Related Experiment Video
Updated: Feb 5, 2026
Efficient iPS Cell Generation from Blood Using Episomes and HDAC Inhibitors
Published on: October 28, 2014
INFLUENCE OF HDAC INHIBITOR SODIUM BUTYRATE ON THE EXPRESSION OF DNA REPAIR GENES Rad51 AND XRCC5 IN mEras-Waf1+/+
Abstract:
Mouse embryonal fibroblasts with knockout of CDKN1A gene encoding p21/Waf1 protein transformed by oncogenes E1A and cHa-ras (mEras-Waf1–/– cell line) have been used to assess the level of DNA repair genes expression — Rad51 and XRCC5 after treatment with HDAC inhibitor sodium butyrate as compared with their control counterparts (mEras-Waf1+/+ cells). mEras-Waf1–/– cells are characterized by the elevated amount of single-stranded DNA breaks and g-H2A.X histone foci associated with these breaks. According to immunofluorescence and immunobloting data, Rad51 and Ku80 proteins are highly expressed in the nuclei of both studied cell lines. The level of Ku80 is higher in cells with CDKN1A gene knockout. When cells were treated with DNA-damaging agent adriamycin, there was an additional accumulation of Rad51 foci in the nuclei. However, sodium butyrate reduced considerably the content of Rad51 and Ku80 proteins both in mEras-Waf1+/+ and mEras-Waf1–/– cells as well as in the cells treated by adriamycin. RT-PCR and immunobloting data show that inhibitory effect of sodium butyrate takes place at the level of Rad51 and XRCC5 gene transcription and the content of Rad51 and Ku80 proteins. The observed suppressive effect of HDACI on DNA repair components explains in part the mechanisms of antiproliferative function of HDAC inhibitors. Surprisingly, sodium butyrate was shown to activate the pluripotent genes transcription in mEras-Waf1+/+ and mEras-Waf1–/– cells, as exemplified by upregulation of Oct-4, Sox-2, Klf4, implying that these pluripotent genes are under negative control at the level of chromatin structure.
Insights
Sodium butyrate, an HDAC inhibitor, suppresses DNA repair genes Rad51 and XRCC5 expression and protein levels in mouse cells. This HDAC inhibitor also unexpectedly activates pluripotent gene transcription, revealing new insights into its antiproliferative mechanisms.
Area of Science:
- Molecular Biology
- Cell Biology
- Cancer Research
Background:
- CDKN1A gene knockout in mouse cells leads to increased DNA damage.
- Rad51 and Ku80 proteins are key in DNA repair and are highly expressed in these cells.
- HDAC inhibitors are known for their antiproliferative effects.
Purpose of the Study:
- To investigate the effect of sodium butyrate, an HDAC inhibitor, on DNA repair gene expression (Rad51, XRCC5) in mouse cells with and without CDKN1A.
- To explore the impact of sodium butyrate on DNA repair protein levels and pluripotent gene transcription.
Main Methods:
- Utilized mouse embryonal fibroblasts with and without CDKN1A knockout (mEras-Waf1–/– and mEras-Waf1+/+).
- Treated cells with sodium butyrate and adriamycin (DNA-damaging agent).
- Assessed gene expression via RT-PCR and protein levels/localization via immunofluorescence and immunoblotting.
Main Results:
- Sodium butyrate significantly reduced Rad51 and Ku80 protein and gene expression in both cell types.
- Adriamycin treatment increased Rad51 foci, but sodium butyrate counteracted this effect.
- Sodium butyrate upregulated pluripotent genes (Oct-4, Sox-2, Klf4) in both cell lines.
Conclusions:
- HDAC inhibition by sodium butyrate suppresses DNA repair components, contributing to its antiproliferative function.
- Sodium butyrate activates pluripotent gene transcription, suggesting chromatin-level negative control.
- These findings offer a deeper understanding of HDAC inhibitor mechanisms in cellular processes.
Related Concept Videos
02:25Overview of DNA Repair
Chemically...
02:25Overview of DNA Repair
01:42What is Gene Expression?
Gene expression is the process in which DNA directs the synthesis of functional products, that is, proteins. Cells can regulate gene expression at various stages. It allows organisms to generate different cell types and enables cells to adapt to internal and external factors.
Genetic Information Flows from DNA to RNA to Protein
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is made up of nucleotides and proteins consist of amino...
01:36What is Gene Expression?
01:58Cell Specific Gene Expression
02:35Chromatin Position Affects Gene Expression
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the...