Fig. 5.

Cytoplasmic lysine residues are not required for degradation of CD8 containing only a luminal folding defect. (A,B) Degradation of CD8^LUM* and CD8^LUM*3KR was examined by cycloheximide chase assays as in Fig. 3A,B. (C) Cells were induced with tetracycline (tet) or left uninduced, then lysed and the CD8 immunoprecipitated (IP) with anti-HA antibodies. Samples were analysed by immunoblotting with anti-ubiquitin and anti-HA antibodies. *HC, IgG heavy chain; Ub_n, polyubiquitylated proteins; T, 5% of the total input; IP, immunoprecipitated sample. (D) Dislocation of CD8^LUM* and CD8^LUM*3KR was examined as in Fig. 4F. u, the unglycosylated precursor of CD8; *deg, degradation product. (E,F) Degradation of CD8^L*M* and CD8^L*M*3KR was examined by cycloheximide chase assays as in Fig. 3A,B.