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09:14
Examination of Proteins Bound to Nascent DNA in Mammalian Cells Using BrdU-ChIP-Slot-Western Technique
Published on: January 15, 2016
Human protein MCM6 on HeLa cell chromatin
H P Holthoff1, M Baack, A Richter
1Department of Biology, Universität Konstanz, D-78457 Konstanz, Germany.
The Journal of Biological Chemistry
|April 29, 1998
Summary
Researchers identified the sixth human Minichromosome maintenance (MCM6) protein and studied its location within the cell nucleus. MCM6 forms complexes with other MCM proteins and associates with chromatin, suggesting a role in DNA replication regulation.
Area of Science:
- Molecular Biology
- Cell Biology
- Genetics
Background:
- Minichromosome maintenance (Mcm) proteins are crucial for eukaryotic DNA replication.
- Six Mcm proteins are conserved in humans, with MCM6 recently identified.
- Understanding MCM6's role requires investigating its nuclear localization and chromatin association.
Purpose of the Study:
- To determine the intranuclear distribution of the human MCM6 protein.
- To investigate the association of MCM6 with chromatin using micrococcal nuclease.
- To explore the potential monomeric or complex forms of MCM proteins on chromatin.
Main Methods:
- Antibodies specific to MCM6 were used to assess its intranuclear distribution.
- Micrococcal nuclease digestion was employed to study MCM6-chromatin interactions.
- Analysis of protein fractions released by nuclease digestion.
Main Results:
- A fraction of MCM6 protein resides in the nucleosol, forming complexes with other Mcm proteins.
- MCM6 is released from chromatin in multiprotein complexes upon nuclease digestion.
- MCM3 and MCM6 proteins can also be released as monomers, suggesting varied chromatin association.
- Chromatin regions bound by Mcm proteins appear more susceptible to nuclease digestion.
Conclusions:
- MCM6 protein participates in multiprotein complexes with other Mcm proteins within the nucleus.
- MCM6 exhibits association with chromatin, potentially as part of larger complexes or as monomers.
- The differential nuclease sensitivity of Mcm-bound chromatin suggests unique structural properties.
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