Structural basis for self-association and receptor recognition of human TRAF2.
Park, Y.C., Burkitt, V., Villa, A.R., Tong, L., Wu, H.(1999) Nature 398: 533-538
- PubMed: 10206649 
- DOI: https://doi.org/10.1038/19110
- Primary Citation of Related Structures:  
1CA4, 1CA9 - PubMed Abstract: 
Tumour necrosis factor (TNF)-receptor-associated factors (TRAFs) form a family of cytoplasmic adapter proteins that mediate signal transduction from many members of the TNF-receptor superfamily and the interleukin-1 receptor. They are important in the regulation of cell survival and cell death. The carboxy-terminal region of TRAFs (the TRAF domain) is required for self-association and interaction with receptors. The domain contains a predicted coiled-coil region that is followed by a highly conserved TRAF-C domain. Here we report the crystal structure of the TRAF domain of human TRAF2, both alone and in complex with a peptide from TNF receptor-2 (TNF-R2). The structures reveal a trimeric self-association of the TRAF domain, which we confirm by studies in solution. The TRAF-C domain forms a new, eight-stranded antiparallel beta-sandwich structure. The TNF-R2 peptide binds to a conserved shallow surface depression on one TRAF-C domain and does not contact the other protomers of the trimer. The nature of the interaction indicates that an SXXE motif may be a TRAF2-binding consensus sequence. The trimeric structure of the TRAF domain provides an avidity-based explanation for the dependence of TRAF recruitment on the oligomerization of the receptors by their trimeric extracellular ligands.
Organizational Affiliation: 
Department of Biochemistry, The Weill Medical College and Graduate School of Medical Sciences of Cornell University, New York, New York 10021, USA.