PhD Student

Plants cannot run away from pathogens, so they rely on a sophisticated immune system to detect and respond to danger. One fascinating part of this system involves small signalling molecules called phytocytokines, host-derived peptides that help coordinate immune responses between plant cells.

Recent studies suggest that these peptides play an important role in regulating plant innate immunity. In previous work from our group, we observed the release of several peptides after salicylic acid (SA) treatment into the apoplastic space of Zea mays leaves, which mimics the signalling triggered by biotrophic pathogen infection. Using a Trojan horse approach with recombinant Ustilago maydis, we found that these peptides can activate different downstream pathways, leading either to pro-death or pro-survival responses in plant cells.

My PhD project focuses on understanding how these newly identified phytocytokines are produced and perceived. Specifically, I study how proteases, particularly subtilases, process precursor proteins to generate active peptides, and how these signals are detected by plant surface receptors in neighbouring cells. By investigating how phytocytokines are generated and recognized, my research aims to shed light on the communication network that enables plants to activate effective immune responses. To address these questions, I combine multiple molecular and biochemical approaches, including peptidomics, transcriptomics, Activity-Based Protein Profiling (ABPP), Enzyme-Linked Immunosorbent Assay (ELISA), and genetic tools such as overexpression, gene silencing, and knockdown in three main plant models: Z. mays, Nicotiana benthamiana and Arabidopsis thaliana.

This project is part of the SFB 1403 Cell Death in Immunity, Inflammation and Disease, a collaborative effort to better understand how controlled cell death contributes to defence and health across biological systems.

University of Cologne

CEPLAS / Institiute for Plant Sciences
Chair of Terrestrial Microbiology
Zülpicher Straße 47a
D-50674 Cologne
Tel:  +49 221-470-1960
Fax: +49 221-470-7406
Mail: hlaia@uni-koeln.de