期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1999
卷号:96
期号:15
页码:8621-8626
DOI:10.1073/pnas.96.15.8621
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We discuss here the problems in identifying sequence motifs of peptides that bind to I-Ag7, the class II histocompatibility molecule of NOD diabetic mice. We present studies that indicate a minor contribution of amino acid side chains for binding. A peptide from the E chain binds to I-Ag7 molecules and is recognized by CD4 T cells. By producing single-residue mutations we identified four residues that were considered to contact the T cell receptor. No residue was found to be essential for binding to I-Ag7: a peptide that contained the T cell contact residues, on a backbone of alanines, bound to I-Ag7 and stimulated the T cells. We conclude that peptides can bind to I-Ag7 without the requirement for residues with prominent side chains to anchor them.