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Biochemical Assays for Analyzing Activities of ATP-dependent Chromatin Remodeling Enzymes
Published on: October 25, 2014
El deslizamiento del octámero de histona dependiente de ATP mediado por el complejo de remodelación de la cromatina
A Hamiche1, R Sandaltzopoulos, D A Gdula
1Laboratory of Molecular Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA.
Cell
|July 10, 1999
Resumen
El complejo NURF de Drosophila (Factor de Remodelación Nucleosómica) reposiciona los nucleosomas en el ADN. Este remodelador de cromatina facilita el deslizamiento del octámero de histona manteniendo su integridad estructural.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Biología de la cromatina Biología de la cromatina
- La bioquímica es la bioquímica.
Sus antecedentes:
- Los complejos de remodelación de la cromatina dependientes de ATP juegan un papel crucial en los procesos de plantilla de ADN.
- El factor de remodelación de nucleosomas (NURF) que contiene ISWI de Drosophila es un jugador clave en la dinámica de la cromatina.
Objetivo del estudio:
- Para investigar el mecanismo por el cual Drosophila NURF remodela los nucleosomas.
- Para caracterizar el movimiento y la integridad de los nucleosomas durante la remodelación mediada por NURF.
Principales métodos:
- Reconstitución de los mononucleosomas en el ADN promotor del hsp70.
- Análisis de la redistribución de los nucleosomas utilizando digestión NURF y Exo III.
- Evaluación de la retención de histona del núcleo durante la remodelación.
Principales resultados:
- NURF cataliza la redistribución bidireccional de los mononucleosomas en el ADN.
- Los nucleosomas adoptan rápidamente una posición predominante, con movimientos que ocurren en cis.
- La integridad del octámero de histona se mantiene durante todo el proceso de remodelación, lo que sugiere un deslizamiento de corto alcance.
Conclusiones:
- Drosophila NURF remodela los nucleosomas facilitando el deslizamiento de corto alcance del octámero de histona.
- El complejo parece reducir la energía de activación para el reposicionamiento del nucleosoma.
- La remodelación mediada por NURF preserva la estructura general del nucleosoma.
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