Video Experimental Relacionado
Updated: Jun 8, 2026
07:16
Isolation and Characterization of Mouse Antral Oocytes Based on Nucleolar Chromatin Organization
Published on: January 7, 2016
El ligando de células de granulosa NPPC y su receptor NPR2 mantienen la detención meiótica en los ovocitos de ratón
Meijia Zhang1, You-Qiang Su, Koji Sugiura
1State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, People's Republic of China.
Science (New York, N.Y.)
|October 16, 2010
Resumen
El ligando del péptido natriurético precursor tipo C (NPPC) de las células de granulosa y su receptor NPR2 en las células de cúmulo previenen la detención meiotica de los ovocitos. Este mecanismo es crucial para la fertilidad femenina y la ovulación oportuna.
Área de la Ciencia:
- Biología Reproductiva Biología Reproductiva.
- La señalización celular de las células.
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- Los ovocitos de mamíferos se detienen en la meiosis dentro de los folículos grafianos.
- Las células de la granulosa juegan un papel crítico en el mantenimiento de esta detención meiotic, evitando la maduración prematura.
- Los mecanismos moleculares que subyacen a esta detención no se comprenden completamente.
Objetivo del estudio:
- Investigar el papel del precursor del péptido natriurético tipo C (NPPC) y su receptor NPR2 en el mantenimiento de la detención meiotica de los ovocitos.
- Para dilucidar la vía de señalización que involucra a NPPC y NPR2 en células de granulosa y cúmulo.
- Determinar el impacto de esta vía en la fertilidad femenina y la sincronía de la ovulación.
Principales métodos:
- Análisis de la expresión de ARNm NPPC y NPR2 en granulosa mural de ratón y células de cúmulo.
- Experimentos in vitro que miden los niveles de GMPc y la reanudación meiótica en respuesta al NPPC.
- Generación y análisis de ratones mutantes Nppc y Npr2 para evaluar la función in vivo.
Principales resultados:
- Las células de granulosa mural expresan el ARNm NPPC, mientras que las células de cúmulo expresan el ARNm NPR2.
- El tratamiento con NPPC aumentó los niveles de GMPc en las células acumuladas y en los ovocitos, inhibiendo la reanudación meiótica in vitro.
- Los ratones mutantes Nppc y Npr2 exhibieron deterioro de la detención meiótica, lo que condujo a la reanudación precoz de la meiosis.
- Se descubrió que los factores derivados de los ovocitos promueven la expresión de Npr2 en las células del cúmulo.
Conclusiones:
- La vía de señalización NPPC-NPR2 es esencial para mantener la detención meiotica de los ovocitos en los folículos de mamíferos Graafianos.
- Esta vía previene la maduración meiótica precoz, asegurando el momento adecuado de la ovulación y la fertilidad femenina.
- La desregulación de este sistema puede conducir a infertilidad y anormalidades del desarrollo.
Videos de Conceptos Relacionados
02:02Meiosis 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,...
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,...
01:23Negative 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.
01:45Regulation of Nuclear Protein Sorting
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
01:22Oogenesis
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...
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...
01:31Transducer Mechanism: Nuclear Receptors
Nuclear receptors, or NRs, are unique transcription factors that regulate gene transcription and affect the cellular pathways involved in reproduction, development, or metabolism. Their ability to be stimulated by small lipophilic ligands and control vital cellular processes makes them ideal drug targets. Nearly 10-15% of currently prescribed drugs target these receptors.
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
02:23Abnormal Proliferation
Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...