INTERACTION OF PHYTOCHROME AND JASMONATE SIGNALING IN THE REGULATION OF GROWTH AND DEFENSE RESPONSES

BALLARE CARLOS L

Montpellier

Simposio; International Plant Molecular Biology Congress; 2018

IPMB

INTERACTION OF PHYTOCHROME AND JASMONATE SIGNALING IN THE REGULATION OF GROWTH AND DEFENSE RESPONSES Carlos L. BallaréPlants detect and respond to the proximity of competitors using light signals perceived by informational photoreceptors. A low red to far-red (R:FR) ratio in the canopy light is a signal of competition that is sensed by phytochrome B (phyB). Low R:FR ratios increase the synthesis of growth-related hormones, including auxin and gibberellins, which allows plants to rapidly elongate their shoots and avoid being shaded by their neighbors. Recent research demonstrates that phyB is also an important modulator of the two principal hormonal pathways that regulate plant immunity against herbivores and pathogens, i.e. the jasmonic-acid (JA) and the salicylic-acid pathways (SA). Low R:FR ratios down-regulate JA-induced defense responses. This down-regulation is thought to help the plant to efficiently redirect resources from defense to rapid growth under conditions of intense competition. In this presentation, I will discuss recent advances in the understanding of the mechanisms that link phyB with JA signaling and metabolism, and explore their functional implications. Unveiling the molecular links between photoreceptors and the hormonal regulators of plant immunity is important to generate a mechanistic framework to understand how plants deal with resource allocation trade-offs under natural conditions.