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Updated: Aug 4, 2026
10:40
Assembly of Nucleosomal Arrays from Recombinant Core Histones and Nucleosome Positioning DNA
Published on: September 11, 2013
Nucleosome positioning and modification: chromatin structures that potentiate transcription
1Laboratory of Molecular Embryology, National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892.
Trends in Biochemical Sciences
|June 1, 1994
Summary
Positioned nucleosomes do more than just package DNA. They actively regulate gene transcription by controlling access to regulatory DNA sequences, influencing gene expression.
Area of Science:
- Molecular Biology
- Genetics
- Epigenetics
Background:
- The nucleosome, composed of DNA wrapped around histone proteins, is traditionally viewed as a DNA packaging unit.
- Its role in gene regulation, particularly how DNA folds around histones in positioned nucleosomes, is increasingly recognized.
Purpose of the Study:
- To review the active and regulatory roles of positioned nucleosomes in controlling gene transcription.
- To highlight how nucleosome positioning influences transcription factor access and the transcription process.
Main Methods:
- This review synthesizes existing research and specific examples.
- Focuses on the functional implications of nucleosome positioning in gene regulation.
Main Results:
- Positioned nucleosomes play a crucial role beyond simple DNA packaging.
- The precise folding of regulatory gene sequences around histones within nucleosomes is critical for controlling gene expression.
- Specific examples demonstrate an active regulatory function for positioned nucleosomes.
Conclusions:
- Nucleosome positioning is a key epigenetic mechanism influencing gene transcription.
- Understanding nucleosome dynamics is essential for comprehending gene regulation and cellular processes.
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