Related Experiment Video
Updated: Nov 13, 2025
09:16
Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing
Published on: October 11, 2015
11.9K
Clathrin Heavy Chain 1 Plays Essential Roles During Oocyte Meiotic Spindle Formation and Early Embryonic Development
Zhe Han1, Xin Hao1, Cheng-Jie Zhou1
1State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China.
Frontiers in Cell and Developmental Biology
|March 15, 2021
Summary
Clathrin heavy chain 1 (CLTC) is crucial for sheep oocyte maturation and early embryo development. Impairing CLTC disrupts spindle assembly and chromosome alignment, affecting development.
Area of Science:
- Cell Biology
- Developmental Biology
- Reproductive Biology
Background:
- Clathrin heavy chain 1 (CLTC) is a key protein in coated pits and vesicles, stabilizing mitotic spindle kinetochore fibers.
- While CLTC's role in somatic cell mitosis is known, its function in mammalian oocyte meiosis and early embryo development, particularly in domestic animals, remains under-investigated.
Purpose of the Study:
- To investigate the expression profiles and functional roles of CLTC in sheep oocytes during meiotic maturation and early embryonic development.
Main Methods:
- Quantitative analysis of CLTC expression across oocyte and early embryo stages.
- Immunofluorescence microscopy to determine CLTC localization.
- Oocyte treatments with spindle-disrupting agents (taxol, nocodazole, cold).
- Functional knockdown of CLTC using morpholino injections in oocytes.
- Assessment of spindle assembly, chromosome alignment, and first polar body emission.
- Evaluation of early embryo development after parthenogenetic activation and CLTC knockdown.
Main Results:
- CLTC expression remained high from the germinal vesicle (GV) to metaphase II (MII) stage and was diffusely distributed in the cytoplasm from GV to blastocyst stages.
- CLTC co-localized with beta-tubulin post-GV breakdown (GVBD) during metaphase.
- Spindle-disrupting agents altered CLTC distribution but not expression levels.
- CLTC functional impairment disrupted spindle assembly, chromosomal alignment, and first polar body emission.
- CLTC knockdown before parthenogenetic activation impaired spindle formation and early embryo development.
Conclusions:
- CLTC plays a critical role in sheep oocyte maturation by regulating spindle dynamics.
- CLTC is essential for successful early embryonic development in sheep.
Related Concept Videos
02:02Meiosis II
48.3K
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,...
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,...
48.3K
01:57Meiosis II
189.3K
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...
189.3K
01:08Cloning of Dolly the Sheep
5.9K
The first successfully cloned mammal was Dolly, a sheep, born on 5th July 1996 at Roslin Institute, Scotland. The cloned sheep was named after the American singer Dolly Parton. Dolly lived for seven years and died of respiratory complications, which is speculated to be due to the actual age of her DNA. Because the DNA in cloned cells belongs to an older individual, the cloned individual’s life expectancy may be affected. Indeed, analysis of Dolly’s DNA revealed shorter...
5.9K
01:22Oogenesis
3.0K
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...
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is...
3.0K
02:07Oogenesis
67.5K
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...
67.5K
02:19The Spindle Assembly Checkpoint
3.4K
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...
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...
3.4K