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Función del complejo que contiene TAF (II) sin TBP en la transcripción por la ARN polimerasa II
1Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Illkirch, CU de Strasbourg, France.
Nature
|May 29, 1998
Resumen
Los investigadores descubrieron un nuevo complejo proteico que inicia la transcripción génica sin TFIID. Este complejo libre de TBP sugiere vías alternativas para la transcripción de la ARN polimerasa II en las células, lo que afecta la regulación génica.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Regulación genética Reglamento genético.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La iniciación de la transcripción génica por la ARN polimerasa II implica el ensamblaje del complejo de preiniciación.
- Tradicionalmente se cree que esta asamblea está exclusivamente nucleada por TFIID vinculante a los promotores.
Objetivo del estudio:
- Para investigar mecanismos alternativos de iniciación de la transcripción.
- Caracterizar los nuevos complejos proteicos involucrados en la transcripción de la ARN polimerasa II.
Principales métodos:
- Aislamiento y caracterización de un nuevo complejo multiproteico.
- Pruebas de transcripción in vitro con promotores que contienen y carecen de TATA.
- Pruebas que utilizan anticuerpos anti-TBP para evaluar la actividad independiente de TBP.
Principales resultados:
- Se identificó un complejo multiproteínico libre de TBP compuesto de TAF (II) s y otras proteínas.
- Este complejo reemplazó con éxito a TFIID para iniciar la transcripción en varios promotores.
- La actividad del complejo no se vio afectada por los anticuerpos anti-TBP, lo que confirma la función independiente de TBP.
Conclusiones:
- La transcripción de ARN polimerasa II libre de TBP es posible en las células de mamíferos.
- Varios complejos de preiniciación pueden regular la expresión génica a través de vías alternativas.
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