Title : Crystal structure of MHC class II I-Ab in complex with a human
CLIP peptide : prediction of an I-Ab peptide-binding
motif
Abstract :
- Association between the class II major histocompatibility complex (MHC) and the class II invariant chain-associated peptide ( CLIP ) occurs naturally as an intermediate step in the MHC class II processing pathway
- Here, we report the crystal structure of the murine class II MHC molecule I-A(b) in complex with human CLIP at 2.15A resolution
- The structure of I-A(b) accounts, via the peptide-binding groove's unique physicochemistry, for the distinct peptide repertoire bound by this allele
- CLIP adopts a similar conformation to peptides bound by other I-A alleles, reinforcing the notion that CLIP is presented as a conventional peptide antigen
- When compared to the related HLA-DR3/CLIP complex structure , the CLIP peptide displays a slightly different conformation and distinct interaction pattern with residues in I-A(b)
- In addition, after examining the published sequences of peptides presented by I-A(b), we discuss the possibility of predicting peptide alignment in the I-A(b) binding groove using a simple scoring matrix