kd alpha chain and a 41 kd beta chain, both of which exhibit charge microheterogeneity. Pulse-chase labeling experiments indicate that epitopes reactive with the anti-receptor xenoantiserum #8177 were detectable by 2 min, while the clonotypic epitope reactive with monoclonal antibody 124-40 was not detectable until 10 min. Digestion with endoglycosidases H and F revealed that both subunits have at least three N-linked oligosaccharide side chains. The deglycosylated alpha and beta subunits were 27 and 32 kd, respectively. These data suggest that the dimeric receptor is formed shortly after translation, followed by extensive glycosylation. Emergence of the C6VL clonotypic epitope, and perhaps the antigen binding site, may therefore be dependent on post-assembly events.