WP1-1 Increased Cellulose Formation in Poplar by Modulating Membrane Trafficking
PI – Prof. Dr. Ingo Heilmann (Dept. of Plant Biochemistry)
Institute of Biochemistry and Biotechnology, Faculty of Science 1, MLU
Postdocs – Dr. Irene Stenzel and Vera Wagner
Plant cell walls, primarily composed of cellulose, are a valuable raw material with significant potential for biotechnological innovation. Understanding and optimizing their formation is crucial for improving cellulose yields. Cell wall synthesis is a complex process involving cellulose synthase complexes, which are membrane-embedded proteins that deposit cellulose along intracellular cytoskeletal tracks. The number and activity of these complexes depend heavily on their trafficking to and from the plasma membrane, which is regulated by specific membrane lipids. Recent research in Arabidopsis thaliana has identified the phospholipid PIP2 as a novel regulator of cellulose synthase abundance, with PI4P 5-kinases PIP5K1 and PIP5K2 playing key roles in PIP2 production. Double mutants lacking both kinases produce more cell wall material and longer cellulose fibers. Building on these findings, the current project seeks to identify corresponding PI4P 5-kinase genes in poplar and engineer transgenic lines to modify membrane lipid composition and potentially enhance cellulose production.
WP1-2 Bioactive Plant Compounds from Olive Leaves as Potential Pharmaceuticals
PI – Prof. Dr. Wim Wätjen (Dept. of Biofunctionality of Secondary Plant Compounds)
Institute of Agricultural and Nutritional Sciences, Faculty of Science 3, MLU
The use of plant-derived secondary metabolites for pharmaceutical purposes has a long historical precedent and remains highly relevant today. A key goal in this field is to identify raw plant materials that are not only pharmacologically interesting but also cost-effective and readily available. Olive leaves, a byproduct of the olive harvest that amounts to millions of tons annually, are rich in bioactive compounds such as oleuropein and oleanolic acid, along with many lesser-studied substances. This project investigates the biological activity of various olive leaf extracts and individual or combined compounds in a simple in vivo model system using the nematode Caenorhabditis elegans. The focus is on evaluating antioxidant, life-extending, and neuroprotective effects. Additionally, modified forms of these plant substances, including encapsulated or derivatized variants with potentially higher bioavailability, are being tested. Compounds or extracts that demonstrate high bioactivity, such as significant lifespan extension, will undergo further molecular analysis to pinpoint their mechanisms of action. Given their promising effects, such bioactive compounds hold potential for applications in the pharmaceutical and cosmetics industries. The overarching aim of this exploratory project is to optimize the extraction and isolation of valuable compounds from olive leaves, test their biological effects in the C. elegans model, and identify new candidate substances through metabolomic analysis.
WP1-3 New Molecular Targets for Optimizing Benzylisoquinoline Alkaloid Formation in Opium Poppy
PI – Dr. Mareike Heilmann (Department of Plant Biochemistry)
Institute of Biochemistry and Biotechnology, Faculty of Science 1, MLU
Postdocs – Johanna Uhlenberg and Marie Lebescond
Benzylisoquinoline alkaloids (BIAs) are a vital class of secondary plant metabolites that include medically significant compounds such as morphine and codeine, known for their analgesic and anti-inflammatory properties. Due to the complexity and cost of their synthetic production, these compounds are primarily sourced from the opium poppy (Papaver somniferum L.). BIA production in poppies is typically triggered by environmental stressors like wounding or salinity, yet the molecular mechanisms regulating BIA biosynthesis and composition remain poorly understood. Insights gained from studies in Arabidopsis thaliana suggest that stress-induced BIA formation involves phospholipid-based signaling pathways, which also mediate plant defense responses. Building on this knowledge, previous work by the research group has shown that pharmacological modulation of signaling lipid metabolism in P. somniferum can enhance BIA production, even in the absence of stress. Notably, this manipulation led to an increase in the formation of medically valuable morphine at the expense of less pharmacologically relevant alkaloids. These findings provide a strong proof of concept that targeted alterations in signaling lipid metabolism can optimize BIA output. To fully harness this potential, the project aims to identify and characterize key enzymes involved in the signaling lipid pathways of P. somniferum, assess their effects on gene expression and BIA biosynthesis through transient protoplast transformation, and ultimately generate transgenic poppy plants with modified signaling pathways to boost the yield and specificity of medically relevant BIAs.
WP1-4 MAGIC-Pangenome – Establishing a pangenome of the eight donors of the MAGIC wheat population WM-800 to select genes controlling nitrogen use efficiency and baking quality for wheat breeding
PIs – Prof. Dr. Klaus Pillen/Dr. Thomas Schmutzer/Anne-Kathrin Pfrieme (Department of Plant Breeding)
Institute of Agricultural and Nutritional Sciences, Faculty of Science 3, MLU
PhD student – Marvin Behnke
Wheat is among the most important crops world-wide. This is also due to its excellent baking quality properties, controlled by the availability and composition of nitrogen and grain proteins. The current level of precision genomics allows to carry out comparative analyses with high-quality genomic reference sequences that almost completely capture the genetic diversity present in a species, for example, through SNPs, structural variations and translocations. This allows complex traits such as baking quality properties to be described with high precision. However, in hexaploid wheat with 21 chromosome pairs and a genome size of 16 gigabases, the establishment of such a pangenomic resource is extremely complex due to polyploidy and the very high repeat content (>85%) of the wheat genome. Our MAGIC-Pangenome project aims to close this gap for the multiparental wheat population WM-800 through a pangenomic characterization of the eight crossing parents of this population. For this purpose, long-read sequencing and chromatin conformation capture methods, optimized for wheat, will be applied. Subsequently, the constructed pangenomic resource will be used in multimodal transcriptome studies. In addition, selected WM-800 lines will be analyzed under nitrogen stress in order to elucidate in a pangenomic context the role of candidate genes on nitrogen utilization and baking quality formation, for example, the nitrogen transporter genes NRT1 and NRT2 and the NAC transcription factor gene NAM 1.
WP1-5 Using “plant tears” as a source of recombinant proteins
PI – Dr. Martin Schattat (Department of Plant Physiology)
Institute of Biology, Faculty of Science 1, MLU
PhD student – Simon Ortmann
This project aims to establish plant guttation fluid, watery droplets naturally secreted from leaf edges under high humidity, as a low-cost, low-tech platform for producing recombinant proteins. Building on earlier proof-of-concept studies in Arabidopsis thaliana, we will adapt this method to high-guttation plant species like tomato and Brassica rapa. Recombinant proteins are vital for industrial, nutritional, and medical applications, but traditional production using microbes or animal cells is expensive and requires strict contamination controls. Plants, by contrast, offer a sustainable and economical alternative, though purification of intracellular proteins remains a major challenge. To address this, our approach uses guttation fluid, which is naturally sterile, easy to access, and low in background proteins, making it ideal for direct recombinant protein recovery. Previous work demonstrated that fluorescent protein mCherry could accumulate in guttation fluid at purities comparable to bacterial expression systems. However, other proteins, including lactoferrin, IL-6, MPT64, and PF4, showed poor stability, likely due to degradation by endogenous proteases. To overcome this, we will scale up protein expression in tomato and B. rapa and improve protein stability through protease modulation, expression of protease inhibitors, genome engineering, and synthetic biology tools such as hydathode-specific promoters and feedback loops for precise control. Once optimized, this platform will allow greenhouse-based cultivation of transgenic plants, controlled induction of guttation through humidity regulation, continuous harvesting of recombinant proteins, and streamlined purification through single-step affinity methods.
WP1-6 Optimizing plant productivity through targeted protein storage in plastids
PI – Dr. Bationa Bennewitz (Department of Plant Physiology)
Institute of Biology, Faculty of Science 1, MLU
The global demand for protein-rich foods is increasing with the growing population, necessitating innovative approaches to increasing plant productivity. To increase the amount of protein in plant storage tissues, not only the expression rate of genes for such dietary proteins is important, but also stable subcellular storage in suitable cell organelles. The typical protein storage organelles in the cell are the so-called “protein bodies” or “protein vacuoles,” small vesicle-like structures that belong to the endomembrane system and are subject to its internal cellular regulation. An alternative plant storage organelle that does not belong to the endomembrane system and is therefore not subject to its regulation are the plastids (e.g., chloroplasts). These are not only essential for photosynthesis, and thus for overall plant productivity, but, in the form of amyloplasts, also serve for the permanent storage of starch. Plastids are considerably larger than “protein bodies” and potentially have a much greater protein storage capacity. The aim of the project is therefore to utilize plastids as an additional compartment for protein storage. This requires the synthesis of the dietary proteins to be stored as precursor polypeptides together with suitable plastid transport signals (transit peptides) in the plant cells. Our research group has many years of experience in the fields of plant transformation, gene expression, and intracellular protein transport, with a focus on protein import into plastids. This provides us with a large number of different transit peptides that can differ in their organelle specificity, transport efficiency, and suitability for different dietary proteins. We propose to initially conduct the experiments using one monocotyledonous (Hordeum vulgare, barley) and one dicotyledonous crop plant (Solanum tuberosum, potato) as model organisms.