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La señalización sistémica y la aclimatación en respuesta al exceso de energía de excitación en Arabidopsis
S Karpinski1, H Reynolds, B Karpinska
1Department of Forest Genetics and Plant Physiology, Faculty of Forestry, Swedish University of Agricultural Sciences, SE-901 83 Umeâ, Sweden. stanislaw.karpinski@genfys.slu.se
Science (New York, N.Y.)
|April 24, 1999
Resumen
Las plantas pueden comunicar sistemáticamente el exceso de estrés lumínico a las hojas no expuestas, desencadenando defensas antioxidantes protectoras. Esta aclimatación sistémica adquirida ayuda a las plantas a defenderse contra futuros daños fotooxidativos.
Área de la Ciencia:
- Fisiología vegetal Fisiología vegetal
- Biología molecular La biología molecular.
- Respuesta al estrés ambiental en respuesta al estrés ambiental.
Sus antecedentes:
- Las plantas terrestres exhiben sofisticados mecanismos de aclimatación a los cambios ambientales.
- La fotosíntesis es vulnerable al exceso de luz, lo que lleva al estrés fotooxidativo.
- La señalización sistémica en las plantas es crucial para coordinar las respuestas.
Objetivo del estudio:
- Para investigar la comunicación sistémica del exceso de estrés lumínico en Arabidopsis.
- Identificar los componentes clave involucrados en la aclimatación sistémica adquirida.
- Para entender cómo las hojas no expuestas son alertadas al estrés en otras partes de la planta.
Principales métodos:
- Las plantas de Arabidopsis fueron parcialmente expuestas al exceso de luz.
- Se monitorearon cambios sistémicos en el estado redox cerca del fotosistema II.
- Se analizaron los niveles de peróxido de hidrógeno y la expresión génica antioxidante en hojas no expuestas.
Principales resultados:
- El exceso parcial de exposición a la luz indujo la aclimatación sistémica en hojas no expuestas.
- Se observaron cambios sistémicos de redox y acumulación de peróxido de hidrógeno.
- La upregulación de las defensas antioxidantes ocurrió en tejidos distantes y no expuestos.
Conclusiones:
- Las plantas poseen un mecanismo para la comunicación sistémica del exceso de energía de excitación.
- Esta señalización permite una defensa preventiva contra el estrés fotooxidativo.
- La aclimatación adquirida sistémica está mediada por señales redox y inducción de antioxidantes.
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