User:Johannes Stuttmann

Contact Info

Some lab members: Johannes Gantner, Jana Ordon and Johannes Stuttmann

• Johannes Stuttmann
• Martin Luther University Halle
• Weinberweg 10
• 06108 Halle (Saale)
• Germany
• Email me through OpenWetWare

Education

• since 2012, junior group leader, Martin Luther University Halle, Germany
• 2008-2012, Postdoc, Max Planck Institute for Plant Breeding Research, Cologne, Germany
• 2004-2007, PhD, CEA Cadarache (University Aix-Marseille II, France)
• 2004, MSc, Martin Luther University Halle, Germany

Research Scope: Plant Innate Immune Signaling and Biotechnology

Our main resarch interest is dedicated to the analysis of plant immunity towards microbial pathogens. Plant immunity is most commonly depicted as a two-layered system. On the outside of the cell, receptors recognize so-called microbe-associated molecular patterns. Intracellularly, immune receptors of the nucleotide-binding/leucine-rich repeat class (NLRs) detect, directly or indirectly, microbial proteins translocated into the host cell cytoplasm during infection. NLRs are modular proteins comprising, according to current understanding, an N-terminal signaling domain (TIR or CC domain), a central activation switch (NB domain) and a C-terminal LRR domain generally determining recognition specificity. We are interested, on the hand, in the mechanistics of TIR domain-containing NLRs: Upon receptor activation, how is a signal initiated and transduced for triggering immune signaling? On the other hand, we analyse the basis and consequences of clashes within the immune system, also referred to as autoimmunity. The induction of autoimmunity is detrimental for plant fitness, and may limit the assembly of beneficial NLRs in a single genetic background, thus representing an important limitation for plant breeding programs. We aim to elucidate by which mechanisms autoimmunity is actually induced, and how "risk loci" prone to autoimmunity induction contribute (or not) to plant immunity. Furthermore, we are drawn towards the development of technologies and ressources in the plant biotechnology sector. We developed ample resources for genome editing (based on Agrobacterium-mediated transformation of the genome editing machinery) and for Golden Gate cloning-based hierarchical DNA assembly. One beneficial aspect of synthetic biology projects in a university setting is that these can nicely be addressed in BSc and/or MSc theses, where plant genetics timelines are not well suited.

Immune signaling pathways in Solanaceae

People: Johannes Stuttmann, Johannes Gantner, Jana Ordon

Plant pathogenic organisms commonly secrete so-called effector proteins into the cytoplasm of host cells to suppress host immune responses or manipulate other host processes to the benefit of the intruder. In resistant plant isolates, these effector proteins can become recognized by nucleotide-binding leucine-rich repeat (NLR) –type immune receptors. Effector recognition leads to immune receptor activation and initiation of the strong effector-triggered immunity (ETI) response. NLR-type receptors thus represent a central component of the plant immune system, but it yet remains unclear how activated NLRs function in ETI induction, which involves transcriptional regulation of thousands of genes. It is now commonly assumed that the NLR N-terminal domains – either a coiled coil (CC) domain in CNLs or a Toll-Interleukin1-receptor (TIR) domain in TNLs – function in signal initiation and transduction (reviewed in [1]). This is supported by dependence of immune responses mediated by TNLS, but not CNLs, on heterodimeric protein complexes based on the lipase-like protein EDS1 [2]. However, it should be noted that EDS1 might function redundantly with salicylic acid-based signaling mechanisms to mediate resistance responses downstream of CNLs also [3, 4]. Plant immune signaling has so far mainly been analyzed in Arabidopsis thaliana. We have now started to dissect immune signaling pathways in the solanaceous plant Nicotiana benthamiana (Nbenth), and use this system for functional analysis of tomato genes. The great benefit of working with Nbenth is its amenability to Agrobacterium-mediated transient protein expression. This allows the development of rapid gene functional assays, where variants of a gene of interest are expressed in a null mutant background. While this previously relied on experimentally variable virus-induced gene silencing (VIGS), genome editing now enables us to generate stable null mutants, at least in non-essential genes. We have reported on our first genome-edited Nbenth lines [5], and are constantly streamlining our procedures ever since. A first eds1 mutant line we generated allowed to identify the Xanthomonas effector XopQ as an inducer of EDS1-dependent immune responses in Nbenth [6]. We now use this mutant line to refine structure-function analyses of EDS1 heterodimeric complexes, with the aim to develop new working hypothesis for EDS1 functions by identifying functionally important features of heterocomplexes. These analyses are conducted in close contact with the lab of Prof. Jane Parker at the Max Planck Institute in Cologne, where similar aspects are being analyzed in the Arabidopsis system. We are also constantly generating novel genotypes through genome editing in Nbenth to expand from these analyses.

1. Maekawa T, Kufer TA, Schulze-Lefert P. Nat Immunol. 2011;12(9):817-26; 2. Wagner S, Stuttmann J, Rietz S, et al. Cell Host Microbe. 2013;14(6):619-30; 3. Cui H, Gobbato E, Kracher B, et al. New Phytol. 2016; 4. Venugopal SC, Jeong R-D, Mandal MK, et al. Plos Genetics. 2009;5(7) 5. Ordon J, Gantner J, Kemna J, et al. Plant J. 2017;89(1):155-68; 6. Adlung N, Prochaska H, Thieme S, et al. Front Plant Sci. 2016;7:1796;

(Auto-) Immunity mediated by RPP1-like genes in Arabidopsis

People: Johannes STuttmann, Jana Ordon

NLR-type immune receptors are generally activated upon recognition of foreign proteins, or their activity, within the host plant cytoplasm under infection conditions. Receptor activation induces a rapid and efficient immune response often accompanied by local cell death at infection sites, the "hypersensitive response" (HR). Local cell death is believed to restrict microbial infections and spread, but the severe consequences of receptor activation visually illustrate that NLR activity must underlie tight control. De-regulation of NLRs leads to autoimmunity, the induction of immune responses without an external trigger. Autoimmunity may differ in severity, but autoimmune lines are generally reduced in size and of low productivity. Autoimmunity can be induced by different scenarios, such as inactivation if a gene by mutation, overexpression of a gene or transgenesis, or combination of evolutionary distinct genomes in hybrids ("hybrid incompatibility", HI). In Arabidopsis intraspecific hybrid incompatibility, the "Dangerous Mix 2" locus encoding different TIR domain-containing NLRs has previously been identified as a major hotspot for hybrid incompatibility [1]. In Arabidopsis accession Landberg erecta (Ler), the DM2 locus conditions autoimmunity in interaction with three different alleles: SRF3 from accessions Kashmir and Kondara, an EMS-induced allele (old3-1) of O-acetylserine(thiol)lyase and a transgene encoding for a nuclear-localized version of the immune signaling component EDS1 (EDS1-YFPNLS) [2-4]. We analyze how these different proteins activate DM2-mediated resistance, and how DM2 genes may contribute to plant immunity.

1. Chae, E., et al., Species-wide genetic incompatibility analysis identifies immune genes as hot spots of deleterious epistasis. Cell, 2014. 159(6): p. 1341-51. 2. Alcazar, R., et al., Natural variation at Strubbelig Receptor Kinase 3 drives immune-triggered incompatibilities between Arabidopsis thaliana accessions. Nat Genet, 2010. 42(12): p. 1135-9. 3. Tahir, J., et al., Activation of R-mediated innate immunity and disease susceptibility is affected by mutations in a cytosolic O-acetylserine (thiol) lyase in Arabidopsis. Plant J, 2013. 73(1): p. 118-30. 4. Stuttmann, J., et al., Arabidopsis thaliana DM2h (R8) within the Landsberg RPP1-like Resistance Locus Underlies Three Different Cases of EDS1-Conditioned Autoimmunity. PLoS Genet, 2016. 12(4): p. e1005990.

Publications

• Peripheral infrastructure vectors and an extended set of plant parts for the modular cloning system. BioRxiv PrePrint, 2018, DOI: https://doi.org/10.1101/237768
• Further analysis of barley MORC1 using a highly efficient RNA-guided Cas9 gene editing system. Plant Biotechnology Journal, 2018, DOI: 10.1111/pbi.12924
• Dissection of TALE-dependent gene activation reveals that they induce transcription cooperatively and in both orientations. PLoS One, 2017, DOI: 10.1371/journal.pone.0173580
• Non-host Resistance Induced by the Xanthomonas Effector XopQ Is Widespread within the Genus Nicotiana and Functionally Depends on EDS1.FiPS, 2016, DOI: 10.3389/fpls.2016.01796
• Generation of chromosomal deletions in dicotyledonous plants employing a user-friendly genome editing toolkit. The Plant Journal, 2016 DOI: 10.1111/tpj.13319
• Arabidopsis thaliana DM2h (R8) within the Landsberg RPP1-like Resistance Locus Underlies Three Different Cases of EDS1-Conditioned Autoimmunity. PLoS Genetics, 2016, DOI: 10.1371/journal.pgen.1005990
• Structural Basis for Signaling by Exclusive EDS1 Heteromeric Complexes with SAG101 or PAD4 in Plant Innate Immunity. Cell Host Microbe, 2013, DOI: 10.1016/j.chom.2013.11.006
• Nucleocytoplasmic partitioning of tobacco N receptor is modulated by SGT1. New Phytologist, 2013, DOI: 10.1111/nph.12347
• Perturbation of Arabidopsis amino acid metabolism causes incompatibility with the adapted biotrophic pathogen Hyaloperonospora arabidopsidis. 2011, The Plant Cell, DOI: 10.1105/tpc.111.087684
• Novel aspects of COP9 signalosome functions revealed through analysis of hypomorphic csn mutants. Plant Signal Behav, 2009, PMID: 19847120
• COP9 signalosome- and 26S proteasome-dependent regulation of SCF-TIR1 accumulation in Arabidopsis. J Biol Chem, 2009, DOI: 10.1074/jbc.M809069200
• Staying in the fold: The SGT1/chaperone machinery in maintenance and evolution of leucine-rich repeat proteins. Plant Signal Behav, 2008, PMID: 19513219
• HpaA from Xanthomonas is a regulator of type III secretion. Mol Microbiol, 2008, DOI: 10.1111/j.1365-2958.2008.06280.x
• Interaction between SGT1 and cytosolic/nuclear HSC70 chaperones regulates Arabidopsis immune responses.The Plant Cell, 2007, DOI: 10.1105/tpc.107.051896
• Characterization of the nonconserved hpaB-hrpF region in the hrp pathogenicity island from Xanthomonas campestris pv. vesicatoria. Mol Plant Microbe Interact, 2007, DOI: 10.1094/MPMI-20-9-1063

Current and Past Lab Members

Current

• Johannes Gantner (PhD student)
• Carola Kretschmer (technician)
• Jana Ordon (Pre-Doc)
• Stefan Schünhoff (MSc thesis)
• Patrick Martin lab rotation (Forschungsgruppenpraktikum)
• Simon Ortmann (BSc thesis)

Past

• Konstantin Schmidt, BSc thesis
• Robert Hose, BSc thesis
• Patrick Martin, BSc thesis
• Jana Ordon, BSc thesis and MSc thesis
• Lennart Schwalgun, BSc thesis
• Mara Riechmann, lab rotation (Forschungsgruppenpraktikum)
• Jan Kemna, lab rotation (Forschungsgruppenpraktikum)
• Samuel Grimm, lab rotation (Forschungsgruppenpraktikum)
• Theresa Ilse, lab rotation (Forschungsgruppenpraktikum)
• Mauro Bressan, guest scientist from Verona
• Theresa Ilse (MSc thesis)

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