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Examining BCL-2 Family Function with Large Unilamellar Vesicles
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Viajando Bax y hacia adelante desde las mitocondrias para controlar la apoptosis
Maria Eugenia Soriano1, Luca Scorrano
1Dulbecco-Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy.
Cell
|April 5, 2011
Resumen
Las proteínas antiapoptóticas Bcl-2 previenen la muerte celular mediante la inhibición de proteínas pro-muerte como Bax. Una nueva investigación muestra que Bax y Bcl-xL interactúan en las mitocondrias, luego se mueven al citosol para bloquear la muerte celular.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología molecular La biología molecular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las proteínas antiapoptóticas del linfoma de células B 2 (Bcl-2) residen en las mitocondrias, inhibiendo las proteínas prodeath como Bax, que se encuentra principalmente en el citosol.
- La permeabilización de la membrana externa mitocondrial (MOMP) es un paso crítico en la apoptosis, regulada por el equilibrio entre las proteínas Bcl-2 y las proteínas proapoptóticas.
Objetivo del estudio:
- Para investigar la interacción entre Bax y Bcl-xL.
- Para determinar la ubicación y el efecto de esta interacción en la integridad mitocondrial.
Principales métodos:
- Estudios de interacción de las proteínas de la superficie mitocondrial.
- Pruebas de retrotranslocación.
- Análisis de la permeabilización mitocondrial.
Principales resultados:
- Se observó que Bax y Bcl-xL interactúan en la superficie mitocondrial.
- El complejo Bax-Bcl-xL retrotranslocado al citosol.
- Esta retrotranslocación evitó efectivamente la permeabilización mitocondrial inducida por Bax.
Conclusiones:
- La interacción y posterior retrotranslocación de Bax y Bcl-xL representan un nuevo mecanismo para regular la apoptosis mitocondrial.
- Este hallazgo proporciona nuevos conocimientos sobre la compleja interacción de las proteínas de la familia Bcl-2 en las vías de muerte celular.
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