Hepatitis C virus mutation affects proteasomal epitope processing
J. Clin. Invest. Ulrike Seifert, et al. 114:250 doi:10.1172/JCI20985 [Go to this article.]

Figure 2
Digestion of NS3(Wt)_1062–1095 polypeptide and NS3(Mut)_1062–1095 polypeptide with purified 20S immunoproteasomes. (A) The amino acid sequences of the 34-mer NS3(Wt)_1062–1095 and NS3(Mut)_1062–1095 polypeptides are shown in single-letter code. The HLA-A2 restricted CD8⁺ T cell epitope NS3_1073–1081 is framed, and amino acid position NS3₁₀₈₂ containing the wild-type tyrosine or the mutant phenylalanine is circled. The dashed lines indicate the location of proteasomal cuts as deduced from the data shown in panels C–H. (B) NS3(Wt)1062–1095 polypeptide (black bars) and NS3(Mut)_1062–1095 polypeptide (white bars) were digested for 1, 2, 4, and 8 hours with 20S immunoproteasomes. Kinetic analysis of polypeptide substrate turnover is indicated. (C–H) Kinetic analysis of cleavage product generation. Relative abundances of cleavage products derived from immunoproteasomal digestion of NS3(Wt)_1062–1095 polypeptide (filled circles) and NS3(Mut)_1062–1095 polypeptide (open circles) are plotted. The relative abundance of the NS3_1073–1081 epitope could not be assessed due to formation of disulfide bonds that interfered with mass spectrometry analysis.