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Genome-wide Analysis using ChIP to Identify Isoform-specific Gene Targets
Published on: July 7, 2010
Distintas regiones de Sp1 modulan la unión al ADN y la activación transcripcional
J T Kadonaga1, A J Courey, J Ladika
1Howard Hughes Medical Institute, Department of Biochemistry, University of California, Berkeley 94720.
Science (New York, N.Y.)
|December 16, 1988
Resumen
La proteína Sp1 se une a las secuencias de ADN y activa la transcripción. Los investigadores utilizaron mutantes de deleción para encontrar regiones separadas responsables de la afinidad de unión al ADN, la especificidad de la secuencia a través de dedos de zinc y la activación transcripcional.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
- Genética La genética.
Sus antecedentes:
- Sp1 es un factor de transcripción que se une a las regiones promotoras ricas en GC.
- Desempeña un papel crucial en la activación de la transcripción de la ARN polimerasa II.
- Comprender los dominios funcionales de Sp1 es clave para los estudios de regulación génica.
Objetivo del estudio:
- Para delinear los dominios funcionales de la proteína Sp1.
- Para identificar las regiones responsables de la especificidad y la afinidad de unión al ADN.
- Para mapear segmentos involucrados en la activación transcripcional.
Principales métodos:
- La expresión de los mutantes de deleción Sp1 en Escherichia coli.
- Análisis bioquímicos para evaluar la actividad de unión y transcripción del ADN.
- Ensayos de transcripción in vitro con el uso de mutantes Sp1 purificados.
Principales resultados:
- La unión de ADN específica de la secuencia está mediada por dedos de zinc.
- Una región distinta regula la afinidad de Sp1 con el ADN.
- Dos segmentos separados de Sp1 contribuyen a su función de activación transcripcional.
- Sp1 expresado por E. coli demostrado en estimulación transcripcional in vitro.
Conclusiones:
- Sp1 posee dominios funcionales distintos para la unión al ADN y la activación transcripcional.
- Los dedos de zinc son críticos para el reconocimiento de secuencias específicas de ADN por Sp1.
- La investigación adicional puede aprovechar estos hallazgos para manipular la expresión génica.
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