Video Experimental Relacionado
Updated: Jun 26, 2025
12:09
Protocol for Human Blastoids Modeling Blastocyst Development and Implantation
Published on: August 10, 2022
6.4K
Los dos primeros blastómeros contribuyen de manera desigual al embrión humano
Sergi Junyent1, Maciej Meglicki2, Roman Vetter3
1Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
Cell
|May 14, 2024
Resumen
El desarrollo temprano del embrión humano muestra una asimetría clonal significativa. La mayoría de las células del cuerpo se originan a partir de un solo blastómero de 2 células, influenciado por el tiempo de división y la internalización celular.
Área de la Ciencia:
- Biología del desarrollo
- La embriogénesis humana
- Rastreo del linaje celular
Sus antecedentes:
- Los estudios retrospectivos sugieren que los desequilibrios clonales en los cuerpos humanos adultos se originan en la etapa embrionaria de 2 células.
- Los mecanismos que establecen estas asimetrías clonales embrionarias tempranas siguen siendo en gran medida desconocidos.
Objetivo del estudio:
- Para rastrear los linajes celulares en embriones humanos.
- Identificar la contribución de cada blastómero en el estadio de 2 células a los principales linajes embrionarios.
- Para aclarar los orígenes de la asimetría clonal en el desarrollo humano.
Principales métodos:
- Imágenes en vivo de embriones humanos.
- Técnicas de etiquetado celular no invasivas.
- Modelado computacional y predicciones.
- Seguimiento del linaje desde la etapa de 2 células.
Principales resultados:
- La mayoría de las células del epiblasto (cuerpo) se derivan de solo uno de los dos blastómeros del estadio de 2 células.
- Un cuello de botella de 1-3 células que se internalizan ocurre durante la transición de la etapa de 8 a 16 células.
- Las células internalizadas se derivan preferentemente del blastómero que se dividió primero en la etapa de 2 células.
Conclusiones:
- La dinámica de división celular en la etapa de 2 células tiene un impacto significativo en la asignación del linaje embrionario.
- Un cuello de botella de internalización celular crítico da forma a la composición clonal temprana.
- Estos eventos tempranos establecen la base para la asimetría clonal en el cuerpo humano en desarrollo.
Videos de Conceptos Relacionados
01:33Cleavage and Blastulation
45.1K
After a large-single-celled zygote is produced via fertilization, the process of cleavage occurs while zygotes travel through the uterine tube. Cleavage is a mitotic cell division that does not result in growth. With each round of successive cell division, daughter cells get increasingly smaller.
45.1K
01:56Gastrulation
57.3K
Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata...
57.3K
01:10Zygotic Development And Stem Cell Formation
5.2K
The development of all multicellular organisms starts with the fusion of haploid cells called sperm and egg to form a diploid zygote. A zygote is a totipotent cell that can develop into a complete organism. The zygote undergoes cell division or cleavage to form an 8-cell mass. Until this stage, the cells are spherical, loosely attached, and remain totipotent. Totipotent cells are capable of developing both the embryonic and the extraembryonic tissues. However, as they continue to divide, they...
5.2K
01:38Fertilization
70.9K
During fertilization, an egg and sperm cell fuse to create a new diploid structure. In humans, the process occurs once the egg has been released from the ovary, and travels into the fallopian tubes. The process requires several key steps: 1) sperm present in the genital tract must locate the egg; 2) once there, sperm need to release enzymes to help them burrow through the protective zona pellucida of the egg; and 3) the membranes of a single sperm cell and egg must fuse, with the sperm...
70.9K
01:29Nondisjunction
75.5K
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
75.5K
01:07Teratogenicity
2.4K
The ability of a drug to produce structural deformations and functional abnormalities in the developing embryo or the fetus is called teratogenicity, and the drug producing this effect is known as a teratogen. Teratogenic effects include stillbirth, miscarriage, intrauterine growth restriction, and neurocognitive delay. A teratogen may affect the embryo at different stages of development, which is important in determining the type and extent of the damage. During blastocyst formation, the early...
2.4K