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10:36
Chromatin Immunoprecipitation from Human Embryonic Stem Cells
Published on: July 22, 2008
Chromatin remodeling by cell cycle stage-specific extracts from Physarum polycephalum
1Department of Biochemistry and Biophysics, University of Rochester Medical Center, NY/USA. Christophe-Thiriet@urmc.rochester.edu
European Journal of Cell Biology
|April 29, 1999
Summary
Physarum polycephalum cell cycle extracts remodel chromatin differently. S-phase extracts compact chromatin, while late G2-phase extracts increase nuclear volume and DNA accessibility, impacting genetic programs.
Area of Science:
- Cell Biology
- Molecular Biology
- Chromatin Dynamics
Background:
- Chromatin remodeling is crucial for gene regulation.
- Physarum polycephalum offers unique nuclear cell cycle synchrony for research.
Purpose of the Study:
- To investigate how cell cycle stage-specific extracts from Physarum polycephalum influence erythrocyte nuclear chromatin remodeling.
- To identify distinct chromatin changes induced by S-phase and late G2-phase extracts.
Main Methods:
- Utilized whole-cell extracts from synchronized Physarum polycephalum nuclei.
- Assessed nuclear remodeling via microscopy, protamine competition, micrococcal nuclease digestion, and histone H5 release.
- Analyzed in vitro mononucleosome remodeling using DNase I digestion profiles.
Main Results:
- S-phase extracts induced chromatin compaction.
- Late G2-phase extracts increased nuclear volume, DNA accessibility, and linker histone release.
- Late G2 extracts altered the DNase I digestion profile of reconstituted mononucleosomes.
Conclusions:
- Cell cycle progression in Physarum polycephalum is associated with distinct, stage-specific chromatin remodeling activities.
- These findings provide insights into the dynamic regulation of chromatin structure during the cell cycle.
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