51. Delineation of an extended surface contact area on human CD4 involved in class II major histocompatibility complex binding
- Author
-
Stephen C. Harrison, Ulrich Moebius, Peter Pallai, and Ellis L. Reinherz
- Subjects
Models, Molecular ,Protein Conformation ,Molecular Sequence Data ,Fluorescent Antibody Technique ,Major histocompatibility complex ,Transfection ,Protein Structure, Secondary ,Domain (software engineering) ,Cell Line ,Protein structure ,Antigen ,Antigens, CD ,Animals ,Amino Acid Sequence ,Binding site ,Site-directed mutagenesis ,Peptide sequence ,Genetics ,HLA-D Antigens ,Multidisciplinary ,Binding Sites ,biology ,MHC Interaction ,Recombinant Proteins ,CD4 Antigens ,biology.protein ,Biophysics ,Mutagenesis, Site-Directed ,Research Article - Abstract
We describe a detailed mapping of the class II major histocompatibility complex (MHC) binding site using site-directed mutagenesis in conjunction with high-resolution CD4 structural data. Residues on all lateral surfaces of domain 1 and the neighboring portions of domain 2 participate in contacting class II MHC. Thus, in addition to the C'C" ridge that forms the human immunodeficiency virus type 1 gp120 binding site, apparent MHC contacts extend over the BED face of domain 1 and across the interdomain groove onto the FG loop of domain 2. Several models of the CD4/class II MHC interaction accounting for the extent of the CD4 surface involved are discussed, including the possibility that CD4 may contact more than one class II MHC molecule using different surfaces.
- Published
- 1993