Related Experiment Videos
DNAase I and cellular factors that affect chromatin structure
Biochimica Et Biophysica Acta
|December 22, 1983
Summary
Standardized DNAase I digestion reveals distinct chromatin structures in G1 and S-phase cells. These cell cycle differences are mediated by diffusible cytoplasmic and nuclear factors, making DNAase I a sensitive probe for chromatin changes.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- DNAase I is a common probe for chromatin structure but often yields irreproducible results.
- Previous work standardized DNAase I digestion for reliable chromatin analysis.
Purpose of the Study:
- To detect differences in chromatin structure between G1 and early S-phase cells.
- To investigate the role of diffusible factors in cell cycle-specific chromatin modifications.
Main Methods:
- Standardized DNAase I digestion assay.
- Cell cycle synchronization using isoleucine deprivation and hydroxyurea.
- Analysis of chromatin accessibility to DNAase I.
Main Results:
- G1-phase cells exhibit easily digestible chromatin, while early S-phase cells show resistant chromatin.
- Diffusible cytoplasmic factors in G1 cells enhance chromatin digestibility.
- Nuclear factors in S-phase cells increase chromatin resistance.
Conclusions:
- DNAase I, under standardized conditions, is a sensitive probe for cell cycle-specific chromatin structural changes.
- Diffusible factors play a key role in modulating chromatin structure during the cell cycle.
- This method can be applied to study differentiation, development, hormone action, and chemical toxicity.