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La activación de la transcripción génica de clase II por factores reguladores es potenciada por una nueva actividad
M Meisterernst1, A L Roy, H M Lieu
1Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021.
Cell
|September 6, 1991
Resumen
Se identificó un nuevo factor de transcripción dependiente del activador, USA. Comprende dos componentes que modulan la transcripción al interactuar con el TFIID, mejorando la función del activador.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
- Reglamento genético Reglamento genético.
Sus antecedentes:
- Los activadores de la transcripción regulan la expresión génica mediante la interacción con la maquinaria de transcripción basal.
- El complejo TFIID juega un papel crucial en el inicio de la transcripción.
Objetivo del estudio:
- Para caracterizar una nueva actividad (EE.UU.) que estimula la transcripción dependiente del activador.
- Para aclarar el mecanismo por el cual EE.UU. influye en la iniciación de la transcripción.
Principales métodos:
- Sistema de transcripción reconstituido utilizando componentes purificados.
- Ensayos de desplazamiento de la movilidad del gel para estudiar las interacciones proteína-ADN y proteína-proteína.
- Purificación de la nueva actividad (EE.UU.).
Principales resultados:
- Estados Unidos estimuló la transcripción dependiente del activador de 10 a 50 veces en un sistema reconstituido con TFIID natural.
- Función de activador potenciado cuando se resuelve en dos componentes con efectos opuestos en la actividad del promotor central.
- Los experimentos de desplazamiento de movilidad de gel revelaron interacciones físicas entre un componente inhibidor de USA y TFIID.
Conclusiones:
- USA contiene cofactores que se asocian con el complejo de preiniciación.
- Estos cofactores reducen la actividad del promotor basal y mejoran la transcripción dependiente del activador.
- EE.UU. representa un nuevo mecanismo regulador en la iniciación de la transcripción.
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