摘要
Eukaryotic translation initiation factor eIF2B,the guanine nucleotide exchange factor(GEF)for eIF2,catalyzes conversion of eIF2·GDP to eIF2·GTP.The eIF2B is composed of five subunits,α,β,γ,δandε,within which theεsubunit is responsible for catalyzing the guanine exchange reaction.Here we present the crystal structure of the C-terminal domain of human eIF2Bε(eIF2Bε-CTD)at 2.0-Åresolution.The structure resembles a HEAT motif and three charge-rich areas on its surface can be identified.When compared to yeast eIF2Bε-CTD,one area involves highly conserved AA boxes while the other two are only partially conserved.In addition,the previously reported mutations in human eIF2Bε-CTD,which are related to the loss of the GEF activity and human VWM disease,have been discussed.Based on the structure,most of such mutations tend to destabilize the HEAT motif.
基金
This work was supported by the National Programs for High Technology Research and Development Program(863 Program)(Grant No.2006AA02A316)
the National Basic Research Program(973 Program)(Grant Nos.2004CB520801,2006CB910903,2007CB914304,2009CB825501 and 2010CB912301)
the Ministry of Science and Technology,National Natural Science Foundation of China(Grant Nos.30721003 and 30870484)
the Chinese Academy of Sciences(Grant No.KSCX2-YW-R61).