PAMP-triggered genetic reprogramming involves widespread alternative transcription initiation and an immediate transcription factor wave

通讯单位：丹麦哥本哈根大学

背景回顾、提出问题：Immune responses triggered by pathogen-associated molecular patterns (PAMPs) are key to pathogen defense, but drivers and stabilizers of the growth-to-defense genetic reprogramming remain incompletely understood in plants. 

病原菌相关的分子模式引发的免疫反应是病原菌防御的关键，但植物中生长-防御基因重新编程的驱动因素和稳定剂还未完全理解。

研究内容：Here, we report a time-course study of the establishment of PAMP-triggered immunity (PTI) using cap analysis of gene expression (CAGE).

我们利用CAGE构建PAMP触发免疫的时程研究

研究结果：We show that around 15% of all transcription start sites (TSSs) rapidly induced during PTI define alternative transcription initiation events. From these, we identify clear examples of regulatory TSS change via alternative inclusion of target peptides or domains in encoded proteins, or of upstream open reading frames (uORFs) in mRNA leader sequences. We also find that 60% of PAMP-response genes respond earlier than previously thought. In particular, a cluster of rapidly and transiently PAMP-induced genes is enriched in transcription factors whose functions, previously associated with biological processes as diverse as abiotic stress adaptation and stem cell activity, appear to converge on growth restriction. Furthermore, examples of known potentiators of PTI, in one case under direct MAP kinase control, support the notion that the rapidly induced transcription factors could constitute direct links to PTI signaling pathways and drive gene expression changes underlying establishment of the immune state.

该研究发现，在PTI过程中快速诱导的所有转录起始点（TSS），约有15%定义了可选的转录起始事件。从这些中，该研究识别率调控TSS变化的明显例子，通过在编码蛋白中替代的，包括目标肽或结构域，或者在mRNA前导序列中包含上游开放阅读框（uORF）。该研究发现60%的PAMP反应基因比之前认为的更早作反应。特别是，一组快速和短暂的PAMP诱导的基因富含转录因子，这些转录因子以前与各种生物过程相关，如非生物胁迫适应性和干细胞活性，但似乎在生长限制方面收敛。此外，在一个案例中，已知的PTI增强子的例子，直接受到MAP激酶控制，支持快速诱导的转录因子可以构成与 PTI信号通路的直接联系，并驱动潜在的免疫状态建立的基因表达变化的概念。

原文链接：https://academic.oup.com/plcell/advance-article/doi/10.1093/plcell/koac108/6566310?login=true

Journal:The Plants Cell， 

Published data: 11 April 2022