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El control temporal epigenético de los genes Hox del ratón en vivo
Natalia Soshnikova1, Denis Duboule
1National Research Centre Frontiers in Genetics, Department of Zoology and Animal Biology, University of Geneva, Sciences III, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland.
Science (New York, N.Y.)
|June 6, 2009
Resumen
El reloj de Hox controla el desarrollo de los vertebrados mediante la activación de genes en orden genómico. Este estudio revela que los cambios en las modificaciones de la cromatina y la organización de genes agrupados son cruciales para esta regulación temporal de los genes.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- La epigenética es la epigenética.
- La genómica es la genómica.
Sus antecedentes:
- El desarrollo de los vertebrados depende del control temporal preciso de la activación del gen Hox.
- El "reloj de Hox" coordina el patrón corporal, pero su mecanismo es poco conocido.
Objetivo del estudio:
- Aclarar el mecanismo detrás de la activación temporal de los genes Hox durante el desarrollo de los vertebrados.
- Investigar el papel del estado de la cromatina y la organización de los grupos de genes en la regulación de los genes Hox.
Principales métodos:
- Análisis de las modificaciones dinámicas de la cromatina (marcas de activación y represivas) durante la embriogénesis del ratón.
- Utilizando un modelo de ratón genéticamente modificado con un grupo Hox dividido.
Principales resultados:
- La activación sucesiva del gen Hox se correlaciona con las transiciones direccionales del estado de la cromatina.
- El mantenimiento de la integridad del grupo de genes Hox es esencial para la correcta activación temporal.
- El aumento de las modificaciones competentes para la transcripción se corresponde con la disminución de las marcas represivas.
Conclusiones:
- Las modificaciones de la cromatina juegan un papel importante en la regulación temporal de los genes Hox.
- La organización agrupada de los genes Hox es necesaria para implementar su secuencia de activación temporal.
- Esta investigación proporciona información sobre los mecanismos epigenéticos que gobiernan la expresión génica del desarrollo.
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