Single Molecule FRET: A Powerful Tool to Study Intrinsically Disordered Proteins.

Area of Science:

• Biophysics
• Protein Science
• Molecular Biology

Background:

• Intrinsically disordered proteins (IDPs) exhibit dynamic, random conformational exploration, challenging traditional experimental study.
• Synchronizing random fluctuations in IDP ensembles for observation is experimentally difficult.

Purpose of the Study:

• To address experimental considerations for applying single molecule Förster resonance energy transfer (smFRET) to study IDP configurations.
• To demonstrate smFRET's utility in understanding IDP regulation and function through case studies.

Main Methods:

• Utilizing single molecule Förster resonance energy transfer (smFRET) with high time resolution.
• Analyzing transient populations of sub-states within molecular ensembles of IDPs.

Main Results:

• smFRET can resolve transitions in IDP behaviors and detect phosphorylation-induced modifications.
• Observed modifications altered but did not eliminate disordered properties, impacting biological function.
• Case studies on PAGE4 and a GluN2B NMDA receptor segment highlight smFRET's capabilities.

Conclusions:

• smFRET is a powerful tool for investigating the conformational dynamics of IDPs.
• Understanding IDP ensembles is crucial for elucidating their regulatory mechanisms in biological networks.
• Phosphorylation can modulate IDP function by altering their disordered state ensemble.