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Los bacteriófagos codifican los factores necesarios para la protección en un mutualismo simbiótico
Kerry M Oliver1, Patrick H Degnan, Martha S Hunter
1Department of Entomology, University of Georgia, Athens, GA 30602, USA. kmoliver@uga.edu
Science (New York, N.Y.)
|August 22, 2009
Resumen
Los bacteriófagos, virus que infectan a las bacterias, son cruciales para el simbionte protector Hamiltonella defensa para defender a los áfidos contra los parasitoides. La pérdida de fagos en estas bacterias compromete la defensa del pulgón.
Área de la Ciencia:
- Microbiología Microbiología.
- Interacciones entre insectos y microbios.
- Biología de los bacteriófagos.
Sus antecedentes:
- Los bacteriófagos a menudo llevan factores de virulencia para las bacterias patógenas.
- El papel de los bacteriófagos en las bacterias simbióticas, particularmente en la concesión de beneficios al huésped, se entiende menos.
- Hamiltonella defensa es un simbionte bacteriano hereditario que protege a los áfidos (Acyrthosiphon pisum) de las avispas parasitarias (Aphidius ervi).
Objetivo del estudio:
- Investigar el papel de los bacteriófagos en el fenotipo protector conferido por Hamiltonella defensa a su huésped áfido.
- Para determinar si los bacteriófagos son esenciales para la defensa del pulgón contra el ataque parasitario.
Principales métodos:
- Experimentos controlados de antecedentes genéticos con líneas clonales de áfidos infectados con Hamiltonella defensa.
- Monitoreo de la pérdida de fagos dentro de las poblaciones de simbiontes en laboratorio.
- Evaluación de la susceptibilidad de los áfidos al ataque parasitario después de la pérdida de fagos.
Principales resultados:
- Se requiere un bacteriófago codificador de toxinas dentro de Hamiltonella defensa para el fenotipo protector contra los parasitoides.
- La pérdida de fagos se observó repetidamente en líneas de áfidos mantenidas en laboratorio.
- La pérdida del bacteriófago resultó en una mayor susceptibilidad de los pulgones al ataque parasitario.
Conclusiones:
- Los bacteriófagos pueden actuar como vectores de rasgos ecológicamente importantes, como la defensa contra los parasitoides.
- Los elementos genéticos móviles como los bacteriófagos pueden proporcionar beneficios a los simbiontes bacterianos que se extienden a sus huéspedes animales.
- Los fagos juegan un papel crítico en la mediación de la defensa mediada por simbiontes en insectos huéspedes.
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