Protocol for quantifying PARP inhibitor-induced changes in PARP1 dynamics and activity through live-cell imaging.

Area of Science:

• Molecular Biology
• Cell Biology
• Biochemistry

Background:

• Poly(ADP-ribose) polymerase 1 (PARP1) is vital for DNA repair.
• PARP inhibitors (PARPi) target PARP1's catalytic activity and chromatin association.
• Understanding DNA repair dynamics is crucial for drug development.

Purpose of the Study:

• To present a live-cell imaging protocol for studying DNA repair kinetics.
• To visualize fluorescently labeled PARP1 and poly(ADP-ribose) (PAR)-binding proteins.
• To investigate the impact of PARP inhibitors on DNA repair protein dynamics.

Main Methods:

• Developed a live-cell imaging protocol.
• Utilized micro-irradiation to induce DNA damage sites.
• Tracked kinetics of fluorescently labeled PARP1 and PAR-binding proteins.
• Examined protein behavior in both untreated and PARPi-treated cells.

Main Results:

• Achieved high-quality kinetic data of PARP1 and PAR-binding proteins at damage sites.
• Demonstrated the protocol's ability to capture dynamic changes in protein association with chromatin.
• Provided insights into the effects of PARPi on DNA repair protein localization and dynamics.

Conclusions:

• The presented live-cell imaging protocol enables detailed kinetic analysis of DNA repair proteins.
• This method is adaptable for studying other DNA repair proteins and drug mechanisms.
• Facilitates a deeper understanding of DNA repair pathways and the action of DNA repair-targeting drugs.