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Updated: May 15, 2026
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Targeted in Situ Mutagenesis of Histone Genes in Budding Yeast
Published on: January 26, 2017
Conditional allelic replacement applied to genes encoding the histone variant H3.3 in the mouse
Michelle C W Tang1, Shelley A Jacobs, Lee H Wong
1Theme of Genetic Disorders, Murdoch Childrens Research Institute, The Royal Children's Hospital, Victoria, 3052, Australia.
Genesis (New York, N.Y. : 2000)
|January 15, 2013
Summary
Researchers developed new gene targeting vectors to study histone H3.3 in mice. These tools enable conditional replacement of histone H3.3 coding sequences, aiding research into epigenetic modifications in development and disease.
Area of Science:
- Epigenetics
- Molecular Biology
- Genetics
Background:
- Post-translational modifications (PTMs) on core histones are crucial epigenetic regulators.
- Studying the functional impact of PTMs often involves amino acid substitution mutants.
- This approach has not been previously applied to mice for histone variant H3.3.
Purpose of the Study:
- To develop and evaluate gene targeting vectors for Cre recombinase-mediated conditional allelic replacement of histone variant H3.3 in mice.
- To create tools for analyzing the effects of H3.3 deficiency and specific residue modifications in development and disease.
Main Methods:
- Designed conditional gene targeting vectors for the two unlinked H3.3 genes.
- Constructed alleles with wild-type H3.3 coding sequence upstream of a proxy sequence, flanked by loxP sites.
- Demonstrated proof of principle by replacing wild-type H3.3 with a fluorescent reporter to create null alleles.
Main Results:
- Successfully generated gene targeting vectors for conditional allelic replacement of H3.3.
- Created H3.3 null alleles using a fluorescent reporter, suitable for studying H3.3 deficiency.
- The developed vectors are adaptable for introducing modified H3.3 proteins.
Conclusions:
- The developed vectors provide a powerful new system for conditional substitution of H3.3 residues in mice.
- This methodology will facilitate the dissection of H3.3 PTM roles in biological processes and disease pathogenesis.
- Enables detailed investigation into epigenetic information conveyed by histone modifications.
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