Download MendeleyCrystal structure of the N-terminal segment of human eukaryotic translation initiation factor 2alpha
Nonato, M.C., Widom, J., Clardy, J.(2002) J Biological Chem 277: 17057-17061
- PubMed: 11859078
- DOI: https://doi.org/10.1074/jbc.M111804200
- Primary Citation of Related Structures:
1KL9 - PubMed Abstract:
Eukaryotic translation initiation factor 2alpha (eIF2alpha) is a member of the eIF2 heterotrimeric complex that binds and delivers Met-tRNA(i)(Met) to the 40 S ribosomal subunit in a GTP-dependent manner. Phosphorylation/dephosphorylation of eIF2alpha at Ser-51 is the major regulator of protein synthesis in eukaryotic cells. Here, we report the first structural analysis on eIF2, the three-dimensional structure of a 22-kDa N-terminal portion of human eIF2alpha by x-ray diffraction at 1.9 A resolution. This structure contains two major domains. The N terminus is a beta-barrel with five antiparallel beta-strands in an oligonucleotide binding domain (OB domain) fold. The phosphorylation site (Ser-51) is on the loop connecting beta3 and beta4 in the OB domain. A helical domain follows the OB domain, and the first helix has extensive interactions, including a disulfide bridge, to fix its orientation with respect to the OB domain. The two domains meet along a negatively charged groove with highly conserved residues, indicating a likely site for protein-protein interaction.
Organizational Affiliation:
Department of Chemistry, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
