Photocontrolled trimethoprim PROTACs targeting the eDHFR protein tag

Area of Science:

• Biochemistry
• Molecular Biology
• Pharmacology

Background:

• Proteolysis Targeting Chimeric Small Molecules (PROTACs) enable targeted protein degradation.
• Spatiotemporal control of PROTAC activity is crucial for therapeutic applications.
• Photopharmacology allows light-mediated spatial control of drug action.

Purpose of the Study:

• To synthesize photocaged and photoswitchable PROTACs for spatiotemporal control.
• To investigate the regulation of E. coli dihydrofolate reductase (eDHFR) tagged proteins in tumor and CAR-T cells.
• To develop light-controlled, tag-directed degraders for precise protein expression modulation.

Main Methods:

• Synthesis of photocaged and photoswitchable PROTAC molecules.
• Testing PROTAC activity on eDHFR-tagged proteins in tumor and CAR-T cells.
• Evaluation of light-mediated regulation of CAR T cell cytotoxicity and cytokine secretion.

Main Results:

• Developed triazole-linked trimethoprim-PROTACs (TMP-TACtz) that degrade eDHFR fused proteins at picomolar concentrations.
• Achieved protein degradation in cells with low cereblon E3 ligase levels with minimal off-target effects.
• Identified a photocleavable compound (TMP-TAC-PC) for optimal light-mediated regulation of CAR T cell functions.

Conclusions:

• Photocontrolled PROTACs offer a novel strategy for spatiotemporal control of protein degradation.
• These photocontrolled, tag-directed degraders can precisely modulate protein expression in targeted cells.
• This approach holds promise for advanced therapeutic applications in oncology and immunotherapy.