Related Experiment Video
Updated: Jun 10, 2026

Assays for Validating Histone Acetyltransferase Inhibitors
Published on: August 6, 2020
Inhibition of mitotic-specific histone phosphorylation by sodium arsenite
J M Cobo1, J G Valdez, L R Gurley
1Dpto. Nutricion y Bromatologia, Facultad de Farmacia, Universidad de Alcala de Henares, Alcala de Henares, 28871 Madrid, Spain.
Abstract:
Synchronized cultures of Chinese hamster cells (line CHO) were used to measure the effects of 10 mum sodium arsenite on histone phosphorylation. This treatment caused cell proliferation to be temporarily arrested, after which the cells spontaneously resumed cell proliferation in a radiomimetic manner. Immediately following treatment, it was found that sodium arsenite affected only mitotic-specific H1 and H3 phosphorylations. Neither interphase, nor mitotic, H2A and H4 phosphorylations were affected, nor was interphase H1 phosphorylation affected. The phosphorylation of H1 was inhibited only in mitosis, reducing H1 phosphorylation to 38.1% of control levels, which was the level of interphase H1 phosphorylation. The phosphorylation of both H3 variants was inhibited in mitosis, the less hydrophobic H3 to 19% and the more hydrophobic H3 to 24% of control levels. These results suggest that sodium arsenite may inhibit cell proliferation by interfering with the cyclin B/p34(cdc2) histone kinase activity which is thought to play a key role in regulating the cell cycle. It has been proposed that H1 and H3 phosphorylations play a role in restructuring interphase chromatin into metaphase chromosomes. Interference in this process by sodium arsenite may lead to structurally damaged chromosomes, resulting in the increased cancer risks known to be produced by arsenic exposure from the environment.
More Related Videos
08:12Global Level Quantification of Histone Post-Translational Modifications in a 3D Cell Culture Model of Hepatic Tissue
Published on: May 5, 2022
07:21Automated Sample Preparation for the Multiplexed Analysis of Single-Cell Histone Post-Translational Modifications (sc-hPTM2)
Published on: December 19, 2025
Related Concept Videos
Drugs that Destabilize Microtubules
The Spindle Assembly Checkpoint
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Separation of Sister Chromatids
At the onset of anaphase, separase, a proteolytic enzyme, is...
Eukaryotic Transcription Inhibitors
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
Drugs that Stabilize Microtubules
Inhibition of Cdk Activity