4F8T

Crystal Structure of the Human BTN3A3 Ectodomain

Summary for 4F8T

• Entry DOI: 10.2210/pdb4f8t/pdb
• Descriptor: Butyrophilin subfamily 3 member A3 (2 entities in total)
• Functional Keywords: b7 superfamily, butyrophilin, cd277, immune system
• Biological source: Homo sapiens (human)
• Cellular location: Cell membrane; Single-pass type I membrane protein: O00478
• Total number of polymer chains: 1
• Total formula weight: 24451.57

Authors

Palakodeti, A.,Sandstrom, A.,Sundaresan, L.,Harly, C.,Nedellec, S.,Olive, D.,Scotet, E.,Bonneville, M.,Adams, E.J. (deposition date: 2012-05-17, release date: 2012-08-08, Last modification date: 2024-11-27)

Primary citation

Palakodeti, A.,Sandstrom, A.,Sundaresan, L.,Harly, C.,Nedellec, S.,Olive, D.,Scotet, E.,Bonneville, M.,Adams, E.J.
The molecular basis for modulation of human V(gamma)9V(delta)2 T cell response by CD277/Butryophilin (BTN3A)-specific antibodies
J.Biol.Chem., 287:32780-32790, 2012

PubMed Abstract: Human Vγ9Vδ2 T cells are well known for their rapid and potent response to infection and tumorigenesis when in the presence of endogenous or exogenous phosphoisoprenoids. However, the molecular mechanisms behind the activation of this γδ T cell population remains unclear. Evidence pointing to a role for the CD277/butyrophilin-3 (BTN3A) molecules in this response led us to investigate the structures of these molecules and their modifications upon binding to an agonist antibody (20.1) that mimics phosphoisoprenoid-mediated Vγ9Vδ2 activation and an antagonist antibody (103.2) that inhibits this reactivity. We find that the three BTN3A isoforms: BTN3A1, BTN3A2, and BTN3A3, have high structural homology to the B7 superfamily of proteins and exist as V-shaped homodimers in solution, associating through the membrane proximal C-type Ig domain. The 20.1 and 103.2 antibodies bind to separate epitopes on the BTN3A Ig-V domain with high affinity but likely with different valencies based on their binding orientation. These structures directly complement functional studies of this system that demonstrate that BTN3A1 is necessary for Vγ9Vδ2 activation and begin to unravel the extracellular events that occur during stimulation through the Vγ9Vδ2 T cell receptor.

PubMed: 22846996
DOI: 10.1074/jbc.M112.384354

Experimental method

X-RAY DIFFRACTION (2.382 Å)