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Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations
Published on: September 20, 2019
Extra centrosomes and/or chromosomes prolong mitosis in human cells
Zhenye Yang1, Jadranka Loncarek, Alexey Khodjakov
1Division of Molecular Medicine, Wadsworth Center, N.Y.S. Department of Health, Empire State Plaza, Albany, New York 12201-0509, USA.
Nature Cell Biology
|May 13, 2008
Summary
Extra centrosomes and chromosomes significantly prolong mitosis in human cells by delaying the spindle assembly checkpoint. This finding suggests non-genetic factors contribute to elevated mitotic indices in tumors.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Mitosis is a fundamental process for cell division.
- The duration of mitosis is tightly regulated.
- Aberrant mitotic progression is linked to diseases like cancer.
Purpose of the Study:
- To investigate the impact of additional centrosomes and chromosomes on mitotic duration in human cells.
- To elucidate the underlying mechanisms by which these factors influence mitosis.
- To explore the relevance of these findings to tumor biology.
Main Methods:
- Laser microsurgery was employed to manipulate cellular components.
- Cell fusion techniques were utilized to introduce extra genetic material and centrosomes.
- Mitotic duration was precisely measured and analyzed.
Main Results:
- Doubling chromosome number increased mitotic duration by approximately 10 minutes.
- Doubling centrosome number increased mitotic duration by approximately 30 minutes.
- Both extra centrosomes and chromosomes delayed the satisfaction of the spindle assembly checkpoint, prolonging mitosis.
Conclusions:
- Mitosis duration can be extended through non-genetic alterations.
- Extra centrosomes and chromosomes contribute to prolonged mitosis by interfering with cell cycle checkpoints.
- These findings offer insights into the elevated mitotic index observed in various tumors.
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To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
02:25Centrosome Duplication
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To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
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