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Updated: May 28, 2026
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Using Fluorescence In Situ Hybridization (FISH) to Monitor the State of Arm Cohesion in Prometaphase and Metaphase I Drosophila Oocytes
Published on: December 6, 2017
A double lock on sister chromatids by cohesin
1Cell Cycle Group, Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK. luis.aragon@csc.mrc.ac.uk
Molecular Cell
|October 11, 2011
Summary
Sister chromatid intertwining at metaphase is more significant than previously believed. This crucial chromosomal linkage is dependent on the cohesin complex, revealing new insights into cell division.
Area of Science:
- Cell Biology
- Genetics
- Molecular Biology
Background:
- Sister chromatid cohesion is essential for accurate chromosome segregation during cell division.
- The precise mechanisms and extent of sister chromatid interactions at metaphase have been debated.
- Cohesin is a protein complex known to regulate sister chromatid cohesion.
Discussion:
- Farcas et al. (2011) provide compelling evidence for a greater-than-anticipated level of sister chromatid intertwining during metaphase.
- This study reveals that cohesin plays a direct and significant role in establishing and maintaining this intertwining.
- The findings challenge previous assumptions about the spatial arrangement of chromosomes before anaphase.
Key Insights:
- Sister chromatid intertwining is a substantial feature of metaphase chromosomes.
- Cohesin is a critical regulator of sister chromatid intertwining, impacting chromosome structure.
- This intertwining likely contributes to chromosome stability and proper alignment on the metaphase plate.
Outlook:
- Further investigation into how cohesin-mediated intertwining influences chromosome mechanics.
- Exploring the functional implications of this intertwining for preventing aneuploidy.
- Understanding the regulation of intertwining beyond cohesin in different cellular contexts.
Related Concept Videos
02:20Cohesins
Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
02:20Cohesins
Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...