TRAF4 is a unique member of TRAF family,which is es-sential for innate immune response,nervous system and other systems.In addition to being an adaptor protein,TRAF4 was identifi ed as a regulator protein in recent st...TRAF4 is a unique member of TRAF family,which is es-sential for innate immune response,nervous system and other systems.In addition to being an adaptor protein,TRAF4 was identifi ed as a regulator protein in recent studies.We have determined the crystal structure of TRAF domain of TRAF4(residues 292-466)at 2.60Åresolution by X-ray crystallography method.The trimericly assembled TRAF4 resembles a mushroom shape,containing a super helical“stalk”which is made of three right-handed intertwinedαhelixes and a C-terminal“cap”,which is divided at resi-due L302 as a boundary.Similar to other TRAFs,both intermolecular hydrophobic interaction in super helical“stalk”and hydrogen bonds in“cap”regions contribute directly to the formation of TRAF4 trimer.However,differ-ing from other TRAFs,there is an additional fl exible loop(residues 421-426),which contains a previously identifi ed phosphorylated site S426 exposing on the surface.This S426 was reported to be phosphorylated by IKKαwhich is the pre-requisite for TRAF4-NOD2 complex formation and thus to inhibit NOD2-induced NF-κB activation.Therefore,the crystal structure of TRAF4-TRAF is valuable for under-standing its molecular basis for its special function and provides structural information for further studies.展开更多
基金the Ministry of Health of China(grant 2013ZX10004-602)the National Basic Research Program(973 Program)(Nos.2013CB911103,2009DFB30310,2009CB918803 and 2011CB911103)the National Natural Science Foundation of China(Grant Nos.31270795,31200559,31070660 and 31021062).
文摘TRAF4 is a unique member of TRAF family,which is es-sential for innate immune response,nervous system and other systems.In addition to being an adaptor protein,TRAF4 was identifi ed as a regulator protein in recent studies.We have determined the crystal structure of TRAF domain of TRAF4(residues 292-466)at 2.60Åresolution by X-ray crystallography method.The trimericly assembled TRAF4 resembles a mushroom shape,containing a super helical“stalk”which is made of three right-handed intertwinedαhelixes and a C-terminal“cap”,which is divided at resi-due L302 as a boundary.Similar to other TRAFs,both intermolecular hydrophobic interaction in super helical“stalk”and hydrogen bonds in“cap”regions contribute directly to the formation of TRAF4 trimer.However,differ-ing from other TRAFs,there is an additional fl exible loop(residues 421-426),which contains a previously identifi ed phosphorylated site S426 exposing on the surface.This S426 was reported to be phosphorylated by IKKαwhich is the pre-requisite for TRAF4-NOD2 complex formation and thus to inhibit NOD2-induced NF-κB activation.Therefore,the crystal structure of TRAF4-TRAF is valuable for under-standing its molecular basis for its special function and provides structural information for further studies.
