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Intracellular Refolding Assay
Published on: January 24, 2012
Interacción específica entre el antígeno tumoral celular p53 y las principales proteínas de choque térmico
Nature
|March 13, 1986
Resumen
La proteína supresora de tumores p53 forma complejos con las proteínas de choque térmico (HSP70 y HSP68). Esta interacción estabiliza p53 y puede desempeñar un papel en el desarrollo del cáncer y la transformación viral.
Área de la Ciencia:
- Biología molecular La biología molecular.
- Oncología Oncología.
- Virología Virología.
Sus antecedentes:
- La proteína p53 está involucrada en la transformación neoplásica.
- p53 forma complejos con el antígeno T grande del virus simio 40 (SV40), potencialmente estabilizando p53 y ayudando a la transformación mediada por SV40.
- Se observan niveles elevados y estabilizados de p53 en células no transformadas en SV40.
Objetivo del estudio:
- Para investigar la naturaleza de la interacción entre p53 y un polipéptido co-precipitado (p68).
- Para identificar el polipéptido p68 y su relación con la estabilización de p53.
- Para examinar la formación del complejo p53 con proteínas de choque térmico en diversas condiciones.
Principales métodos:
- Co-precipitación mediante el uso de anticuerpos monoclonales anti-p53.
- Sedimentación del gradiente de sacarosa para analizar propiedades complejas.
- La disociación in vitro de los complejos proteicos.
- Análisis de los niveles de proteínas en las líneas celulares de sobreproducción de p53 y después de un choque térmico.
Principales resultados:
- La co-precipitación de p68 con anticuerpos anti-p53 representa un complejo específico entre p53 y p68.
- Los sedimentos del complejo p53-p68 como un pico amplio (10-14S) y pueden ser disociados in vitro.
- p68 se identifica como el cognado de la proteína de choque térmico 70 (HSP70), que se encuentra en niveles elevados en las células con sobreproducción de p53.
- p53 forma un complejo con la proteína de choque térmico 68 (HSP68) en las células que sobreproducen p53 tras el choque térmico.
Conclusiones:
- p53 específicamente complejos con HSP70 y HSP68.8.
- La estabilización de p53 observada en ciertas células transformadas puede estar mediada por su interacción con las proteínas de choque térmico.
- Estos hallazgos proporcionan información sobre los mecanismos de regulación de la p53 y su papel en la transformación celular.
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