Related Experiment Video
Updated: Jan 19, 2026
Deciphering the Structural Effects of Activating EGFR Somatic Mutations with Molecular Dynamics Simulation
Published on: May 20, 2020
Loosening of Side-Chain Packing Associated with Perturbations in Peripheral Dynamics Induced by the D76N Mutation of
Kazumasa Sakurai1, Ryosuke Tomiyama2, Takuma Shiraki3
1High Pressure Protein Research Center, Institute of Advanced Technology, Kindai University, 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan. sakurai@waka.kindai.ac.jp.
Abstract:
β2-Microglobulin (β2m) is the causative protein of dialysis-related amyloidosis, and its D76N variant is less stable and more prone to aggregation. Since their crystal structures are indistinguishable from each other, enhanced amyloidogenicity induced by the mutation may be attributed to changes in the structural dynamics of the molecule. We examined pressure and mutation effects on the β2m molecule by NMR and MD simulations, and found that the mutation induced the loosening of the inter-sheet packing of β2m, which is relevant to destabilization and subsequent amyloidogenicity. On the other hand, this loosening was coupled with perturbed dynamics at some peripheral regions. The key result for this conclusion was that both the mutation and pressure induced similar reductions in the mobility of these residues, suggesting that there is a common mechanism underlying the suppression of inherent fluctuations in the β2m molecule. Analyses of data obtained under high pressure conditions suggested that the network of dynamically correlated residues included not only the mutation site, but also distal residues, such as those of the C- and D-strands. Reductions in these local dynamics correlated with the loosening of inter-sheet packing.
Insights
The D76N mutation in beta2-microglobulin (β2m) loosens its structure, increasing amyloid formation risk. Pressure and mutation similarly affect β2m dynamics, revealing a common mechanism in protein destabilization and amyloidogenicity.
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Beta2-microglobulin (β2m) is implicated in dialysis-related amyloidosis.
- The D76N variant of β2m exhibits reduced stability and increased aggregation propensity.
- Crystal structures of wild-type and mutant β2m are similar, suggesting dynamic changes underlie enhanced amyloidogenicity.
Purpose of the Study:
- To investigate the effects of pressure and the D76N mutation on β2m structural dynamics.
- To elucidate the molecular mechanisms linking β2m structural dynamics to amyloidogenicity.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy.
- Molecular Dynamics (MD) simulations.
- High-pressure studies.
Main Results:
- The D76N mutation causes loosening of inter-sheet packing in β2m, correlating with destabilization and amyloidogenicity.
- Both mutation and pressure reduce the mobility of peripheral residues, indicating a shared mechanism affecting β2m dynamics.
- Dynamically correlated residues, including distal ones like C- and D-strands, are identified, and their reduced dynamics correlate with loosened inter-sheet packing.
Conclusions:
- The D76N mutation destabilizes β2m by loosening inter-sheet packing, contributing to amyloid formation.
- A common mechanism involving suppressed molecular fluctuations underlies both mutation- and pressure-induced changes in β2m.
- Understanding these dynamic changes is crucial for developing strategies against dialysis-related amyloidosis.
Related Concept Videos
15:05Deciphering the Structural Effects of Activating EGFR Somatic Mutations with Molecular Dynamics Simulation
06:37Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
09:25NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins
05:56Exploring Caspase Mutations and Post-Translational Modification by Molecular Modeling Approaches
08:54Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
12:39Computational Fluid Dynamics Simulations of Blood Flow in a Cerebral Aneurysm
The objective of this video is to describe recent advancements of computational fluid dynamic (CFD) simulations based on patient- or animal-specific vasculature. Here, subject-based vessel segmentations were created, and, using a combination of open-source and commercial tools, a high-resolution numerical solution was determined within a flow...