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Biochemical Assays for Analyzing Activities of ATP-dependent Chromatin Remodeling Enzymes
Published on: October 25, 2014
La movilización de los nucleosomas catalizada por el complejo SWI/SNF de la levadura
I Whitehouse1, A Flaus, B R Cairns
1Division of Gene Regulation, University of Dundee, UK.
Nature
|August 31, 1999
Resumen
El complejo SWI / SNF de la levadura reposiciona los nucleosomas a lo largo del ADN a través de un deslizamiento dependiente de ATP. Este mecanismo de remodelación de la cromatina puede ser un proceso general para la regulación génica.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Regulación genética Reglamento genético.
- Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina Dinámica de la cromatina
Sus antecedentes:
- La regulación génica se basa en la creación de estructuras locales de cromatina permisivas para la transcripción.
- El complejo SWI / SNF de la levadura es un remodelador clave dependiente de ATP de la estructura de la cromatina.
- El mecanismo preciso de la interrupción de la cromatina mediada por SWI / SNF sigue sin estar claro.
Objetivo del estudio:
- Para dilucidar la vía por la cual el complejo SWI / SNF de la levadura remodela la cromatina.
- Para investigar el mecanismo de reposicionamiento de los nucleosomas por SWI/SNF.
Principales métodos:
- Utilizó un sistema modelo para estudiar la actividad del complejo SWI/SNF de la levadura.
- Empleó barreras de ADN para sondear los mecanismos de desplazamiento de los nucleosomas.
- Se analizó el reposicionamiento del nucleosoma dependiente del ATP.
Principales resultados:
- Demostró que el complejo SWI/SNF de la levadura reposiciona los nucleosomas de una manera dependiente del ATP.
- Se demostró que el reposicionamiento del nucleosoma favorece la fijación a sitios aceptores en la misma molécula de ADN (en cis).
- Se encontró que las barreras del ADN impiden el desplazamiento del octámero de histona mediado por SWI / SNF, lo que indica deslizamiento o seguimiento.
Conclusiones:
- Se concluyó que SWI/SNF cataliza la redistribución del nucleosoma a lo largo del ADN en cis.
- Se propuso que el deslizamiento del nucleosoma mediado por SWI / SNF es un mecanismo general para la remodelación de la cromatina dependiente de ATP.
- Destacó la importancia de SWI/SNF en el establecimiento de la topología de la cromatina transcripción-permisivos.
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