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Combined DNA-RNA Fluorescent In situ Hybridization (FISH) to Study X Chromosome Inactivation in Differentiated Female Mouse Embryonic Stem Cells
Published on: June 14, 2014
RNF12 es un activador X-Encoded dependiente de la dosis de la inactivación del cromosoma X
Iris Jonkers1, Tahsin Stefan Barakat, Eskeatnaf Mulugeta Achame
1Department of Reproduction and Development, Erasmus MC, University Medical Center, 3000 CA Rotterdam, The Netherlands.
Cell
|December 1, 2009
Resumen
Los investigadores identificaron a RNF12, una ligasa de ubiquitina E3, como un activador clave de la inactivación del cromosoma X (XCI). Su dosificación influye en la iniciación de XCI en mamíferos placentarios, lo que afecta a la compensación de la dosis del gen.
Área de la Ciencia:
- Genética La genética.
- La epigenética es la epigenética.
- Desarrollo de los mamíferos Desarrollo de los mamíferos
Sus antecedentes:
- La inactivación del cromosoma X (XCI) iguala la dosis de genes entre los sexos en los mamíferos placentarios.
- La iniciación de XCI es un proceso estocástico regulado por factores codificados por X.
Objetivo del estudio:
- Para identificar nuevos activadores de la inactivación del cromosoma X.
- Para aclarar el papel de RNF12 en la iniciación de XCI.
Principales métodos:
- Sobreexpresión de RNF12 de ratón y humano en células madre embrionarias (CEM) de ratón macho y hembra.
- Análisis de la iniciación de XCI en las células transgénicas RNF12 y las ESC heterocigotas Rnf12.
- Evaluación de la integridad del marco de lectura abierto de RNF12 y los niveles de expresión.
Principales resultados:
- El aumento de las copias de RNF12 desencadenó XCI en los ESC masculinos y XCI bialélico en las ESC femeninas.
- La actividad de iniciación de XCI de RNF12 dependía de su marco de lectura abierto y su nivel de expresión.
- La iniciación de XCI se redujo en la diferenciación de las hembras heterocigotas Rnf12(+/-) ESC.
Conclusiones:
- RNF12 se ha identificado como un activador crucial del XCI.
- RNF12 juega un papel dependiente de la dosis en el conteo y la iniciación de XCI.
- Este descubrimiento proporciona nuevos conocimientos sobre los mecanismos moleculares de la compensación de dosis del cromosoma X.
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