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Updated: Sep 4, 2025
06:39
Live Cell Imaging of Chromosome Segregation During Mitosis
Published on: March 14, 2018
9.5K
Nuclear chromosome locations dictate segregation error frequencies
Sjoerd J Klaasen1, My Anh Truong2, Richard H van Jaarsveld1
1Oncode Institute, Hubrecht Institute-KNAW (Royal Academy of Arts and Sciences) and University Medical Centre Utrecht, Utrecht, the Netherlands.
Nature
|July 13, 2022
Summary
Chromosome position influences chromosome mis-segregation during cell division, leading to non-random aneuploidy. Peripheral chromosomes are more prone to errors, impacting cancer genome evolution and developmental aneuploidies.
Area of Science:
- Cell Biology
- Genetics
- Genomics
Background:
- Chromosome segregation errors during cell division lead to aneuploidies and micronuclei.
- Aneuploidies and chromosomal rearrangements like chromothripsis are hallmarks of cancer and developmental abnormalities.
Purpose of the Study:
- To investigate whether specific chromosomes have inherent biases in segregation errors and micronucleation.
- To understand the relationship between chromosome position, segregation fidelity, and micronucleus formation.
Main Methods:
- Single-cell DNA sequencing of untransformed diploid cell lines and organoids after error-prone mitosis.
- Isolation and sequencing of single micronuclei.
- Live tracking and forced repositioning of individual chromosomes using Cas9 technology.
Main Results:
- Chromosomes exhibit non-random aneuploidy landscapes due to differential segregation error frequencies.
- Mis-segregating chromosomes are preferentially entrapped in micronuclei.
- Chromosome position within the interphase nucleus correlates with segregation error frequency, with peripheral chromosomes being more susceptible.
Conclusions:
- Nuclear chromosome position is a key determinant of segregation error rates.
- Increased distance from the nuclear center elevates the risk of chromosome mis-segregation.
- Findings link nuclear organization to genome instability, with implications for cancer and developmental biology.
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