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How unfinished business from S-phase affects mitosis and beyond
Hocine W Mankouri1, Diana Huttner, Ian D Hickson
1Department of Cellular and Molecular Medicine, Nordea Center for Healthy Aging, Copenhagen N, Denmark.
The EMBO Journal
|September 26, 2013
Summary
Unresolved chromosomes from S-phase can enter mitosis, risking genome instability. This review explores how cells manage and even utilize these unfinished replication events to maintain DNA stability.
Area of Science:
- Cell Biology
- Genetics
- Molecular Biology
Background:
- The eukaryotic cell cycle is traditionally seen as a series of sequential, discrete steps.
- Emerging evidence indicates that incompletely replicated chromosomes from S-phase can persist into mitosis.
- These unresolved chromosomes pose a risk to accurate sister chromatid segregation.
Purpose of the Study:
- To review the DNA structures arising from "unfinished S-phase business" at various mitotic stages.
- To discuss cellular mechanisms for tolerating these events.
- To explore how cells may exploit these situations for genome stability.
Main Methods:
- Literature review of current research on cell cycle progression and chromosome biology.
- Analysis of cytogenetic data related to DNA structures in mitosis.
- Discussion of molecular mechanisms involved in DNA repair and genome maintenance.
Main Results:
- "Unfinished S-phase business" leads to diverse cytogenetically distinct DNA structures at specific chromosomal loci during mitosis.
- Cells possess mechanisms to tolerate the presence of incompletely replicated chromosomes.
- These persistent structures can be leveraged to enhance genome stability.
Conclusions:
- The persistence of unresolved chromosomes into mitosis is a common occurrence in eukaryotic cells.
- Cellular strategies exist to manage and potentially benefit from these events, contributing to overall genome integrity.
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