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El sustrato de 36 kilodaltones de pp60v-src es miristilado de una manera sensible a la transformación
Science (New York, N.Y.)
|November 1, 1985
Resumen
Una proteína de 36 kD, un sustrato para la quinasa pp60v-src, se modifica con ácido mirístico a través de un enlace de amida. Esta miristoilación se reduce en las células transformadas por el virus del sarcoma de Rous.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Biología celular Biología celular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- pp60v-src quinasa es una enzima clave en la señalización celular.
- La identificación de sus sustratos es crucial para comprender los procesos celulares.
- Una proteína de 34-39 kD es un sustrato intracelular primario para la quinasa pp60v-src.
Objetivo del estudio:
- Para investigar la naturaleza de la modificación covalente de la proteína de 36 kD.
- Para determinar si el ácido mirístico está unido covalentemente a la proteína de 36 kD.
- Para examinar los cambios en esta modificación en las células transformadas por el virus del sarcoma de Rous.
Principales métodos:
- Incubación de fibroblastos de embriones de pollo (CEF) con ácido [3H] mirístico.
- Análisis mediante electroforesis en gel de dodecilo sulfato de sodio-poliacrilamida (SDS-PAGE) en una y dos dimensiones.
- Pruebas de solubilidad cloroformo-metanol y hidrólisis de hidroxilamina.
Principales resultados:
- La proteína de 36 kD incorporó ácido mirístico unido covalentemente.
- El enlace era resistente a la hidroxilamina, lo que sugiere un enlace amídico.
- La misristoilación de la proteína de 36 kD se redujo hasta en un 45% en el CEF transformado por el virus del sarcoma de Rous en comparación con las células normales.
Conclusiones:
- La proteína de 36 kD es miristoilada a través de un enlace amídico.
- Esta miristoilación se reduce significativamente en las células transformadas por el virus del sarcoma de Rous.
- Los hallazgos proporcionan información sobre la modificación del sustrato de la quinasa pp60v-src y sus alteraciones en la transformación viral.
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