Download MendeleyCdc123, a Cell Cycle Regulator Needed for eIF2 Assembly, Is an ATP-Grasp Protein with Unique Features.
Panvert, M., Dubiez, E., Arnold, L., Perez, J., Mechulam, Y., Seufert, W., Schmitt, E.(2015) Structure 23: 1596-1608
- PubMed: 26211610
- DOI: https://doi.org/10.1016/j.str.2015.06.014
- Primary Citation of Related Structures:
4ZGN, 4ZGO, 4ZGP, 4ZGQ - PubMed Abstract:
Eukaryotic initiation factor 2 (eIF2), a heterotrimeric guanosine triphosphatase, has a central role in protein biosynthesis by supplying methionylated initiator tRNA to the ribosomal translation initiation complex and by serving as a target for translational control in response to stress. Recent work identified a novel step indispensable for eIF2 function: assembly of eIF2 from its three subunits by the cell proliferation protein Cdc123. We report the first crystal structure of a Cdc123 representative, that from Schizosaccharomyces pombe, both isolated and bound to domain III of Saccharomyces cerevisiae eIF2γ. The structures show that Cdc123 resembles enzymes of the ATP-grasp family. Indeed, Cdc123 binds ATP-Mg(2+), and conserved residues contacting ATP-Mg(2+) are essential for Cdc123 to support eIF2 assembly and cell viability. A docking of eIF2αγ onto Cdc123, combined with genetic and biochemical experiments, allows us to propose a model explaining how Cdc123 participates in the biogenesis of eIF2 through facilitating assembly of eIF2γ to eIF2α.
Organizational Affiliation:
Laboratoire de Biochimie, Ecole Polytechnique, CNRS, UMR7654, 91128 Palaiseau Cedex, France.
