Related Experiment Video

Updated: Aug 7, 2026

Techniques for Imaging Prometaphase and Metaphase of Meiosis I in Fixed Drosophila Oocytes
09:11

Techniques for Imaging Prometaphase and Metaphase of Meiosis I in Fixed Drosophila Oocytes

Published on: October 31, 2016

Inhibition of protein kinases by 6-dimethylaminopurine accelerates the transition to interphase in activated mouse

M S Szöllösi1, J Z Kubiak, P Debey

  • 1INRA, Unité de Biologie de la Fécondation, Jouy-en-Josas, France.

Journal of Cell Science
|March 1, 1993
PubMed

Insights

The protein kinase inhibitor 6-dimethylaminopurine (6-DMAP) affects mouse oocyte activation by inhibiting protein phosphorylation. This accelerates some post-fertilization events but also causes abnormalities in microtubule formation and sperm chromatin remodeling.

Area of Science:

  • Cell Biology
  • Developmental Biology
  • Reproductive Biology

Background:

  • Mouse oocyte activation involves a unique post-fertilization period with condensed chromosomes and absent microtubule networks.
  • Maturation-promoting factor (MPF) inactivation occurs, but its role in regulating these events is unclear.
  • Protein phosphorylation is hypothesized to play a critical role in controlling these early post-activation processes.

Purpose of the Study:

  • To investigate the role of protein phosphorylation in mouse oocyte activation using the protein kinase inhibitor 6-dimethylaminopurine (6-DMAP).
  • To determine the effects of inhibiting protein phosphorylation on key post-fertilization events, including microtubule formation and chromatin remodeling.

Main Methods:

  • Treatment of metaphase II-arrested mouse oocytes with 6-DMAP during fertilization or parthenogenetic activation.
  • Assessment of histone H1 kinase activity and protein phosphorylation levels.
  • Microscopic observation of morphological events like sperm chromatin decondensation, microtubule network formation, pronuclear development, spindle rotation, and polar body extrusion.

Main Results:

  • 6-DMAP inhibited protein phosphorylation post-activation without affecting MPF inactivation dynamics.
  • Oocytes treated with 6-DMAP showed accelerated sperm chromatin decondensation, transient recondensation, microtubule network formation, and pronuclear formation.
  • Abnormalities observed included inhibited spindle rotation, impaired protamine-to-histone exchange, and premature nuclear envelope formation around incompletely decondensed sperm chromatin.

Conclusions:

  • 6-DMAP-sensitive kinases are crucial regulators of post-fertilization events in mouse oocytes.
  • These kinases control the formation of the interphase microtubule network, sperm chromatin remodeling, and pronucleus formation.
  • Dysregulation of these phosphorylation events leads to significant developmental abnormalities.

More Related Videos

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I11:13

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Published on: April 10, 2018

Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes10:09

Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes

Published on: September 13, 2022

Related Concept Videos

Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
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.
Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
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 vs. Mitosis02:57

Meiosis vs. Mitosis

Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
Anaphase Promoting Complex00:50

Anaphase Promoting Complex

The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...