Summary
PDB 1DR9 deposited: 2000-01-06 modified: 2011-07-13
Title CRYSTAL STRUCTURE OF A SOLUBLE FORM OF B7-1 (CD80)
Authors Collins, A.V., Davis, S.J., Fennelly, J.A., Gilbert, R.J., Harlos, K., Ikemizu, S., Jones, E.Y., Stuart, D.I.
Method X-RAY DIFFRACTION
Structure factors resolution 3.0 rfactor 0.238 rfree 0.28
DPI 1.99 theoretical min: 0.62
Citations

B7-1 (CD80) and B7-2 (CD86) are glycoproteins expressed on antigen-presenting cells. The binding of these molecules to the T cell homodimers CD28 and CTLA-4 (CD152) generates costimulatory and inhibitory signals in T cells, respectively. The crystal structure of the extracellular region of B7-1 (sB7-1), solved to 3 A resolution, consists of a novel combination of two Ig-like domains, one characteristic of adhesion molecules and the other previously seen only in antigen receptors. In the crystal lattice, sB7-1 unexpectedly forms parallel, 2-fold rotationally symmetric homodimers. Analytical ultracentrifugation reveals that sB7-1 also dimerizes in solution. The structural data suggest a mechanism whereby the avidity-enhanced binding of B7-1 and CTLA-4 homodimers, along with the relatively high affinity of these interactions, favors the formation of very stable inhibitory signaling complexes.

Immunity 2000 Jan; 12(1):51-60 doi:10.1016/S1074-7613(00)80158-2

Cross References
Database source Identifier Description
PubMed 10661405 IUNIEH
Biomolecule Structure Assembly Serial Assembly Type Conformational State Chains Ligands Atoms
1DR9/0 1DR9 0 monomer 0 1 3 1554