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Zeste codifica un factor de transcripción específico de la secuencia que activa el promotor Ultrabithorax in vitro
M D Biggin1, S Bickel, M Benson
1Howard Hughes Medical Institute, Department of Biochemistry, University of California Berkeley 94720.
Cell
|June 3, 1988
Resumen
La proteína zeste en Drosophila se une a sitios específicos del ADN y activa la transcripción del gen Ubx. Este hallazgo sugiere un mecanismo para la transvección, un proceso que involucra cromosomas emparejados.
Área de la Ciencia:
- * Biología del desarrollo.
- * La genética molecular es genética molecular.
- * Regulación de los genes.
Sus antecedentes:
- * Zeste es un gen regulador en Drosophila melanogaster esencial para la transvección en el complejo bithorax.
- * La transvección es un fenómeno en el que los alelos en cromosomas homólogos influyen en la expresión del otro.
Objetivo del estudio:
- * Investigar el mecanismo molecular por el cual la proteína zeste regula la transcripción.
- * Para determinar si la proteína zeste se une directamente y activa el promotor del gen Ultrabithorax (Ubx).
Principales métodos:
- * Purificación de la proteína zeste de las células de Drosophila y E. coli.
- * Ensayos de transcripción in vitro utilizando promotores de Ubx y Adh (alcohol deshidrogenasa).
- * Análisis de los sitios de unión a la proteína zeste aguas arriba del sitio de inicio de la transcripción de Ubx.
Principales resultados:
- * La proteína zeste purificada se une a múltiples sitios ubicados en el 5' del sitio de iniciación del ARN Ubx.
- * La proteína Zeste activa la transcripción de Ubx in vitro.
- * La activación es dependiente de la presencia de sitios de unión del zeste; no se observó activación con promotores mutados de Ubx o Adh.
Conclusiones:
- * La transvección implica elementos reguladores que actúan en el nivel de iniciación de la transcripción.
- * La activación transcripcional mediada por zeste puede ser mecánicamente similar a la función potenciadora, pero ocurre a través de cromosomas emparejados.
- * Zeste podría tener un papel más significativo en la regulación de Ubx y otros genes diana de lo que se entendía anteriormente.
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