The crystal structure of the carboxy-terminal domain of human translation initiation factor eIF5.
The carboxy-terminal domain (CTD) of eukaryotic initiation factor 5 (eIF5) plays a central role in the formation of the multifactor complex (MFC), an important intermediate for the 43 S pre-initiation complex assembly. The IF5-CTD interacts directly with the translation initiation factors eIF1, eIF2-beta, and eIF3c, thus forming together with eIF2 bound Met-tRNA(i)(Met) the MFC. In this work we present the high resolution crystal structure of eIF5-CTD. This domain of the protein is exclusively composed out of alpha-helices and is homologous to the carboxy-terminal domain of eIF2B-epsilon (eIF2Bepsilon-CTD). The most striking difference in the two structures is an additional carboxy-terminal helix in eIF5. The binding sites of eIF2-beta, eIF3 and eIF1 were mapped onto the structure. eIF2-beta and eIF3 bind to non-overlapping patches of negative and positive electrostatic potential, respectively.
Bieniossek
Christoph
C
Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern, Switzerland.
Schütz
Patrick
P
Bumann
Mario
M
Limacher
Andreas
A
Uson
Isabel
I
Baumann
Ulrich
U
D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D002850:Chromatography, Gel; D018360:Crystallography, X-Ray; D040061:Eukaryotic Initiation Factor-5 / Q000737:chemistry*; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D013696:Temperature
D040061:Eukaryotic Initiation Factor-5