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.
Structural basis for self-association and receptor recognition of human TRAF2.,Park YC, Burkitt V, Villa AR, Tong L, Wu H Nature. 1999 Apr 8;398(6727):533-8. PMID:10206649
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Park YC, Burkitt V, Villa AR, Tong L, Wu H. Structural basis for self-association and receptor recognition of human TRAF2. Nature. 1999 Apr 8;398(6727):533-8. PMID:10206649 doi:http://dx.doi.org/10.1038/19110