Related Experiment Video

Updated: Aug 9, 2026

Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes
06:38

Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes

Published on: November 22, 2017

Key role for cyclin-dependent kinases in the first and second meiotic divisions of rat spermatocytes

Murielle Godet1, Anne Damestoy, Sandrine Mouradian

  • 1INSERM U418/INRA UMR 1245, Hôpital Debrousse, 69322 Lyon 05, France. godet@lyon.inserm.fr

Biology of Reproduction
|December 30, 2003
PubMed

Insights

Inhibiting cyclin-dependent kinase (CDK) activity with roscovitine reduced male germ cell progression through meiosis. This demonstrates CDK

Area of Science:

  • Reproductive biology
  • Cell cycle regulation
  • Molecular endocrinology

Background:

  • The M-phase promoting factor (MPF), a complex of cdc2 (CDK1) and cyclin B1, regulates the G2/M phase transition in cell division.
  • MPF components and histone H1 kinase activity are present in pachytene spermatocytes (PS).
  • Direct inhibition of MPF activity's effect on the G2/M transition in male germ cells remains unproven.

Purpose of the Study:

  • To investigate the role of cyclin-dependent kinase (CDK) activity in male meiosis.
  • To determine if inhibiting CDK activity affects the G2/M transition in pachytene spermatocytes.
  • To establish a functional link between CDK activity and male germ cell meiotic progression.

Main Methods:

  • Coculture of pachytene spermatocytes (PS) with Sertoli cells.
  • Treatment with roscovitine, a potent inhibitor of CDK1, CDK2, and CDK5.
  • Assessment of secondary spermatocyte and round spermatid formation.
  • Measurement of cell viability.
  • Analysis of MPF levels and CDK-associated histone H1 kinase activity.

Main Results:

  • Roscovitine treatment reduced the formation of secondary spermatocytes and round spermatids without affecting cell viability.
  • The inhibitory effect of roscovitine was reversible and concentration-dependent.
  • Roscovitine did not alter MPF levels but inhibited CDK1- and CDK2-associated histone H1 kinase activity in PS.
  • The observed effects were independent of Sertoli cells.

Conclusions:

  • Cyclin-dependent kinase activity is functionally linked to the spontaneous progression of male germ cells through the first and second meiotic divisions.
  • Inhibition of CDK activity disrupts male meiosis at the G2/M transition.
  • This study provides the first evidence for the role of CDK activity in regulating the second meiotic division in male germ cells.

More Related Videos

A Seminiferous Tubule Squash Technique for the Cytological Analysis of Spermatogenesis Using the Mouse Model09:40

A Seminiferous Tubule Squash Technique for the Cytological Analysis of Spermatogenesis Using the Mouse Model

Published on: February 6, 2018

Functional Assessment of Kinesin-7 CENP-E in Spermatocytes Using In Vivo Inhibition, Immunofluorescence and Flow Cytometry09:41

Functional Assessment of Kinesin-7 CENP-E in Spermatocytes Using In Vivo Inhibition, Immunofluorescence and Flow Cytometry

Published on: December 28, 2021

Related Concept Videos

Positive Regulator Molecules01:45

Positive Regulator Molecules

To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
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...
Positive Regulator Molecules02:39

Positive Regulator Molecules

Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
M-Cdk Drives Transition Into Mitosis02:15

M-Cdk Drives Transition Into Mitosis

Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
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...
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,...