Fröschel Lab (now at Bot II, University of Würzburg)
Since 2016 Post-doc at the University of Würzburg, Department of Pharmaceutical Biology
2016 PhD (Dr. rer. nat. Biologie) about cell-type specific expressed genes in the Arabidopsis-root after inoculation with pathogenic and mutualistic microorganisms
2012-2015 Researcher at the University of Würzburg
2006-2012 Biology studies (Diplom) at the Julius-Maximilians-University Würzburg with internship in Canada
Alexander Marsell (PhD student)
2020 Master thesis at the Julius-Maximilians-University Würzburg about pathogen-dependent translational control of gene expression in the Arabidopsis root
The root endodermis as a barrier against abiotic stress and microbial invasion
The endodermis is a cell-layer of the root that separates the inner vasculature from the outer cortex. Although it is a thin cell-layer, it is of central importance. Hydrophobic cell wall reinforcements, such as the Casparian strip (CS) or suberin deposits, seal the endodermal extracellular space and block free diffusion. This allows a selective uptake of water and nutrients across the plasma membrane and controls the bidirectional flow to the vasculature. To date, little is known about how the structures surrounding the endodermal cells protect the root from microbial invasion. It is essential for the plant to keep microbes from the xylem vessels, where they can otherwise easily spread systemically with the water flow. Using the highly specialized and morphologically well-defined endodermis, we address the question of how barrier assembly is regulated and adapted to different stress situations. We decipher multicomponent networks that control endodermis-specific gene expression and distinguish between transcriptional (e.g., characterization of cell type-specific transcription factors) and post-transcriptional (e.g., cell type-specific translational adaptation) control mechanisms. Knowing more about how endodermal features arise will provide new opportunities for breeding more resilient crop plants.
Literature: Fröschel et al., Cell Host and Microbe 2021
Researcher: Christian Fröschel
The vascular fungus Verticillium as a model pathogen to study root-microbe interactions
The rhizosphere harbors a highly complex microbial community that is in close contact with plant roots. Yet, just a few mechanisms are known by which roots defend against microorganisms. New knowledge of root-microbe interactions is required to develop novel strategies in agriculture and reduce crop losses. We use fungi of the genus Verticillium as model organisms to study interactions of the root with soil-borne microbes. These fungi are characterized by an unusual colonization strategy: after the hyphae have reached the host roots, they traverse all concentric cell layers and penetrate the central cylinder. Once there, the fungus spreads to the above-ground plant parts via the water vessels. The infected host plant suffers growth defects and develops premature senescence, chlorosis or wilting. We have established several infection systems and use Arabidopsis, oilseed rape as well as tomato as model plants to study how the fungi spread in their host plants from the roots to the shoot. We are investigating how the plant defends itself against the fungus and how the fungus can manipulate the plant's immune system utilizing effectors.
Literature: Fröschel, Plant Methods 2021
Researchers: Christian Fröschel, Alexander Marsell
Fröschel C, In-depth evaluation of root infection systems using the vascular fungus Verticillium longisporum as soil-borne model pathogen. bioRxiv 2020.12.28.424556, doi: https://doi.org/10.110/2020.12.28.424556.
Fröschel C, Komorek J, Attard A, Marsell A, Lopez-Arboleda WA, Le Berre J, Wolf E, Geldner N, Waller F, Korte A, Dröge-Laser W. Plant roots employ cell-layer-specific programs to respond to pathogenic and beneficial microbes. Cell Host Microbe. 2021 Feb 10;29(2):299-310.e7. doi: 10.1016/j.chom.2020.11.014. Epub 2020 Dec 29. PMID: 33378688.
Fröschel C, Iven T, Walper E, Bachmann V, Weiste C, Dröge-Laser W. A Gain-of-Function Screen Reveals Redundant ERF Transcription Factors Providing Opportunities for Resistance Breeding Toward the Vascular Fungal Pathogen Verticillium longisporum. Mol Plant Microbe Interact. 2019 Sep;32(9):1095-1109. doi: 10.1094/MPMI-02-19-0055-R. Epub 2019 Jul 30. PMID: 31365325.
Weiste C, Pedrotti L, Selvanayagam J, Muralidhara P, Fröschel C, Novák O, Ljung K, Hanson J, Dröge-Laser W. The Arabidopsis bZIP11 transcription factor links low-energy signalling to auxin-mediated control of primary root growth. PLoS Genet. 2017 Feb 3;13(2):e1006607. doi: 10.1371/journal.pgen.1006607. PMID: 28158182; PMCID: PMC5315408.