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Updated: Jun 2, 2026
08:48
Targeted in Situ Mutagenesis of Histone Genes in Budding Yeast
Published on: January 26, 2017
Genome-wide DNA sequence polymorphisms facilitate nucleosome positioning in yeast
Zhiming Dai1, Xianhua Dai, Qian Xiang
1Department of Electronic, School of Information Science and Technology, Sun Yat-Sen University, Guangzhou 510006, China. zhimdai@gmail.com
Bioinformatics (Oxford, England)
|May 10, 2011
Summary
Sequence polymorphisms in yeast help maintain nucleosome positioning. These genetic variations favor nucleosome formation in nucleosomal DNA and inhibit it in nucleosome-depleted DNA, ensuring genome-wide nucleosome architecture.
Area of Science:
- Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- DNA sequence intrinsically influences nucleosome positioning.
- Specific DNA patterns can either promote or hinder nucleosome formation.
- Nucleosome positioning affects genome-wide sequence evolution rates, but its impact on specific evolutionary patterns remains unclear.
Purpose of the Study:
- Investigate if nucleosomal and nucleosome-depleted DNA exhibit distinct polymorphism patterns.
- Determine if these patterns contribute to maintaining genome-wide nucleosome architecture in yeast.
Main Methods:
- Comparative analysis of sequence polymorphisms in yeast.
- Examination of DNA regions with and without nucleosomes.
- Correlation of polymorphisms with nucleosome formation and positioning stability.
Main Results:
- Sequence polymorphisms in nucleosomal DNA promote nucleosome formation.
- Polymorphisms in nucleosome-depleted DNA inhibit nucleosome formation, particularly at gene ends.
- Polymorphisms that facilitate nucleosome positioning correlate with stable nucleosome positioning.
Conclusions:
- Sequence polymorphisms are under selective pressure to maintain nucleosome positioning.
- These findings reveal a mechanism for preserving nucleosome architecture through genetic variation.
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