The Molecular Mechanism of Eukaryotic Elongation Factor 2 Kinase Activation

Tavares, Clint D.J.; Ferguson, Scarlett B.; Giles, David K.; Wang, Qiantao; Wellmann, Rebecca M.; O’Brien, John P.; Warthaka, Mangalika; Brodbelt, Jennifer S.; Ren, Pengyu; Dalby, Kevin N.

doi:10.1074/jbc.m114.577148

Cited by 33 publications

(70 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cell-based assays utilizing knockout MCF-10A (eEF-2K −/− ) cells (Sigma-Aldrich) were transfected with vectors encoding wild-type eEF-2K or the W85S mutant and lysed cells were analyzed by Western blotting using eEF-2K, eEF-2 or pT56-eEF-2 specific antibodies (Tavares et al, 2014). Details are provided in the Supplemental Experimental Procedures.…”

Section: Methodsmentioning

confidence: 99%

“…al demonstrated that eEF-2K is activated through a unique two-step process initiated by the binding of Ca 2+ -loaded calmodulin (CaM) (Tavares et al, 2014). This mode of activation does not appear to occur through a “release of inhibition” mechanism (Soderling and Stull, 2001; Swulius and Waxham, 2008) and sets eEF-2K apart from other CaM-dependent kinases.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Structural Basis for the Recognition of Eukaryotic Elongation Factor 2 Kinase by Calmodulin

et al. 2016

View full text Add to dashboard Cite

SUMMARY Binding of Ca2+-loaded calmodulin (CaM) activates eukaryotic elongation factor 2 kinase (eEF-2K) that phosphorylates eEF-2, its only known cellular target, leading to a decrease in global protein synthesis. Here, using an eEF-2K-derived peptide (eEF-2KCBD) that encodes the region necessary for its CaM-mediated activation, we provide a structural basis for their interaction. The striking feature of this association is the absence of Ca2+ from the CaM C-lobe sites, even under high Ca2+ conditions. eEF-2KCBD engages CaM largely through the C-lobe of the latter in an anti-parallel 1-5-8 hydrophobic mode reinforced by a pair of unique electrostatic contacts. Sparse interactions of eEF-2KCBD with the CaM N-lobe results in persisting inter-lobe mobility. A conserved eEF-2K residue (W85) anchors it to CaM by inserting into a deep hydrophobic cavity within the CaM C-lobe. Mutation of this residue (W85S) substantially weakens interactions between full-length eEF-2K and CaM in vitro and reduces eEF-2 phosphorylation in cells.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Structural Basis for the Recognition of Eukaryotic Elongation Factor 2 Kinase by Calmodulin

et al. 2016

View full text Add to dashboard Cite

show abstract

“…This site can even be phosphorylated in E coli, which lacks CaM, suggesting that the activity of eEF2K in autophosphorylation is not strictly Ca/CaM dependent [13] . However, it is stimulated by Ca/CaM [13,14] . The conformational change associated with the phosphorylation of Thr-348 enhances eEF2K activity by increasing its affinity for a (peptide) substrate and its intrinsic catalytic activity.…”

Section: Overview Of the Structure And Control Of Eef2kmentioning

confidence: 99%

Eukaryotic elongation factor 2 kinase as a drug target in cancer, and in cardiovascular and neurodegenerative diseases

Proud

2016

Acta Pharmacol Sin

View full text Add to dashboard Cite

Eukaryotic elongation factor 2 kinase (eEF2K) is an unusual protein kinase that regulates the elongation stage of protein synthesis by phosphorylating and inhibiting its only known substrate, eEF2. Elongation is a highly energy-consuming process, and eEF2K activity is tightly regulated by several signaling pathways. Regulating translation elongation can modulate the cellular energy demand and may also control the expression of specific proteins. Growing evidence links eEF2K to a range of human diseases, including cardiovascular conditions (atherosclerosis, via macrophage survival) and pulmonary arterial hypertension, as well as solid tumors, where eEF2K appears to play contrasting roles depending on tumor type and stage. eEF2K is also involved in neurological disorders and may be a valuable target in treating depression and certain neurodegenerative diseases. Because eEF2K is not required for mammalian development or cell viability, inhibiting its function may not elicit serious side effects, while the fact that it is an atypical kinase and quite distinct from the vast majority of other mammalian kinases suggests the possibility to develop it into compounds that inhibit eEF2K without affecting other important protein kinases. Further research is needed to explore these possibilities and there is an urgent need to identify and characterize potent and specific small-molecule inhibitors of eEF2K. In this article we review the recent evidence concerning the role of eEF2K in human diseases as well as the progress in developing small-molecule inhibitors of this enzyme.

show abstract

“…Two important elongation regulatory factors are eukaryotic elongation factor 2 (eEF2) and its kinase, eEF2K. Eukaryotic elongation factor 2 kinase (eEF2K) is a Ca 2+ /calmodulin (CaM)-dependent kinase, which negatively modulates protein synthesis by phosphorylating eEF2 (Kenney et al, 2014; Tavares et al, 2014). Phosphorylation at Thr56 within the GTP-binding domain of eEF2 prevents its recruitment to ribosomes and thus blocks elongation (Carlberg et al, 1990).…”

Section: Introductionmentioning

confidence: 99%

Crosstalk between eIF2α and eEF2 phosphorylation pathways optimizes translational arrest in response to oxidative stress

Sanchez

Lin

Yang

et al. 2019

Preprint

View full text Add to dashboard Cite

The cellular stress response triggers a cascade of events leading to transcriptional reprogramming and a transient inhibition of global protein synthesis, which is thought to be mediated by phosphorylation of eukaryotic initiation factor-2α (eIF2α). Using mouse embryonic fibroblasts (MEFs) and the fission yeast S. pombe, we report here that rapid translational arrest and cell survival in response to hydrogen peroxide-induced oxidative stress do not rely on eIF2α kinases and eIF2α phosphorylation. Rather H 2 O 2 induces a block in elongation through phosphorylation of eukaryotic elongation factor 2 (eEF2).Kinetic and dose-response analyses uncovered crosstalk between the eIF2α and eEF2 phosphorylation pathways, indicating that, in MEFs, eEF2 phosphorylation initiates the acute shutdown in translation, which is then maintained by eIF2α phosphorylation. Our results challenge the common conception that eIF2α phosphorylation is the primary trigger of translational arrest in response to oxidative stress and point to integrated control that may facilitate the survival of cancer cells. HIGHLIGHTS:• Oxidative stress-induced translation arrest is independent of eIF2α phosphorylation • Oxidative stress blocks translation elongation • Oxidative stress triggers eEF2 kinase activation • eEF2K KO cells are hypersensitive to oxidative stress

show abstract

The Molecular Mechanism of Eukaryotic Elongation Factor 2 Kinase Activation

Cited by 33 publications

References 60 publications

Structural Basis for the Recognition of Eukaryotic Elongation Factor 2 Kinase by Calmodulin

Structural Basis for the Recognition of Eukaryotic Elongation Factor 2 Kinase by Calmodulin

Eukaryotic elongation factor 2 kinase as a drug target in cancer, and in cardiovascular and neurodegenerative diseases

Crosstalk between eIF2α and eEF2 phosphorylation pathways optimizes translational arrest in response to oxidative stress

Contact Info

Product

Resources

About