Molecular architecture of the αβ T cell receptor-CD3 complex.

ABSTRACT: αβ T-cell receptor (TCR) activation plays a crucial role for T-cell function. However, the TCR itself does not possess signaling domains. Instead, the TCR is noncovalently coupled to a conserved multisubunit signaling apparatus, the CD3 complex, that comprises the CD3εγ, CD3εδ, and CD3ζζ dimers. How antigen ligation by the TCR triggers CD3 activation and what structural role the CD3 extracellular domains (ECDs) play in the assembled TCR-CD3 complex remain unclear. Here, we use two complementary structural approaches to gain insight into the overall organization of the TCR-CD3 complex. Small-angle X-ray scattering of the soluble TCR-CD3εδ complex reveals the CD3εδ ECDs to sit underneath the TCR α-chain. The observed arrangement is consistent with EM images of the entire TCR-CD3 integral mem

SUBMITTER: Birnbaum ME 

PROVIDER: S-EPMC4267357 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature