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Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Cell cycle regulation of PML modification and ND10 composition
R D Everett1, P Lomonte, T Sternsdorf
1MRC Virology Unit, Church Street, Glasgow G11 5JR, Scotland, UK. r.everett@vir.gla.ac.uk
Journal of Cell Science
|November 27, 1999
Summary
Nuclear bodies (PML nuclear bodies) undergo significant biochemical changes during the cell cycle, involving SUMO-1 conjugation and de-conjugation, impacting their structure and function.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Nuclear bodies (PML nuclear bodies) are dynamic sub-structures involved in cellular processes.
- Their structural changes correlate with cellular transformation and viral infection.
Purpose of the Study:
- To investigate the biochemical modifications of ND10 components (PML and Sp100) during the cell cycle.
- To elucidate the role of phosphorylation in PML modification and ND10 structure.
Main Methods:
- Analysis of PML and Sp100 protein conjugation and de-conjugation.
- In vitro stability assays of PML isoforms.
- Treatment with phosphatase inhibitors and heat shock.
- Immunofluorescence microscopy to assess co-localization and structural changes.
Main Results:
- PML and Sp100 are SUMO-1 conjugated during interphase and de-conjugated during mitosis.
- A distinct, labile PML isoform appears during mitosis, stabilized by phosphatase inhibitors.
- Phosphatase inhibition in interphase cells mimics the mitotic PML isoform.
- PML and Sp100 co-localization is disrupted during mitosis and upon cellular stress.
Conclusions:
- Phosphorylation plays a key role in differential PML modification during the cell cycle.
- Cell cycle-dependent biochemical mechanisms likely govern ND10 structural dynamics.
- External stimuli modifying ND10 structure may act via these cell cycle-related biochemical pathways.
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