Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Forces Acting on Chromosomes02:11

Forces Acting on Chromosomes

3.3K
During mitosis, chromosome movements occur through the interplay of multiple piconewton level forces. In prometaphase, these forces help in chromosome assembly or congression at the equatorial plane, eventually leading to their alignment at the metaphase plate. The forces acting on the chromosomes are space and time-dependent; therefore, they vary with the position of the chromosomes as the cell progresses through mitosis. 
Microtubules and motor proteins exert two types of forces on...
3.3K
Anaphase A and B01:39

Anaphase A and B

4.1K
Microtubules form through the end-to-end polymerization of tubulin heterodimers. Kinetochore microtubules originate from the spindle poles, and their plus-ends connect with the kinetochores on sister-chromatids. Ndc80 protein complexes, present on the kinetochore, form low-affinity links with the plus end of these kinetochore microtubules.
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
4.1K
The Mitotic Spindle02:27

The Mitotic Spindle

6.6K
The mitotic spindle—or spindle apparatus—is a eukaryotic, cytoskeletal structure made up of long protein fibers called microtubules. Formed during cell division, the spindle separates sister chromatids and moves them to opposite ends of a parental cell, where the now individual chromosomes are distributed to two daughter cell nuclei.
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures...
6.6K
Attachment of Sister Chromatids02:57

Attachment of Sister Chromatids

3.3K
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...
3.3K
Separation of Sister Chromatids02:17

Separation of Sister Chromatids

3.6K
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...
3.6K
Cohesins02:20

Cohesins

4.5K
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...
4.5K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The National Joint Registry Data Quality Audit of elbow arthroplasty.

The bone & joint journal·2024
Same author

The fork protection complex generates DNA topological stress-induced DNA damage while ensuring full and faithful genome duplication.

Proceedings of the National Academy of Sciences of the United States of America·2024
Same author

To precept or not to precept: Perspectives from nurse practitioners.

Journal of the American Association of Nurse Practitioners·2024
Same author

Sister chromatid cohesion establishment during DNA replication termination.

Science (New York, N.Y.)·2024
Same author

The Validation of Surgical Simulators: A Technical Report on Current Validation Terminology as a Reference for Future Research.

Cureus·2022
Same author

Cryo-EM structure of the Smc5/6 holo-complex.

Nucleic acids research·2022

Related Experiment Video

Updated: Jun 28, 2025

A Cell Free Assay to Study Chromatin Decondensation at the End of Mitosis
11:04

A Cell Free Assay to Study Chromatin Decondensation at the End of Mitosis

Published on: December 19, 2015

10.3K

Entangling and disentangling mitotic chromosomes.

Jonathan Baxter1

  • 1Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK.

Molecular Cell
|April 19, 2024
PubMed
Summary

Cellular manipulation of long DNA fibers creates topological challenges. New research shows mitotic chromosomes are self-entangled, requiring topoisomerase II (TOP2) activity for disentanglement in late mitosis.

Area of Science:

  • Molecular Biology
  • Genetics
  • Cell Biology

Background:

  • DNA topology and its management are crucial for cellular processes.
  • The challenges of managing extremely long DNA fibers within cells are not fully understood.
  • Chromosome structure and organization during cell division present significant topological hurdles.

Purpose of the Study:

  • To investigate the topological state of DNA within mitotic chromosomes.
  • To identify the mechanisms responsible for resolving DNA entanglements during cell division.
  • To elucidate the role of specific enzymes in managing DNA topology during mitosis.

Main Methods:

  • Microscopy techniques to visualize chromosome structure.
  • Biochemical assays to assess DNA topological states.

More Related Videos

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy
12:04

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy

Published on: June 24, 2019

9.5K
Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes
06:38

Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes

Published on: November 22, 2017

11.9K

Related Experiment Videos

Last Updated: Jun 28, 2025

A Cell Free Assay to Study Chromatin Decondensation at the End of Mitosis
11:04

A Cell Free Assay to Study Chromatin Decondensation at the End of Mitosis

Published on: December 19, 2015

10.3K
Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy
12:04

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy

Published on: June 24, 2019

9.5K
Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes
06:38

Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes

Published on: November 22, 2017

11.9K

  • Genetic manipulation to study the function of topoisomerase II (TOP2).

    • Main Results:

    • Mitotic chromosomes exhibit self-entangled DNA structures.
    • Topoisomerase II (TOP2) activity is essential for disentangling these structures.
    • This disentanglement process is particularly active in late mitosis.

    Conclusions:

    • Mitotic chromosomes are inherently self-entangled.
    • Topoisomerase II (TOP2) plays a critical role in resolving DNA topological challenges during cell division.
    • Understanding these mechanisms is key to comprehending genome stability and accurate chromosome segregation.