Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Oogenesis

Oogenesis

In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal...

Oogenesis

Oogenesis

Oogenesis, the process of developing egg cells (female gametes), occurs within the ovaries and is fundamental to female fertility. This sequence begins during fetal development when diploid oogonia in the developing ovaries undergo mitotic divisions to produce primary oocytes. By birth, these primary oocytes enter prophase I of meiosis but become arrested in this stage, remaining suspended until puberty.
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...

Meiosis vs. Mitosis

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...

Meiosis II

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...

Meiosis II

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,...

Crossing Over

Crossing Over

Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...

You might also read

Related Articles

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

Sort by

Same author

Inter-individual gene expression variability implies stable regulation of brain-biased genes across organs in three ray-finned fishes.

bioRxiv : the preprint server for biology·2026

Same author

Circulating microRNAs reveal egg-brain crosstalk and a brain-predominant microRNA linked to the onset of the next reproductive cycle in iteroparous salmonids.

BMC biology·2026

Same author

Corrigendum to "The role of multiple vitellogenins in early development of fishes" [Gen. Comp. Endocrinol. 351 (2024) 114479].

General and comparative endocrinology·2026

Same author

APOBEC cellular enzymes as 'court jesters' in SARS-CoV-2 evolution.

Virus genes·2026

Same author

The Phylogenomic Approach Suggests That Butyrophilins Have Ligands Beyond Gamma-Delta Receptors.

International journal of molecular sciences·2026

Same author

Insights and emerging perspectives from the 2025 Medaka PI/ERC IndiGene meeting: Heidelberg July 22-24, 2025.

Developmental dynamics : an official publication of the American Association of Anatomists·2026

Search research articles

Related Experiment Video

Updated: May 17, 2026

Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes

Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes

Published on: September 13, 2022

Oocyte-somatic cells interactions, lessons from evolution.

Cathy Charlier¹, Jérôme Montfort, Olivier Chabrol

¹INRA, UR LPGP Fish Physiology and Genomics, Campus de Beaulieu, Rennes, France.

|October 23, 2012

Summary

This summary is machine-generated.

Somatic cells provide crucial signals for egg cell development. This study identified conserved molecular players across vertebrates, revealing shared mechanisms for oocyte developmental competence acquisition, even with invertebrates.

More Related Videos

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Published on: April 10, 2018

Related Experiment Videos

Last Updated: May 17, 2026

Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes

Evaluation of the Spindle Assembly Checkpoint Integrity in Mouse Oocytes

Published on: September 13, 2022

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I

Published on: April 10, 2018

Area of Science:

Reproductive Biology
Developmental Biology
Comparative Genomics

Background:

Somatic cells are vital for oocyte developmental competence, but mechanisms remain unclear, especially in non-mammalian species.
Understanding these mechanisms is crucial for improving egg quality and reproductive success.

Purpose of the Study:

To identify key molecular signals from somatic cells involved in oocyte developmental competence acquisition.
To investigate evolutionary-conserved mechanisms shared across vertebrate species.

Main Methods:

Parallel transcriptomic analysis was performed on 4 vertebrate species (teleost fish, amphibian, two mammals) at critical developmental stages.
Comparative analysis identified species-specific and orthologous genes with similar expression profiles.

Main Results:

A high number of orthologous genes with conserved expression profiles were found in tetrapods and across all 4 vertebrates.
Conserved genes are involved in cellular energy metabolism, cell-to-cell communication, and meiosis control.
Novel somatic molecular actors were identified, some of which are active in Drosophila oogenesis.

Conclusions:

The study reveals evolutionary-conserved, somatic-derived mechanisms crucial for oocyte developmental competence acquisition in vertebrates.
These findings suggest shared molecular players between vertebrates and even metazoans, highlighting the somatic compartment's contribution to oocyte quality.
The conserved mechanisms underscore the importance of somatic-oocyte interactions in reproductive evolution.