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La comunicación intercelular y la conjugación están mediadas por los sistemas de secreción ESX en las micobacterias
Todd A Gray1,2, Ryan R Clark3, Nathalie Boucher3
1Wadsworth Center, New York State Department of Health, P.O. Box 22002, Albany, NY 12201-2002, USA. todd.gray@health.ny.gov keith.derbyshire@health.ny.gov.
Science (New York, N.Y.)
|November 16, 2016
Resumen
Mycobacterium smegmatis utiliza el sistema de secreción ESX-1 para controlar la expresión de ESX-4, facilitando la comunicación intercelular y la transferencia de ADN durante la conjugación bacteriana.
Área de la Ciencia:
- Microbiología
- Genética bacteriana
- Comunicación entre células
Sus antecedentes:
- La comunicación intercelular es vital para las comunidades bacterianas, a menudo mediada por sistemas de secreción.
- Esta comunicación no se ha caracterizado previamente en las micobacterias.
- El sistema de secreción ESX es un mediador conocido de las interacciones bacterianas.
Objetivo del estudio:
- Para investigar la comunicación entre las células en Mycobacterium smegmatis.
- Para determinar el papel del sistema de secreción ESX-4 en la conjugación micobacteriana.
- Para aclarar la relación reguladora entre los sistemas de secreción ESX-1 y ESX-4.
Principales métodos:
- Se investigó la función de ESX-4 en la actividad del receptor de Mycobacterium smegmatis.
- Analizó la regulación transcripcional de los genes esx4 en diferentes condiciones de cocultura.
- Utilizó cepas mutantes del aparato de secreción ESX-1 en células donantes y receptoras.
- Actividad ESX-1 correlacionada con las eficiencias de transferencia de ADN conyugal.
Principales resultados:
- ESX-4 es esencial para la actividad del receptor conyugal en Mycobacterium smegmatis.
- La transcripción de los genes esx4 requiere cocultivo con una cepa donante y un aparato ESX-1 funcional.
- La mutación del aparato ESX-1 del donante amplifica la respuesta transcripcional esx4 en el receptor.
- La comunicación intercelular mediada por ESX-1 regula la expresión de ESX-4.
Conclusiones:
- La comunicación intercelular a través del sistema de secreción ESX-1 controla la expresión de su progenitor evolutivo, ESX-4.
- Esta regulación promueve la conjugación y la transferencia de ADN entre las micobacterias.
- ESX-1 actúa como un regulador de ESX-4, destacando una nueva vía de comunicación en las micobacterias.
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