Related Experiment Video

Updated: Jul 19, 2026

Examination of Proteins Bound to Nascent DNA in Mammalian Cells Using BrdU-ChIP-Slot-Western Technique
09:14

Examination of Proteins Bound to Nascent DNA in Mammalian Cells Using BrdU-ChIP-Slot-Western Technique

Published on: January 14, 2016

Diverse roles for histone H2A modifications in DNA damage response pathways in yeast

John D Moore1, Oya Yazgan, Yeganeh Ataian

  • 1Department of Biological Sciences, University of Alaska, Anchorage, Alaska 99508, USA.

Genetics
|October 10, 2006
PubMed

Insights

Histone H2A modifications in yeast are crucial for DNA repair pathways. Specific patterns of H2A tail modifications act as "damage codes" to direct repair processes for various DNA lesions.

Area of Science:

  • Molecular Biology
  • Genetics
  • Biochemistry

Background:

  • DNA damage is repaired by multiple pathways within the chromatin context.
  • Histone modifications play a role in DNA repair processes.

Purpose of the Study:

  • To investigate the role of histone H2A modifications in DNA repair pathways.
  • To identify specific H2A residues and their modifications involved in repair.

Main Methods:

  • Mutagenesis of modifiable residues in yeast H2A N- and C-terminal tails.
  • Assessing mutant strains in DNA repair assays (homologous recombination, nonhomologous end-joining, UV, oxidative damage).
  • Analyzing H2A phosphorylation patterns.

Main Results:

  • H2A tail residues are essential for double-strand break repair (homologous recombination and nonhomologous end-joining) and survival from UV/oxidative damage.
  • H2A serine 122 is critical for repair and survival across multiple assays.
  • Distinct patterns of H2A phosphorylation at S122, T126, and S129 were observed under different damage conditions.
  • Overlapping but non-identical H2A residue groups participate in different repair pathways.

Conclusions:

  • H2A tail modifications function as "damage codes" to signal specific DNA damage types.
  • These codes may direct the recruitment or activity of specific DNA repair pathways.
  • Histone H2A acts as a central regulator in the DNA damage response.

More Related Videos

Quantification of γH2AX Foci in Response to Ionising Radiation06:53

Quantification of γH2AX Foci in Response to Ionising Radiation

Published on: April 6, 2010

Targeted in Situ Mutagenesis of Histone Genes in Budding Yeast08:48

Targeted in Situ Mutagenesis of Histone Genes in Budding Yeast

Published on: January 26, 2017

Related Concept Videos

Histone Modification02:32

Histone Modification

The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Histone Modification02:32

Histone Modification

The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
DNA Damage can Stall the Cell Cycle02:36

DNA Damage can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
DNA Damage Can Stall the Cell Cycle02:36

DNA Damage Can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
Spreading of Chromatin Modifications02:25

Spreading of Chromatin Modifications

The histone proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are methylation, acetylation, phosphorylation, and ubiquitination of lysine amino acids in the histone H3 tail region. These histone modifications have specific meaning for the cell. Hence, they are called "histone code". The protein complex involved in histone modification is termed as "reader-writer" complex.
Writers
The writer is an enzyme that can...
Histone Variants at the Centromere02:30

Histone Variants at the Centromere

Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3 variants are also...