1DR9

CRYSTAL STRUCTURE OF A SOLUBLE FORM OF B7-1 (CD80)

Summary for 1DR9

• Entry DOI: 10.2210/pdb1dr9/pdb
• Descriptor: T LYMPHOCYTE ACTIVATION ANTIGEN, 2-acetamido-2-deoxy-beta-D-glucopyranose (2 entities in total)
• Functional Keywords: ig superfamily, immune system
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 1
• Total formula weight: 23656.75

Authors

Ikemizu, S.,Jones, E.Y.,Stuart, D.I.,Davis, S.J. (deposition date: 2000-01-06, release date: 2000-01-10, Last modification date: 2024-10-16)

Primary citation

Ikemizu, S.,Gilbert, R.J.,Fennelly, J.A.,Collins, A.V.,Harlos, K.,Jones, E.Y.,Stuart, D.I.,Davis, S.J.
Structure and dimerization of a soluble form of B7-1.
Immunity, 12:51-60, 2000

PubMed Abstract: 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.

PubMed: 10661405
DOI: 10.1016/S1074-7613(00)80158-2

Experimental method

X-RAY DIFFRACTION (3 Å)