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Clonado molecular de ADNc que codifica la proteína p190 asociada a GAP: implicaciones para una vía de señalización
J Settleman1, V Narasimhan, L C Foster
1Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge 02142.
Cell
|May 1, 1992
Resumen
Los investigadores identificaron una proteína, p190, que tiene complejos con la proteína activadora de la ras GTPasa (GAP) en las células estimuladas. Esta proteína tiene dominios que sugieren roles en la regulación de la GTPasa y la represión transcripcional, potencialmente vinculando la señalización ras a la expresión génica nuclear.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La señalización celular de las células.
- Genética La genética.
Sus antecedentes:
- Ras GTPase-activating protein (GAP) juega un papel crucial en la regulación de las vías de señalización ras.
- Se ha observado que la proteína p190 forma complejos con ras GAP en células estimuladas y transformadas.
Objetivo del estudio:
- Para clonar y caracterizar la proteína p190.
- Para dilucidar los dominios funcionales y los roles potenciales de p190 en la señalización celular.
Principales métodos:
- La clonación de los ADN complementarios (ADNc) que codifican la proteína p190.
- Análisis bioinformático de la secuencia de proteínas predicha para identificar dominios homólogos.
Principales resultados:
- La secuencia de la proteína p190 contiene tres dominios distintos con una homología significativa a las proteínas conocidas.
- Un dominio N-terminal muestra homología a los motivos de la GTPasa.
- El dominio C-terminal es similar a las proteínas GAP conocidas, y un dominio central es homólogo a un represor transcripcional.
Conclusiones:
- p190 posee características estructurales que sugieren una doble funcionalidad en la regulación de la GTPasa y la represión transcripcional.
- p190 puede actuar como un mediador de señalización, transduciendo las señales de la proteína activadora de ras GTPasa al núcleo.
- Esta interacción podría influir en la expresión de genes celulares específicos, afectando los procesos celulares.
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