0 avis
Leaf-mining by Phyllonorycter blancardella reprograms the host-leaf transcriptome to modulate phytohormones associated with nutrient mobilization and plant defense
Archive ouverte
This study has been supported by the ANR Grant No. ANR-05-JCJC-0203-01 and the Region Centre Project 201000047141. International audience. Phytohormones have long been hypothesized to play a key role in the interactions betweenplant-manipulating organisms and their host–plants such as insect–plant interactions that lead to gallor ‘green-islands’ induction. However, mechanistic understanding of how phytohormones operate inthese plant reconfigurations is lacking due to limited information on the molecular and biochemical phytohormonalmodulation following attack by plant-manipulating insects. In an attempt to fill this gap, thepresent study provides an extensive characterization of how the leaf-miner Phyllonorycter blancardellamodulates the major phytohormones and the transcriptional activity of plant cells in leaves of Malusdomestica.We show here, that cytokinins strongly accumulate in mined tissues despite a weak expressionof plant cytokinin-related genes. Leaf-mining is also associated with enhanced biosynthesis of jasmonicacid precursors but not the active form, a weak alteration of the salicylic acid pathway and a clear inhibitionof the abscisic acid pathway. Our study consolidates previous results suggesting that insects mayproduce and deliver cytokinins to the plant as a strategy to manipulate the physiology of the leaf to createa favorable nutritional environment. We also demonstrate that leaf-mining by P. blancardella leads to astrong reprogramming of the plant phytohormonal balance associated with increased nutrient mobilization,inhibition of leaf senescence and mitigation of plant direct and indirect defense
Consulter en ligne
Suggestions
Du même auteur
