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Updated: Jun 13, 2026
10:40
Assembly of Nucleosomal Arrays from Recombinant Core Histones and Nucleosome Positioning DNA
Published on: September 10, 2013
Structural insight into the sequence dependence of nucleosome positioning
Bin Wu1, Kareem Mohideen, Dileep Vasudevan
1Division of Structural and Computational Biology, School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
Structure (London, England : 1993)
|April 20, 2010
Summary
Nucleosome positioning is sequence-dependent. Specific DNA sequences like TTTAA, aided by histone proteins, create narrow DNA grooves, influencing genomic regulation.
Area of Science:
- Structural biology
- Genomics
- Molecular biology
Background:
- Nucleosome positioning is crucial for genomic regulation and exhibits sequence-specific characteristics.
- Understanding the structural basis of DNA sequence preference in nucleosome formation is essential.
Purpose of the Study:
- To elucidate the structural mechanisms underlying strong nucleosome positioning sequences.
- To investigate the role of specific DNA elements and histone-DNA interactions in nucleosome core particle formation.
Main Methods:
- X-ray crystallography to determine the structure of nucleosome core particles.
- Analysis of DNA sequence-protein interactions within the nucleosome.
Main Results:
- Solved structures of nucleosome core particles with strong TTTAA positioning elements.
- Identified a histone protein motif forming a 'sugar clamp' that narrows the DNA minor groove at specific sites.
- Demonstrated the TA dinucleotide's role in facilitating DNA bending and compression within the nucleosome.
Conclusions:
- Specific DNA sequences, particularly TTTAA, dictate nucleosome positioning through interactions with histone proteins.
- Histone octamers possess features that favor sequence discrimination, impacting DNA binding and genomic regulation.
- The findings provide insights into the structural underpinnings of sequence-dependent nucleosome organization.
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