Related Experiment Video

Updated: Jul 10, 2025

Deciphering the Structural Effects of Activating EGFR Somatic Mutations with Molecular Dynamics Simulation
15:05

Deciphering the Structural Effects of Activating EGFR Somatic Mutations with Molecular Dynamics Simulation

Published on: May 20, 2020

8.6K

Conformational Stability of the N-Terminal Region of MDM2

Bruno Rizzuti1,2, Olga Abian2,3,4,5, Adrián Velazquez-Campoy2,3,4,5

  • 1CNR-NANOTEC, SS Rende (CS), Department of Physics, University of Calabria, 87036 Rende, Italy.

Molecules (Basel, Switzerland)
|November 25, 2023
PubMed

Insights

The N-terminal region of MDM2 (N-MDM2), crucial for binding the tumor suppressor p53, exhibits low conformational stability and unfolds via multiple intermediates, suggesting inherent flexibility.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Structural Biology

Background:

  • MDM2 is an E3 ubiquitin ligase that targets the tumor suppressor p53 for degradation.
  • The N-terminal region of MDM2 (N-MDM2) mediates interactions with p53 and other protein partners.
  • Understanding N-MDM2's stability and conformational dynamics is key to its function.

Purpose of the Study:

  • To investigate the conformational stability and unfolding pathways of the isolated N-MDM2 domain.
  • To characterize the structural features influencing N-MDM2's interactions with its binding partners.

Main Methods:

  • Intrinsic and 8-anilinonapthalene-1-sulfonic acid (ANS) fluorescence spectroscopy.
  • Far-UV circular dichroism (CD) spectroscopy.
  • Size exclusion chromatography (SEC).
  • Guanidinium chloride (GdmCl) denaturation studies.
  • Differential scanning calorimetry (DSC).
  • Thermo-fluorescence experiments.
  • Computational constraint network analysis (CNA).

Main Results:

  • Isolated N-MDM2 demonstrates native-like stability within a narrow pH range (7.0-10.0).
  • GdmCl denaturation revealed low overall conformational stability for N-MDM2 at physiological pH.
  • Unfolding occurs through a series of intermediate states, indicating a complex pathway.
  • DSC and CNA simulations confirmed a hierarchy of unfolding intermediates.

Conclusions:

  • N-MDM2 possesses intrinsically low conformational stability, attributed to its inherent flexibility.
  • The protein's flexibility facilitates interactions with multiple molecular partners via diverse binding routes.
  • These findings provide insights into the regulatory mechanisms of p53 degradation and MDM2 function.
Keywords:
MDM2circular dichroismconformational stabilityconstraint network analysisdifferential scanning calorimetryfluorescenceintrinsically disordered protein

More Related Videos

Investigating Protein Sequence-structure-dynamics Relationships with Bio3D-web09:51

Investigating Protein Sequence-structure-dynamics Relationships with Bio3D-web

Published on: July 16, 2017

15.5K
CD Spectroscopy to Study DNA-Protein Interactions06:48

CD Spectroscopy to Study DNA-Protein Interactions

Published on: February 10, 2022

6.8K

Related Concept Videos

Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the...
4.5K
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution00:52

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution

At room temperature, the chair conformer of cyclohexane undergoes rapid ring flipping between two equivalent chair conformers at a rate of approximately 105 times per second. These two chair conformers are in equilibrium. The rapid ring flipping results in the interconversion of the axial proton to an equatorial proton and an equatorial to the axial proton. Such interconversions are too rapid and cannot be detected on the NMR timescale. Hence, the NMR spectrometer cannot distinguish between the...
852
Protein Folding01:22

Protein Folding

Overview
118.2K
Microtubule Instability02:17

Microtubule Instability

Microtubules are hollow cylindrical filaments having a diameter of approximately 25 nm and a length that varies from 200 nm to 25 μm. GTP-bound tubulin subunits form αβ-heterodimers for microtubule assembly. These core building blocks interact longitudinally, polymerizing into protofilaments. The protofilaments then interact with one another through lateral bonding forces to form stable cylindrical microtubules. These cylindrical filaments are dynamic as they undergo repeated...
5.1K
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR01:15

¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR

The axial and equatorial protons in cyclohexane can be distinguished by performing a variable-temperature NMR experiment. In this process, except for one proton, the remaining eleven protons are replaced by deuterium. The deuterium substitution avoids the possible peak splitting caused by the spin-spin coupling between the adjacent protons. The remaining proton flips between the axial and equatorial positions.
1.1K
Conserved Binding Sites01:49

Conserved Binding Sites

Many proteins’ biological role depends on their interactions with their ligands, small molecules that bind to specific locations on the protein known as ligand-binding sites. Ligand-binding sites are often conserved among homologous proteins as these sites are critical for protein function.
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally...
4.2K