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Degradación del retículo endoplasmático: eliminación de las proteínas recién sintetizadas
J Lippincott-Schwartz1, J S Bonifacino, L C Yuan
1Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, Bethesda, Maryland 20892.
Cell
|July 15, 1988
Resumen
Las subunidades recientemente sintetizadas del receptor de células T (TCR) se degradan rápidamente a través de una vía pre-Golgi vinculada al retículo endoplasmático (ER). Esta vía de degradación asociada a la ER elimina los complejos proteicos incompletos de las células.
Área de la Ciencia:
- Biología celular Biología celular.
- Inmunología Inmunología.
- La degradación de las proteínas.
Sus antecedentes:
- Las subunidades recientemente sintetizadas del receptor de células T (TCR) requieren un ensamblaje adecuado para funcionar.
- Las vías de degradación de las proteínas son cruciales para la homeostasis celular y el control de calidad.
Objetivo del estudio:
- Caracterizar una nueva vía proteolítica involucrada en la degradación de las subunidades del receptor de células T (TCR).
- Para determinar la ubicación celular y las características de esta vía de degradación.
Principales métodos:
- Análisis bioquímicos para estudiar la cinética de la degradación de las proteínas.
- Técnicas morfológicas para identificar el sitio de degradación.
- El uso de ionóforos para interrumpir el transporte de TCR.
- Análisis de la degradación de la subunidad TCR en fibroblastos y células T transfectadas.
Principales resultados:
- Una vía de degradación asociada al retículo endoplasmático (ER) pre-Golgi degrada rápidamente las subunidades TCR recién sintetizadas.
- Esta vía es distinta de la degradación lisosomal y funciona incluso cuando el transporte ER-a-Golgi está bloqueado.
- La vía ER es la ruta principal para la degradación de cadenas alfa TCR sin ensamblar y complejos alfa-beta.
- Todas las cadenas alfa, beta y delta de TCR recién sintetizadas se degradan a través de esta vía en las células T tratadas con ionóforos.
Conclusiones:
- La vía de degradación asociada a la ER juega un papel importante en la eliminación de complejos de proteínas de membrana mal ensamblados de la vía secretora.
- Esta vía es esencial para el control de calidad del ensamblaje y la función del receptor de células T (TCR).
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