Download MendeleyChaperone Function of Hgh1 in the Biogenesis of Eukaryotic Elongation Factor 2.
Monkemeyer, L., Klaips, C.L., Balchin, D., Korner, R., Hartl, F.U., Bracher, A.(2019) Mol Cell 74: 88-100.e9
- PubMed: 30876804
- DOI: https://doi.org/10.1016/j.molcel.2019.01.034
- Primary Citation of Related Structures:
6HB1, 6HB2, 6HB3 - PubMed Abstract:
Eukaryotic elongation factor 2 (eEF2) is an abundant and essential component of the translation machinery. The biogenesis of this 93 kDa multi-domain protein is assisted by the chaperonin TRiC/CCT. Here, we show in yeast cells that the highly conserved protein Hgh1 (FAM203 in humans) is a chaperone that cooperates with TRiC in eEF2 folding. In the absence of Hgh1, a substantial fraction of newly synthesized eEF2 is degraded or aggregates. We solved the crystal structure of Hgh1 and analyzed the interaction of wild-type and mutant Hgh1 with eEF2. These experiments revealed that Hgh1 is an armadillo repeat protein that binds to the dynamic central domain III of eEF2 via a bipartite interface. Hgh1 binding recruits TRiC to the C-terminal eEF2 module and prevents unproductive interactions of domain III, allowing efficient folding of the N-terminal GTPase module. eEF2 folding is completed upon dissociation of TRiC and Hgh1.
Organizational Affiliation:
Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
