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El efector de Legionella RavZ inhibe la autofagia del huésped a través de la irreversible desconjugación de Atg8
Augustine Choy1, Julia Dancourt, Brian Mugo
1Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA.
Science (New York, N.Y.)
|November 1, 2012
Resumen
Legionella pneumophila inhibe la autofagia de las células huésped utilizando la proteína efector RavZ. RavZ inactiva irreversiblemente las proteínas Atg8, impidiendo la formación de autofagosomas y ayudando a la supervivencia bacteriana.
Área de la Ciencia:
- Biología celular Biología celular.
- Microbiología Microbiología.
- Inmunología Inmunología.
Sus antecedentes:
- La autofagia es un mecanismo de defensa celular contra los patógenos intracelulares.
- La manipulación de patógenos de la autofagia sigue siendo un área de investigación activa.
- Legionella pneumophila es un patógeno intracelular que reside en vacuolas modificadas.
Objetivo del estudio:
- Investigar si los patógenos intracelulares han desarrollado mecanismos para manipular la vía de la autofagia.
- Para identificar los factores bacterianos involucrados en la inhibición de la autofagia por Legionella pneumophila.
Principales métodos:
- Caracterización de la proteína efector bacteriana RavZ de Legionella pneumophila.
- Análisis bioquímicos para determinar la interacción entre las proteínas RavZ y Atg8.
- Análisis de la modificación y la conjugación de la proteína Atg8 en células infectadas.
Principales resultados:
- La proteína efector de la Legionella pneumophila RavZ interfiere directamente con la autofagia.
- RavZ desacopla las proteínas Atg8 de las membranas del autofagosoma mediante la hidrólisis de su enlace amídico.
- Esta inactivación irreversible impide la reconjugación de Atg8 por los factores huésped Atg7 y Atg3.
Conclusiones:
- Los patógenos intracelulares pueden inhibir la autofagia mediante la inactivación irreversible de proteínas clave de la autofagia como Atg8.8.
- RavZ representa un nuevo mecanismo para la manipulación bacteriana de la autofagia del huésped.
- Comprender estos mecanismos es crucial para desarrollar estrategias terapéuticas contra las infecciones por Legionella.
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