markhodes at aol.com (Mark Hodes) writes:
>Jonathan Sprent in Paul, Ch.3, writes that it's an open question whether
>TcR has two adjacent binding sites: one for self MHC and one for foreign
>peptide or has one binding site for MHC+peptide complex. Diagrams in
>Benjamin & Leskowitz (1993), in Paul (1993) ch. 1, and Sprent in Paul,
>Ch.3, all seem to accept the second view. Comments? Mark Hodes
>(markhodes at aol.com)
The two separate site idea is an older concept. If you look at the
crystal structure of MHC (HLA A2 Bjorkman et al) you see that the peptide
is nestled in a "clamshell" like structure in the MHC. It would be
pretty hard for the T-cell receptor to just contact the peptide at this
place and only contact the MHC somewhere else. Of course different
residues in the T-cell receptor contact MHC and peptide, but they are
in the same area (site).
--
| \ o IO | "If we do not find | Erik Wilson |
|-----| o GANYMEDE |anything pleasant, at | University of Illinois |
| O | o EUROPA |least we will find | (217) 359-7547 |
|----/ o CALLISTO |something new" -Voltaire| erikred at uiuc.edu |