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Poly(ADP-Ribose) polymerase1 Has Potential to Facilitate the Nucleosome Disassembly
Aleksandr A Alekseev1, Mikhail M Kutuzov2, Ekaterina A Belousova2
1Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia.
International Journal of Molecular Sciences
|August 13, 2026
Summary
Poly(ADP-ribose) polymerase1 (PARP1) binding to nucleosomes weakens DNA contacts. This finding reveals novel insights into how PARP1 influences chromatin structure and genome accessibility.
Area of Science:
- Molecular Biology
- Genetics
- Biophysics
Background:
- Nucleosomes are fundamental chromatin units, and their stability governs genome accessibility.
- Poly(ADP-ribose) polymerase1 (PARP1) is a key DNA-binding protein involved in genome compaction.
- The precise interaction between nucleosomes and PARP1, especially in its non-activated state, is not fully understood.
Purpose of the Study:
- To investigate the effect of PARP1 binding on nucleosome structure and stability.
- To elucidate the mechanism by which PARP1 interacts with nucleosomes at a single-molecule level.
Main Methods:
- Utilized single-molecule optical tweezers to measure forces and dynamics.
- Analyzed the interaction between purified PARP1 and reconstituted nucleosomes.
Main Results:
- Observed significant changes in nucleosome wrapping strength upon PARP1 interaction.
- Demonstrated that PARP1 binding weakens the contacts of the inner DNA turns within the nucleosome.
Conclusions:
- PARP1 binding alters nucleosome structure by reducing DNA contact strength.
- This interaction provides new insights into PARP1's role in regulating chromatin accessibility and genome organization.
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