07/03/2023
TCR alpha and beta chains, when dimerized, create an unique object, a receptor, which recognizes the antigen presented by the MHC system, like a “key-lock” mechanism. For the case of the 1E6 receptors and its insulin antigen “YQFGPDFPIA” (green), the recognition happens thanks to two strands of amino acids, “GDSSY” in the alpha chain (orange) and, “WEKLA”, in the beta chain (blue). They are both part of the CDR3, (Complementary-determining region 3), located in the two TCR chains.
The central part of the antigen, containing a “GPD” sequence, represents the part of the peptide mainly recognized by GDSSY and WEKLA.
For more information about this model see the link:
https://www.rcsb.org/3d-view/5C07/1
And the paper by David Cole and Andrew Sewell:
https://www.jci.org/articles/view/85679