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Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c
Published on: June 29, 2011
Smac, una proteína mitocondrial que promueve la activación de la caspasa dependiente del citocromo c al eliminar la
1Howard Hughes Medical Institute and Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 75235, USA.
Cell
|August 10, 2000
Resumen
Una nueva proteína mitocondrial, Smac (activador de las caspasas derivado de la segunda mitocondria), promueve la apoptosis mediante la activación de las caspasas. Smac neutraliza las proteínas inhibidoras, mejorando las vías de señalización de la muerte celular programada.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La apoptosis, o muerte celular programada, es un proceso celular crítico.
- La activación de la caspasa es central para la ejecución apoptótica.
- Los inhibidores de las proteínas de la apoptosis (IAP) regulan la actividad de la caspase y previenen la muerte celular.
Objetivo del estudio:
- Para identificar nuevas proteínas involucradas en la activación de la caspasa durante la apoptosis.
- Para aclarar el mecanismo por el cual Smac influye en la vía apoptótica.
Principales métodos:
- Identificación y caracterización de proteínas.
- Análisis de las interacciones proteína-proteína.
- Estudios de localización celular.
- Evaluación del efecto de Smac en la activación de la caspasa y la apoptosis.
Principales resultados:
- Identificación de Smac, una nueva proteína mitocondrial.
- Smac promueve la activación de la caspasa-9 al antagonizar las IAP.
- La localización mitocondrial y la escisión del péptido de señal son esenciales para la función pro-apoptótica de Smac.
- La sobreexpresión de Smac sensibiliza a las células a los estímulos apoptóticos.
Conclusiones:
- Smac es un mediador clave de la apoptosis, que actúa aguas abajo de la permeabilización de la membrana externa mitocondrial.
- Smac funciona de manera similar al citocromo c en la promoción de la activación de la caspasa.
- Smac representa un nuevo objetivo para la modulación de la apoptosis.
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