Download MendeleyStructure of murine CTLA-4 and its role in modulating T cell responsiveness.
Ostrov, D.A., Shi, W., Schwartz, J.C., Almo, S.C., Nathenson, S.G.(2000) Science 290: 816-819
- PubMed: 11052947
- DOI: https://doi.org/10.1126/science.290.5492.816
- Primary Citation of Related Structures:
1DQT - PubMed Abstract:
The effective regulation of T cell responses is dependent on opposing signals transmitted through two related cell-surface receptors, CD28 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4). Dimerization of CTLA-4 is required for the formation of high-avidity complexes with B7 ligands and for transmission of signals that attenuate T cell activation. We determined the crystal structure of the extracellular portion of CTLA-4 to 2.0 angstrom resolution. CTLA-4 belongs to the immunoglobulin superfamily and displays a strand topology similar to Valpha domains, with an unusual mode of dimerization that places the B7 binding sites distal to the dimerization interface. This organization allows each CTLA-4 dimer to bind two bivalent B7 molecules and suggests that a periodic arrangement of these components within the immunological synapse may contribute to the regulation of T cell responsiveness.
Organizational Affiliation:
Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
