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Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes
Published on: September 20, 2013
Un riboswitch de acción trans controla la expresión del regulador de virulencia PrfA en Listeria monocytogenes
Edmund Loh1, Olivier Dussurget, Jonas Gripenland
1Department of Molecular Biology, Umeå University, 90187 Umeå, Sweden.
Cell
|November 17, 2009
Resumen
Dos riboswitches de S-adenosilmetionina (SAM), SreA y SreB, en Listeria monocytogenes pueden funcionar en trans, regulando la expresión del gen de virulencia bacteriana mediante el control del regulador PrfA. Esto revela una nueva clase de ARN no codificantes que vinculan la disponibilidad de nutrientes con la virulencia.
Área de la Ciencia:
- Bacteriología Bacteriología.
- Biología Molecular Biología Molecular
- ARN Biología Biología ARN
Sus antecedentes:
- Los riboswitches son elementos de ARN de acción cis que modulan la expresión génica a través de cambios estructurales inducidos por metabolitos.
- La S-adenosilmetionina (SAM) es un metabolito crucial involucrado en varios procesos celulares.
- La virulencia bacteriana a menudo está regulada por complejas redes genéticas.
Objetivo del estudio:
- Investigar las funciones reguladoras de los riboswitches SAM SreA y SreB en Listeria monocytogenes.
- Para determinar si estos riboswitches pueden funcionar en trans como ARN no codificantes.
- Para aclarar la conexión entre la disponibilidad de nutrientes y la virulencia bacteriana.
Principales métodos:
- Análisis genético de SreA y SreB en Listeria monocytogenes.
- Análisis de la expresión de ARNm y proteínas del regulador de virulencia PrfA.
- Reporter ensayos para evaluar la actividad del riboswitch.
Principales resultados:
- Se encontró que SreA y SreB funcionan en trans, actuando como ARN no codificantes reguladores.
- Estos riboswitches se unen a la región 5' no traducida del ARNm PrfA.
- La eliminación de SreA y SreB condujo a un aumento de los niveles de PrfA y una mayor expresión génica de virulencia.
Conclusiones:
- Los riboswitches SAM SreA y SreB juegan un nuevo papel regulador de acción trans en Listeria monocytogenes.
- Estos riboswitches vinculan los niveles intracelulares de SAM con la regulación de la virulencia bacteriana.
- Se ha identificado una nueva clase de ARN reguladores no codificantes involucrados en la patogénesis bacteriana.
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