Impact of crosstalk phenomena on the defense cis-regulatory landscape in Arabidopsis visualized with DNase-seq footprinting.

为了理解转录因子和它们的同源顺式元件之间的大量可能的组合相互作用如何协调植物激素信号通路，需要一个全面的顺式调控图景。这项提案要求提供资金，利用DNase-Seq足迹技术动态绘制模式植物拟南芥体内TF的足迹图，重点放在防御反应中的激素串扰。在病原体侵染时，植物从头开始合成称为植物激素的小信号分子，以建立适当的免疫状态。根据攻击者的生活方式，不同的荷尔蒙被用来启动适当的防御反应。虽然水杨酸(SA)的产生是为了有效地对抗生物营养性病原体，但茉莉酸(JA)和乙烯(ET)的产生是对抗坏死性病原体的关键。在不同生活方式的多个病原体同时侵染或病原体诱导的防御激素稳态被破坏的情况下，植物需要激素途径之间有效的串扰机制来微调它们的防御努力，避免适应性损失。对防御串扰机制的机械论见解仍然有限。因此，为了阐明JA、ET和SA信号之间的串扰现象是如何在Tf水平上执行的，该项目将首次在全基因组水平上动态调查不同串扰条件下的顺式调控结构。

To understand how the plethora of possible combinatorial interplays between transcription factors (TFs) and their cognate cis-elements coordinates plant hormone signaling pathways, a comprehensive view of the cis-regulatory landscape is required. This proposal requests funding for the dynamic mapping of TF in vivo footprints in the model plant Arabidopsis thaliana utilizing DNase-seq footprinting with an emphasis on hormone crosstalk in defense responses. Plants de novo synthesize small signaling molecules called plant hormones upon pathogen infection in order to establish an adequate status of immunity. Depending on the lifestyle of the attacker, different hormones are employed to initiate the appropriate defense responses. Whereas salicylic acid (SA) is produced to effectively counteract biotrophic pathogens, the production of jasmonic acid (JA) and ethylene (ET) is essential to combat against necrotrophic pathogens. In case of concomitant infection of multiple pathogens with different lifestyles or pathogen-induced disturbances of the defense hormone homeostasis, plants require efficient crosstalk mechanisms between the hormone pathways to fine-tune their defense efforts and to avoid fitness losses. Mechanistic insights into the defense crosstalk machinery are still limited. To elucidate therefore how crosstalk phenomena between JA, ET and SA signaling are executed on the TF level, this project will generate the first dynamic surveys of the cis-regulatory architecture at the whole genome-level under different crosstalk conditions.