Maximilian Klamke (Rheinische Friedrich-Wilhelms-Universität Bonn)
Maximilian Klamke's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Bonn University in the year 2025 with the title:
Mapping the Arabidopsis NADP-malic enzyme 1 protein interaction network via co-immunoprecipitation
The thesis demonstrates ABA‑ and drought‑responsiveness of NADP‑ME1 in Arabidopsis using expression analysis and confocal microscopy. Furthermore, it established a foundational framework, via co‑immunoprecipitation, suggesting putative interactions with other cytosolic proteins and a potential involvement in redox homeostasis.
Malic enzymes catalyze the reversible conversion of malate to pyruvate, CO₂, and NAD(P)H. Although NADP-ME1 appears enzymatically inactive in situ,it is thought to be implicated in plant stress adaptation. This study examines NADP-ME1’s role in drought and ABA-induced stress using GFP-based confocal microscopy and co-immunoprecipitation coupled with mass spectrometry. Expression analyses demonstrate strong transcriptional and translational responsiveness to both conditions. Additionally, confocal microscopy revealed NADP-ME1 expression in root tips after ABA treatment, correlating with the ABA-insensitive phenotype of nadp-me1 mutants and a conserved ABA-responsive promoter motif. This suggests a role for NADP-ME1 in ABA-mediated root growth regulation and drought adaptation. Mass spectrometry identified putative heteromeric interactions between NADP-ME1 and other cytosolic proteins, notably associations with antioxidant proteins such as APX1 and CAT1, pointing to roles in redox homeostasis and ROS regulation. While these findings provide a framework for understanding NADP-ME1’s contribution to stress resilience, the physiological relevance of the protein interactions remains elusive. Future work should explore the promoter motif function, confirm protein interactions through BiFC and Y2H, and assess NADP-ME1’s role across broader phytohormonal and abiotic stress networks.
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Maximilian Klamke conducted this work at the IZMB as part of Ying Fu's PhD project in the research group of Prof. Dr. Veronica Maurino.