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High-throughput Purification of Affinity-tagged Recombinant Proteins
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Una holoenzima de ARN polimerasa II de mamíferos que contiene todos los componentes requeridos para la iniciación de
V Ossipow1, J P Tassan, E A Nigg
1Département de Biologie Moléculaire, Sciences II, Université de Genéve, Switzerland.
Cell
|October 6, 1995
Resumen
Los investigadores identificaron una holoenzima completa de ARN polimerasa II en células de mamíferos, lo que sugiere similitudes entre la iniciación de la transcripción en eucariotas y procariotas. Este complejo incluye factores clave de transcripción esenciales para la expresión génica.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
- Genética La genética.
Sus antecedentes:
- La proteína quinasa MO15/CDK7 está vinculada al factor de transcripción TFIIH.
- MO15/CDK7 fosforila el dominio carboxiterminal de la ARN polimerasa II. también conocido como ARN polimerasa II.
Objetivo del estudio:
- Para investigar la asociación de MO15/CDK7 con el mecanismo de transcripción de la ARN polimerasa II.
- Para identificar los componentes de la holoenzima ARN polimerasa II en las células de mamíferos.
Principales métodos:
- Coinmunoprecipitación de anticuerpos monoclonales utilizando el anticuerpo anti-MO15/CDK7.
- Análisis de extractos nucleares de hígado de rata.
Principales resultados:
- El anticuerpo MO15/CDK7 coinmunoprecipitado por la ARN polimerasa II, TFIID, TFIIB, TFIIH, TFIIF y TFIIE.
- El inmunoprecipitado carecía de proteínas activadoras de la transcripción como HNF1, HNF4 y C/EBP alfa.
- Se encontraron pruebas de una holoenzima de la ARN polimerasa II que inicia de forma autónoma en las células de mamíferos.
Conclusiones:
- Las células de los mamíferos contienen una holoenzima ARN polimerasa II capaz de iniciar la actividad autónoma.
- Este hallazgo sugiere paralelismos funcionales entre la iniciación de la transcripción en eucariotas y procariotas.
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