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Histone N-tails modulate sequence-specific positioning of nucleosomes
Tatiana Nikitina1, Wilfried M Guiblet1, Feng Cui2
1National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, US.
Biorxiv : the Preprint Server for Biology
|December 11, 2023
Summary
Histone N-tails significantly influence where nucleosomes bind on DNA. Removing these tails alters DNA sequence preferences and nucleosome positioning, impacting epigenetic regulation.
Area of Science:
- Molecular Biology
- Epigenetics
- Genomics
Background:
- Nucleosome positioning is crucial for DNA accessibility and gene regulation.
- Current models predict only 65% of in vivo nucleosome positions, indicating missing factors.
Approach:
- Reconstituted H2A/H4 tailless nucleosomes on human BRCA1 DNA.
- Compared positions and sequences of tailless vs. wild-type nucleosomes.
Key Points:
- H2A tailless nucleosomes showed local AT content changes at SHL ±4, retaining rotational setting.
- H4 tailless nucleosomes exhibited widespread AT content changes near SHL ±1/±2.
- Many H4 tailless nucleosomes reversed their rotational setting compared to wild-type.
Conclusions:
- Histone N-tails actively select nucleosome positions on DNA.
- N-tail involvement in positioning has broad implications for epigenetic control of chromatin states.
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