Photocleavable PROTACs as tools for dynamic regulation of protein function

Area of Science:

• Chemical Biology
• Molecular Biology
• Drug Discovery

Background:

• Proteolysis-targeting chimeras (PROTACs) are powerful tools for targeted protein degradation.
• Conventional PROTACs lack temporal regulation, limiting their use in dynamic biological studies.

Purpose of the Study:

• To develop photocleavable PROTACs for light-inducible temporal control of BET protein degradation.
• To investigate the efficacy and reversibility of these novel PROTACs in cellular systems.

Main Methods:

• Design and synthesis of photocleavable PROTACs utilizing a nitrobenzyl linker.
• Computational docking simulations to assess ternary complex formation.
• Liquid chromatography-tandem mass spectrometry (LC-MS/MS) for photocleavage analysis.
• Cellular assays to evaluate BET protein degradation and recovery after UV irradiation.

Main Results:

• The nitrobenzyl linker did not impede ternary complex formation.
• Rapid photocleavage of the PROTACs was observed within cells.
• Efficient degradation of BET proteins was achieved at low compound concentrations.
• UV irradiation successfully restored protein expression following transient depletion.

Conclusions:

• Photocleavable PROTACs provide a practical method for temporally controlled protein degradation.
• These compounds serve as valuable chemical biology tools for studying dynamic protein functions, particularly for BET proteins.
• The light-triggered reversibility offers precise control over degradation processes.