Related Experiment Video
Updated: Aug 15, 2026
08:16
In Vitro Characterization of Histone Chaperones using Analytical, Pull-Down and Chaperoning Assays
Published on: December 29, 2021
In and out: histone variant exchange in chromatin
Jingji Jin1, Yong Cai, Bing Li
1Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA.
Trends in Biochemical Sciences
|November 1, 2005
Summary
Histone variants, unlike canonical histones, are incorporated independently of DNA replication. These variants are deposited by specific protein complexes, influencing chromatin structure and epigenetic regulation.
Area of Science:
- Molecular Biology
- Epigenetics
- Chromatin Biology
Background:
- Nucleosome structure alterations impact DNA accessibility and create specialized chromatin domains.
- Histone modifications, chromatin remodeling, and histone variant incorporation are key mechanisms for these alterations.
- Histone variants (e.g., H2A, H3 variants) are incorporated independently of DNA replication, unlike canonical histones.
Purpose of the Study:
- To summarize the mechanisms and consequences of histone variant incorporation into nucleosomes.
- To highlight the role of specific multiprotein complexes in targeted histone variant deposition.
- To underscore the epigenetic significance of histone variants in chromatin architecture.
Main Methods:
- Review of recent studies on histone variant deposition.
- Analysis of multiprotein complexes involved in histone variant targeting.
- Examination of the relationship between histone variants and chromatin structure.
Main Results:
- Distinct multiprotein complexes mediate the targeted deposition of histone variants.
- Histone variant incorporation occurs at active genes, centromeres, and silent loci.
- Histone variant deposition is independent of the DNA replication S phase.
Conclusions:
- Histone variant incorporation is a replication-independent process.
- Specialized protein complexes ensure precise localization of histone variants.
- Histone variants contribute to epigenetic modifications and chromosomal architectural changes.
More Related Videos
07:41Sequential Salt Extractions for the Analysis of Bulk Chromatin Binding Properties of Chromatin Modifying Complexes
Published on: October 2, 2017
11:02Complete Workflow for Analysis of Histone Post-translational Modifications Using Bottom-up Mass Spectrometry: From Histone Extraction to Data Analysis
Published on: May 17, 2016
Related Concept Videos
02:32Histone 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,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
02:32Histone 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,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
02:25Spreading 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...
Writers
The writer is an enzyme that can...
02:32Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
03:17Inheritance of Chromatin Structures
Epigenetics is the study of inherited changes in a cell's phenotype without changing the DNA sequences. It provides a form of memory for the differential gene expression pattern to maintain cell lineage, position-effect variegation, dosage compensation, and maintenance of chromatin structures such as telomeres and centromeres. For example, the structure and location of the centromere on chromosomes are epigenetically inherited. Its functionality is not dictated or ensured by the underlying DNA...
01:01Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...