Major differences in transporter associated with antigen presentation (TAP)-dependent translocation of MHC class I-presentable peptides and the effect of flanking sequences.

摘要: The MHC-encoded transporter associated with Ag presentation (TAP) translocates peptides from the cytosol to ER lumen, where association MHC class I molecules occurs. I/peptide complex is subsequently transported cell surface for CD8+T cells. We studied TAP-dependent translocation of defined presentable murine by competition a radiolabeled model peptide, address whether efficient peptide preceded equal TAP. Surprisingly, we observed that four immunodominant viral 16 tested were very inefficiently Inefficient could be overcome substitution proline residue present at position 3 in peptides. Furthermore, addition natural flanking amino acids directly surrounding poorly considerably improve Our data suggest some are efficiently TAP their optimal size binding, whereas other as larger fragments need further trimming binding.