Related Experiment Video
Updated: Feb 24, 2026

Author Spotlight: Efficient Nucleosome Reconstitution for Single-Molecule Techniques
Published on: September 6, 2024
Unfolding of core nucleosomes by PARP-1 revealed by spFRET microscopy
Daniel C Sultanov1,2, Nadezhda S Gerasimova1, Kseniya S Kudryashova1,3
1Biology Faculty, Lomonosov Moscow State University, Moscow, 119992, Russia.
Abstract:
DNA accessibility to various protein complexes is essential for various processes in the cell and is affected by nucleosome structure and dynamics. Protein factor PARP-1 (poly(ADP-ribose)polymerase 1) increases the accessibility of DNA in chromatin to repair proteins and transcriptional machinery, but the mechanism and extent of this chromatin reorganization are unknown. Here we report on the effects of PARP-1 on single nucleosomes revealed by spFRET (single-particle Förster Resonance Energy Transfer) microscopy. PARP-1 binding to a double-strand break in the vicinity of a nucleosome results in a significant increase of the distance between the adjacent gyres of nucleosomal DNA. This partial uncoiling of the entire nucleosomal DNA occurs without apparent loss of histones and is reversed after poly(ADP)-ribosylation of PARP-1. Thus PARP-1-nucleosome interactions result in reversible, partial uncoiling of the entire nucleosomal DNA.
More Related Videos
Related Concept Videos
Nucleosome Remodeling
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
The Nucleosome Core Particle
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
The Nucleosome Core Particle
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
The Nucleosome
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
The Nucleosome
The Nucleosome
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...

