Related Experiment Video
Updated: Jan 3, 2026
Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells
Published on: May 1, 2020
Multifunnel Energy Landscapes for Phosphorylated Translation Repressor 4E-BP2 and Its Mutants
Wei Kang1,2,3, Fan Jiang1, Yun-Dong Wu1,2
1Laboratory of Computational Chemistry and Drug Design, Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Shenzhen 518055 , China.
Abstract:
Upon phosphorylation of specific sites, eukaryotic translation initiation factor 4E (eIF4E) binding protein 2 (4E-BP2) undergoes a fundamental structural transformation from a disordered state to a four-stranded β-sheet, leading to decreased binding affinity for its partner. This change reflects the significant effects of phosphate groups on the underlying energy landscapes of proteins. In this study, we combine high-temperature molecular dynamics simulations and discrete path sampling to construct energy landscapes for a doubly phosphorylated 4E-BP218-62 and two mutants (a single site mutant D33K and a double mutant Y54A/L59A). The potential and free energy landscapes for these three systems are multifunneled with the folded state and several alternative states lying close in energy, suggesting perhaps a multifunneled and multifunctional protein. Hydrogen bonds between phosphate groups and other residues not only stabilize these low-lying conformations to different extents but also play an important role in interstate transitions. From the energy landscape perspective, our results explain some interesting experimental observations, including the low stability of doubly phosphorylated 4E-BP2 and its moderate binding to eIF4E and the inability of phosphorylated Y54A/L59A to fold.
Insights
Phosphorylation transforms the 4E-BP2 protein structure, altering its function. Energy landscape analysis reveals how this, and mutations, affect protein stability and interactions.
Area of Science:
- Biochemistry
- Structural Biology
- Computational Biology
Background:
- Eukaryotic translation initiation factor 4E (eIF4E) binding protein 2 (4E-BP2) undergoes significant structural changes upon phosphorylation.
- These changes impact protein-protein interactions and cellular processes.
- Understanding these dynamics is crucial for deciphering regulatory mechanisms.
Purpose of the Study:
- To investigate the energy landscapes of doubly phosphorylated 4E-BP2 and its mutants.
- To elucidate the role of phosphorylation and specific mutations in protein structural transitions.
- To explain experimental observations regarding 4E-BP2 stability and binding affinity.
Main Methods:
- High-temperature molecular dynamics simulations.
- Discrete path sampling techniques.
- Construction of potential and free energy landscapes.
Main Results:
- The energy landscapes for the studied systems are multifunneled, indicating multiple stable and near-stable conformational states.
- Hydrogen bonds involving phosphate groups are critical for stabilizing conformations and mediating transitions between states.
- The study explains the observed low stability of doubly phosphorylated 4E-BP2 and the folding defect in the Y54A/L59A mutant.
Conclusions:
- Protein phosphorylation can lead to complex energy landscapes, supporting multifunneled and multifunctional protein behavior.
- The findings provide a molecular-level understanding of how post-translational modifications influence protein structure and function.
- This work bridges computational modeling with experimental data to explain protein dynamics.
