Transcriptional Regulation of Systematic Acquired Resistance
Similar to humans, plants have complex, interrelated and functional immune system, which enables them to defend themselves against biotic stresses. Fungi, oomycetes, bacteria, viruses and other micro-organisms pose a threat to food security by infecting vital crops and trees. When a plant is infected by a pathogenic microbe, its immune system responds in many ways in order to prevent further pathogen invasion. Systemic acquired resistance (SAR) is an important type of immune response that allows plants to protect themselves within the entire foliage against pathogen attack. The establishment of SAR is regulated by two key immune-active metabolites, N-hydroxypipecolic acid (NHP) and salicylic acid (SA). After being produced in pathogen-inoculated leaves, they activate the transcription of a whole battery of defense-related genes systemically in the plant.
Our project aims to identify the transcription factors that coordinate the biosynthesis and the signal transduction of NHP and SA in plants during SAR establishment. Recent research suggests that several transcription factors (TF) act consecutively in waves to execute SAR. In our project, we focus on the WRKY class of TF’s which are known to regulate diverse responses in plants related to growth and stress. We have identified and selected particular WRKY´s that show strong transcriptional up-regulation in SAR. By using gas chromatography/mass spectrometry (GC/MS) analysis, qPCR-based expression analyses of the target genes, resistance assays with WRKY knockout mutant plants and chromatin immunoprecipitation (ChIP) assays , we aim at identifying and characterizing WRKY TF´s that regulate the transcriptional response associated with SAR and the biosynthesis of the SAR-activating metabolites NHP and SA.
Starting date: 01.08.2021 / Doctoral Researcher - DAAD GSSP Scholarshipholder
Thesis committee members: Jügen Zeier, Laura Rose
Butt GR, Qayyum ZA, Jones MA. Plant Defence Mechanisms Are Modulated by the Circadian System. Biology (Basel). 2020 Dec 9;9(12):454. doi: 10.3390/biology9120454.