Video Experimental Relacionado
Updated: Jul 17, 2026
07:55
Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
El complejo de reconocimiento de origen funciona en la cohesión de las cromatidas hermanas en Saccharomyces
Kenji Shimada1, Susan M Gasser
1Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland.
Cell
|January 16, 2007
Resumen
La proteína Orc2 del complejo de reconocimiento de origen (ORC) es crucial para mantener la cohesión de las cromatidas hermanas durante la división celular. El agotamiento de Orc2 perjudica la cohesión, destacando un nuevo papel para ORC en la segregación cromosómica más allá de la replicación del ADN.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- Genética La genética.
Sus antecedentes:
- La segregación cromosómica de alta fidelidad depende de la cohesión oportuna de las cromatidas hermanas, mediada principalmente por el complejo de Cohesin.
- La resolución de la cohesina en la transición de metafase a anafase es crítica para una división celular precisa.
Objetivo del estudio:
- Investigar el papel de la proteína Orc2 del complejo de reconocimiento de origen (ORC) en la progresión del ciclo celular y la cohesión de las cromatidas hermanas.
- Para determinar si Orc2 influye en la cohesión independientemente de la asociación del complejo de cohesión con la cromatina.
Principales métodos:
- Agotamiento de Orc2 en una cepa de levadura después del ensamblaje del complejo de pre-replicación.
- Análisis de la progresión del ciclo celular, el daño del ADN y los puntos de control del huso.
- Evaluación de la cohesión de las cromatidas hermanas y la localización de la subunidad de cohesión.
- Re-expresión de Orc2 y estudios de localización dirigidos.
Principales resultados:
- El agotamiento de Orc2 retrasó la mitosis debido al daño del ADN y la activación del punto de control del huso.
- La cohesión de las cromatidas hermanas se vio afectada en las células empobrecidas de Orc2, a pesar de la asociación de cohesión normal.
- La reexpresión de Orc2 restauró la cohesión cromatídica.
- La orientación de Orc2 a un locus específico suprimió la separación prematura de las cromatidas hermanas en un mutante de cohesión.
Conclusiones:
- El complejo de reconocimiento de origen (CRO) juega un papel importante en el establecimiento y mantenimiento de la cohesión entre las cromatidas hermanas.
- La cohesión mediada por ORC actúa en una vía aditiva al emparejamiento mediado por Cohesin.
- Orc2 es esencial para la correcta segregación cromosómica a través de su papel en la cohesión de las cromatidas hermanas.
Más Videos Relacionados
Videos de Conceptos Relacionados
02:20Cohesins
Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
02:20Cohesins
Cohesin protein complexes are a molecular glue that holds two sister chromatids together. They play an important role both in mitosis and meiosis. In mitosis, all cohesin complexes present on the chromosomes are removed before the start of the anaphase stage.
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
Cohesin complexes in Meiotic Division
Meiosis involves two distinct rounds of chromosomal segregation and cell divisions— Meiosis I followed by Meiosis II – producing four daughter cells. Meiosis I includes the separation of homologous...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...