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Interacción cooperativa de un factor de iniciación de transcripción de unión al iniciador y el activador de
A L Roy1, M Meisterernst, P Pognonec
1Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021.
Nature
|November 21, 1991
Resumen
Los investigadores descubrieron un nuevo factor de transcripción, TFII-I, que se une a los elementos iniciadores (Inr). Este factor juega un papel en la transcripción basal e interactúa con la USF, lo que sugiere nuevas vías de comunicación en 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 por la ARN polimerasa II implica factores comunes y elementos promotores mínimos como la caja TATA y el iniciador (Inr).
- La unión de TFIID al elemento TATA facilita el ensamblaje del complejo de preiniciación.
- Los factores que funcionan en el elemento Inr han permanecido indefinidos.
Objetivo del estudio:
- Identificar y caracterizar nuevos factores involucrados en la iniciación de la transcripción en el elemento Inr.
- Investigar el papel de estos factores en la transcripción basal y su relación con otros factores de transcripción conocidos.
Principales métodos:
- Identificación de un nuevo factor de transcripción, TFII-I, que se une específicamente a los elementos Inr.
- Pruebas para demostrar el apoyo de TFII-I a la transcripción basal del promotor tardío mayor del adenovirus.
- Estudios inmunológicos y de unión para explorar la relación entre TFII-I, USF y sus respectivos sitios de unión (cajas Inr y E).
Principales resultados:
- Se identificó un nuevo factor, TFII-I, y se demostró que se une específicamente a los elementos Inr.
- TFII-I apoya la transcripción basal y está inmunológicamente relacionado con el activador de hélice-bucle-hélice USF.
- TFII-I y USF exhiben enlaces cooperativos en los sitios de Inr y E, lo que indica una interacción cruzada.
Conclusiones:
- El TFII-I representa una nueva clase de factores de iniciación de la transcripción.
- Las interacciones de TFII-I en múltiples elementos promotores sugieren nuevos mecanismos de comunicación entre los factores reguladores y la maquinaria general de transcripción.
- La vinculación cooperativa de TFII-I y USF destaca las complejas interacciones regulatorias en las regiones promotoras.
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