TRAF3 Interacts with Smac/DIABLO and Enhances the Proapoptotic Effect of Smac/DIABLO in Cytoplasm

作     者：Cuili ZHANG~(1,2) Lei XIE~4 Hai'en CHENG~3 and Yingxiong WANG~2 ~1Clinical Laboratory,Sichuan Corps Hospital of The people's Armed Police Forces,Leshan 614000,China ~2Department of Procreation Medicine,Chongqing Medical Universtity,Chongqing 400016,China ~3Clinical Laboratory,Second Affiliated Hospital Zhejiang University College of Medicine,Hangzhou 310009,China ~4Sitchuan Corps Hospital The People's Armed Police Forces,Leshan 614000,China 

作者机构：ClinicalLaboratory.Sichuan.CorpsHospital.ofThePeople'sArmedPoliceForcesLeshan614000China DepartmentofProcreationMedicine.ChongqingMedicalUniversityChongqing400016China 

出 版 物：《Acta Biochimica et Biophysica Sinica》 (生物化学与生物物理学报(英文版))

年 卷 期：2007年第39卷第2期

页      面：108-116页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 071009[理学-细胞生物学] 09[农学] 0901[农学-作物学] 090102[农学-作物遗传育种] 

主　　题：Smac/DIABLO TRAF3 apoptosis yeast two-hybrid system GST-pull down assay 

摘      要：Smac/DIABLO (second mitochondria-derived activator of caspase/direct IAP-binding proteinwith low PI) is a 29 kDa mitochondrial precursor protein,which is proteolytically processed in mitochondriainto a 23 kDa mature *** is released from the mitochondrial intermembrane space to cytosol after anapoptotic ***/DIABLO acts as a dimer and it contributes to caspase activation by sequestering theinhibitor of apoptosis proteins (IAPs).In order to further investigate the mechanism of Smac/DIABLOaction,we used the mature form of Smac/DIABLO as a bait and screened proteins that interact with matureSmac/DIABLO in human liver cDNA library using the yeast two-hybrid ***-two colonies wereobtained after 5.8x 10～6 colonies were screened by nutrition limitation and X-galactosidase *** DNAsequence analysis and homology retrieval,one of the candidate proteins was identified as TRAF domain ofthe TNF receptor associated factor 3 (TRAF3).The interaction site between TRAF3 and Smac/DIABLOwas identified by β-galactosidase test. The interaction between TRAF3 and Smac/DIABLO via TRAF domainwas identified in vivo by co-immunoprecipitation in HepG2 cells,and the direct interaction between TRAF3and Smac/DIABLO in vitro was identified by GST-pull down ***-expression of TRAF3 and matureSmac/DIABLO in 293 cells could enhance the Smac/DIABLO-mediated *** results suggestedthat TRAF3 interacted with Smac/DIABLO via TRAF domain,leading to an increased proapoptotic effectof Smac/DIABLO in cytoplasm.