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RETRACTADO: Un péptido sulfatado de tipo I secretado desencadena inmunidad innata mediada por XA21 mediada por XA21
Sang-Won Lee1, Sang-Wook Han, Malinee Sririyanum
1Department of Plant Pathology, University of California, Davis, CA 95616, USA.
Science (New York, N.Y.)
|November 7, 2009
Resumen
Las plantas de arroz poseen el receptor inmune XA21, que reconoce una proteína bacteriana llamada Ax21. Un péptido sulfatado específico de Ax21 es esencial para activar esta inmunidad vegetal contra Xanthomonas oryzae.
Área de la Ciencia:
- Patología vegetal patología vegetal.
- Biología molecular La biología molecular.
- Inmunología Inmunología.
Sus antecedentes:
- El gen Xa21 del arroz proporciona resistencia contra Xanthomonas oryzae pv. oryzae (Xoo). también conocido como oryzae (Xoo).
- La identificación de los componentes moleculares involucrados en la inmunidad mediada por XA21 es crucial para comprender los mecanismos de defensa de las plantas.
Objetivo del estudio:
- Para identificar la molécula específica de Xoo que desencadena la inmunidad mediada por XA21.
- Para dilucidar la base molecular del reconocimiento XA21 de su ligando bacteriano.
Principales métodos:
- Se utilizó cromatografía líquida-espectrometría de masas en tándem (LC-MS/MS) para analizar el supernatante Xoo.
- Se realizaron ensayos de coinmunoprecipitación para estudiar las interacciones de las proteínas.
- Los péptidos sintéticos derivados de la proteína identificada fueron probados para la actividad biológica.
Principales resultados:
- Una proteína de 194 aminoácidos, designada Ax21, fue identificada como el componente activo en los supernatantes Xoo.
- Un péptido sulfatado de 17 aminoácidos (axY(S) 22 del extremo N de Ax21 fue suficiente para provocar inmunidad mediada por XA21.
- La sulfatación del péptido por tirosina fue esencial para su actividad biológica.
- XA21 se une directamente al péptido axY(S) 22 , como se muestra por la coinmunoprecipitación.
- El péptido axY(S) 22 se conserva en todas las especies de Xanthomonas.
Conclusiones:
- Ax21 funciona como un patrón molecular asociado al patógeno (PAMP).
- XA21 actúa como un receptor de reconocimiento de patrones (PRR) que reconoce específicamente el péptido axY(S) 22 sulfatado.
- Este hallazgo aclara la interacción molecular subyacente a la inmunidad vegetal basada en XA21 contra patógenos bacterianos.
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