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La coordinación de la replicación del ADN y la modificación de las histonas por el complejo Rik1-Dos2
Fei Li1, Rob Martienssen, W Zacheus Cande
1Department of Biology, New York University, New York, New York 10003, USA. fl43@nyu.edu
Nature
|July 5, 2011
Resumen
La levadura de fisión utiliza la interferencia del ARN para mantener la heterocromatina durante la replicación del ADN. Un complejo recién identificado vincula la replicación del ADN con la metilación de las histonas, asegurando la herencia epigenética.
Área de la Ciencia:
- La epigenética es la epigenética.
- Biología Molecular Biología Molecular
- Biología de la cromatina Biología de la cromatina
Sus antecedentes:
- Las marcas de modificación de histonas son cruciales para los procesos de cromatina.
- La herencia exacta de las marcas de histona durante la replicación del ADN sigue siendo poco conocida.
- La levadura de fisión utiliza la interferencia del ARN (RNAi) para la metilación de histonas regulada por el ciclo celular.
Objetivo del estudio:
- Para caracterizar un nuevo complejo de silenciamiento en la levadura de fisión.
- Para investigar el papel del complejo en la regulación de la heterocromatina y la replicación del ADN.
- Para dilucidar el vínculo molecular entre la replicación del ADN y la transmisión de marcas epigenéticas.
Principales métodos:
- Caracterización de un complejo silenciador que contiene Dos2, Rik1, Mms19 y Cdc20.
- Análisis de la actividad de la ARN polimerasa II dentro de la heterocromatina.
- Evaluación del requisito del complejo para la replicación del ADN y el ensamblaje de la heterocromatina.
Principales resultados:
- Se identificó un nuevo complejo de silenciamiento que involucra a Dos2, Rik1, Mms19 y Cdc20.
- Este complejo regula la actividad de la ARN polimerasa II en la heterocromatina.
- El complejo es esencial para la replicación del ADN y el ensamblaje de la heterocromatina en la levadura de fisión.
Conclusiones:
- El complejo identificado proporciona un vínculo molecular entre la replicación del ADN y la metilación de histonas.
- Este hallazgo arroja luz sobre los mecanismos de transmisión de la marca epigenética durante el ciclo celular.
- Comprender este proceso es clave para comprender cómo los estados epigenéticos se heredan a través de las generaciones.
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