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Published on: August 6, 2020
Los complejos de histona acetiltransferasa estabilizan la unión swi/snf a los nucleosomas promotores
A H Hassan1, K E Neely, J L Workman
1Howard Hughes Medical Institute and Department, of Biochemistry and Molecular Biology, The Pennsylvania State University, 16802, University Park, PA, USA
Cell
|April 6, 2001
Resumen
El remodelador de cromatina SWI / SNF es reclutado a los promotores por activadores de transcripción, causando la interrupción del nucleosoma. Su retención requiere el activador o la acetilación de histonas por complejos HAT.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La epigenética es la epigenética.
- Biología de la cromatina Biología de la cromatina
Sus antecedentes:
- SWI/SNF es un complejo clave de remodelación de la cromatina.
- Comprender su papel preciso en los promotores de genes es crucial.
- Sus mecanismos de reclutamiento y retención no están completamente aclarados.
Objetivo del estudio:
- Para investigar la función de SWI / SNF en la remodelación de cromatina específica del sitio en los promotores.
- Para analizar la distribución, función y retención de SWI/SNF después del reclutamiento por un activador de transcripción.
- Para aclarar la interacción entre SWI / SNF y los complejos de histona acetiltransferasa (HAT).
Principales métodos:
- Utilizó un sistema purificado para el análisis bioquímico.
- Estudió el reclutamiento de SWI/SNF por un activador de transcripción específico de la secuencia.
- Se evaluó la disrupción del nucleosoma y la retención de SWI/SNF en los nucleosomas promotor-proximales.
- Investigó el papel de la acetilación de histonas por los complejos SAGA y NuA4 HAT.
Principales resultados:
- El reclutamiento de activadores condujo a la unión SWI/SNF y a la ruptura localizada de los nucleosomas.
- La retención de SWI / SNF dependía de la unión continua al activador o la acetilación de la histona.
- La acetilación de la histona por SAGA o NuA4 mejoró la retención SWI/SNF en el promotor.
- Demostró un vínculo funcional entre los HAT y SWI/SNF.
Conclusiones:
- SWI/SNF es reclutado para los promotores y remodela los nucleosomas tras la unión del activador.
- La acetilación de la histona por las HAT estabiliza la unión SWI/SNF en los promotores.
- Estos hallazgos proporcionan una base mecánica para el reclutamiento ordenado de complejos modificadores de la cromatina.
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