Related Experiment Video

Updated: Jul 17, 2026

Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination
09:24

Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination

Published on: July 18, 2025

Meiotic interference among MLH1 foci requires neither an intact axial element structure nor full synapsis

Esther de Boer1, Axel J J Dietrich, Christer Höög

  • 1Wageningen University, Molecular Genetics group, Arboretumlaan 4, 6703 BD Wageningen, The Netherlands.

Journal of Cell Science
|February 15, 2007
PubMed

Insights

Meiotic crossovers are spaced evenly due to interference. This study found that intact axial elements (AEs) and synaptonemal complexes (SCs) are not required for this crossover interference in mice.

Area of Science:

  • Genetics
  • Cell Biology
  • Molecular Biology

Background:

  • Homologous chromosome crossovers during meiosis exhibit interference, leading to more even spacing than random distribution.
  • Synaptonemal complexes (SCs), formed by axial elements (AEs), are thought to play a role in establishing this interference.
  • The SYCP3 protein is crucial for AE structure and SC formation.

Purpose of the Study:

  • To investigate if intact axial elements (AEs) or complete synaptonemal complexes (SCs) are necessary for crossover interference during mouse meiosis.
  • To determine the role of SYCP3 in the establishment of interference patterns.

Main Methods:

  • Analysis of crossover interference in wild-type and Sycp3(-/-) mutant mice.
  • Estimation of interference levels by measuring the spacing of MLH1 foci (crossover markers) along synaptonemal complexes (SCs).
  • Immunofluorescence microscopy was used to visualize MLH1 foci and SCs.

Main Results:

  • Crossover interference levels, as measured by MLH1 foci spacing, were comparable between wild-type and Sycp3(-/-) mice.
  • Sycp3(-/-) mice exhibit structurally abnormal AEs and incomplete synapsis, indicating a defect in SC formation.

Conclusions:

  • Intact axial element (AE) structure is not required for wild-type levels of crossover interference.
  • Complete synaptonemal complex (SC) formation is not essential for establishing crossover interference during mouse meiosis.
  • These findings suggest that interference mechanisms operate independently of fully formed SCs.

More Related Videos

Super-Resolution Microscopy of the Synaptonemal Complex Within the Caenorhabditis elegans Germline09:14

Super-Resolution Microscopy of the Synaptonemal Complex Within the Caenorhabditis elegans Germline

Published on: September 13, 2022

Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets10:52

Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets

Published on: August 13, 2016

Related Concept Videos

Meiosis II02:02

Meiosis II

Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for meiosis II are similar to mitosis, except that meiosis II occurs in haploid cells, whereas mitosis occurs in diploid cells.
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
Meiosis II01:57

Meiosis II

Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 chromosomes—one from each homologous initial pair. Importantly, each chromosome in these cells is composed of two joined copies, and when these cells enter meiosis II, the goal is to separate such sister chromatids using the same microtubule-based network employed in other division processes. The result of meiosis II is two haploid cells, each containing...
The Spindle Assembly Checkpoint02:19

The Spindle Assembly Checkpoint

The spindle assembly checkpoint is a molecular surveillance mechanism ensuring the fidelity of chromosome segregation during anaphase. The checkpoint monitors the completion of all the prerequisite steps before chromosome segregation to determine whether the segregation process should proceed or be delayed.
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Attachment of Sister Chromatids02:57

Attachment 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...
Separation of Sister Chromatids02:17

Separation 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...
Forces Acting on Chromosomes02:11

Forces Acting on Chromosomes

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...