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El desenrollo asimétrico de los nucleosomas bajo tensión dirigida por la flexibilidad local del ADN
Thuy T M Ngo1, Qiucen Zhang2, Ruobo Zhou2
1Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801-2902, USA.
Cell
|March 14, 2015
Resumen
El desenrollo del nucleosoma es asimétrico y direccional, controlado por la flexibilidad del ADN. Este descubrimiento revela un nuevo mecanismo para la regulación de genes basado en la secuencia de ADN y modificaciones.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La biofísica es la biofísica.
- Genética La genética.
Sus antecedentes:
- La dinámica de los nucleosomas y la accesibilidad del ADN son cruciales para los procesos nucleares.
- No se comprende bien la influencia de la secuencia de ADN en la dinámica y estabilidad locales del nucleosoma.
Objetivo del estudio:
- Para investigar la dinámica inducida por la fuerza del desenrollo del nucleosoma.
- Determinar el papel de la secuencia y la flexibilidad del ADN en la estabilidad y direccionalidad del nucleosoma.
Principales métodos:
- Se emplearon ensayos de molécula única para observar el desenrollo del nucleosoma bajo fuerza.
- El análisis se centró en la relación entre la flexibilidad del ADN y la dirección de desenrollo.
Principales resultados:
- Los nucleosomas exhiben desenrollo asimétrico y direccional bajo fuerza.
- La flexibilidad del ADN en los cuartos internos dicta la dirección de desenrollo, favoreciendo los lados de ADN más rígidos.
- La orquestación del extremo del nucleosoma amplifica las diferencias de flexibilidad, lo que lleva a una estabilidad asimétrica.
Conclusiones:
- La flexibilidad del ADN es un determinante crítico de la dinámica de los nucleosomas y la estabilidad mecánica.
- Esto proporciona un nuevo mecanismo para la regulación génica modulada por la secuencia de ADN y las modificaciones.
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