Prof. Dr. Gabriel Schaaf
Prof. Dr. Gabriel Schaaf Anschrift: Universität Bonn INRES - Institut für Nutzpflanzenwissenschaften und Ressourcenschutz Bereich Pflanzenernährung Karlrobert-Kreiten-Strasse 13 D-53115 Bonn Email: gabriel.schaaf ![]() Tel: (+49) 228 73-2851 Fax: (+49) 228 73-2489 | ||
Research Group: | ||
Education: | 2004: PhD (Dr. rer. nat.) in Biology/Molecular Plant Nutrition, University of Hohenheim (Stuttgart) 1998: Diploma in Biology, University of Tübingen 1998: “1. Staatsexamen” (teaching degree in Chemistry and Biology for High Schools), University of Tübingen 1993-1994: Exchange studies at the Institute of Marine Biology, Universidad Católica del Norte in Coquimbo (Chile) | |
Positions held: |
since 2017: Professor, Ecophysiology of Plant Nutrition, University of Bonn 2008-2017: Independent Research Group Leader, Center for Plant Molecular Biology, University of Tübingen (Emmy Noether Programme) 2005-2008: Post-doctoral Researcher at the Department for Cell & Developmental Biology, University of North Carolina at Chapel Hill (NC, USA) 2004: Post-doctoral Researcher at the Center for Plant Molecular Biology, University of Tübingen | |
Committee work & Mentoring | ||
Research focus: |
We are interested to better understand how plants perceive and react to nutrient imbalances, both deficiencies and toxicities. We particularly aim to understand how plants cope if such nutrient imbalances occur simultaneously with other stresses and how plants “decide” which of the often antagonistic pathways to trigger in order to cope with their various biotic and abiotic environmental challenges. We are especially intrigued by the enigmatic molecular messengers named inositol pyrophosphates, molecules that derive from phytate or InsP6 (an important ‘anti-nutrient’ for humans and non-ruminant animals but an important P-storage molecule for plants). Recent work in our lab focusses on the question of how plants use these messengers to coordinate phosphate starvation responses and to mount defenses against necrotrophic fungi and insect herbivores. Intriguingly, some phytopathogenic bacteria potently interfere in the synthesis of these messengers and we are curious to find out how and to which purpose this is done and how plants can become resistant against such bacteria. A second type of molecular messengers we are intrigued by are phosphoinositides (the lipid-arm of inositol signaling). These lipid messengers regulate a plethora of signaling events at membrane interfaces and thereby not only determine developmental processes but importantly also enable the translation of environmental cues into cellular responses. We have made substantial advances in characterizing SEC14-type lipid binding proteins that among others regulate the synthesis and distribution of phosphoinositides within cells. We are particular interested in the role of these proteins in membrane morphogenesis, root hair formation, nutrient acquisition and plant immunity. Our work covers different scales from high resolution crystallography at the nanometer scale to nutrient cycling at the field scale. To investigate the mechanisms by which plants perceive different abiotic and biotic signals and integrate diverse external stimuli into meaningful responses, we follow a interdisciplinary approach that combines ionomics, biochemistry, genetics, molecular-, and synthetic biology. Within the Cluster of Excellence “PhenoRob – Robotics and Phenotyping for Sustainable Crop Production” we are developing tools to diagnose nutrient imbalances by non-invasive methods and are interested in nutrient cycling in diversified cropping systems. We hope our work on both the molecular/genetic basis of nutrient homeostasis as well as our efforts in PhenoRob helps crop breeding and management efforts to reduce the negative footprint of agriculture. | |
Recent Talks (at public events): |
| May 27, 2021: Online discussion event on WBGU flagship report "New Technologies in Plant Breeding: Chances for Sustainable Agriculture" |
Selected publications: Web of Science google scholar
Siddiqui MN, Pandey K, Bhadhury SK, Sadeqi B, Schneider M, Sanchez-Garcia M, Stich B, Schaaf G, Léon J, Ballvora A (2023).
Convergently selected NPF2.12 coordinates root growth and nitrogen use efficiency in wheat and barley.
The New Phytologist, doi: https://doi.org/10.1111/nph.18820
Lopez G, Ahmadi SH, Amelung W, Athmann M, Ewert F, Gaiser T, Gocke MI, Kautz T, Postma J, Rachmilevitch S, Schaaf G, Schnepf A, Stoschus A, Watt M, Yu P, Seidel SJ (2023).
Nutrient deficiency effects on root architecture and root-to-shoot ratio in arable crops.
Front. Plant Sci., doi: https://doi.org/10.3389/fpls.2022.1067498
Chen X-R, Poudel L, Hong Z, Johnen P, Katti S, Tripathi A, Nile AH, Green SM, Khan D, Schaaf G, Bono F, Bankaitis VA, Igumenova TI (2023).
Mechanisms by which small molecules of diverse chemotypes arrest Sec14 lipid transfer activity.
J Biol Chem, doi: https://doi.org/10.1016/j.jbc.2022.102861
Liu G, Riemer E, Schneider R, Cabuzu D, Bonny O, Wagner CA, Qiu D, Saiardi A, Strauss A, Lahaye T, Schaaf G, Knoll T, Jessen JP, Jessen HJ (2023).
The phytase RipBL1 enables the assignment of a specific inositol phosphate isomer as a structural component of human kidney stones.
RSC Chem. Biol., doi: https://doi.org/10.1039/D2CB00235C
He X, Wang D, Jiang Y, Li M, Delgado-Baquerizo M, McLaughlin C, Marcon C, Guo L, Baer M, Moya YAT, von Wirén N, Deichmann M, Schaaf G, Piepho HP, Yang Z, Yang J, Yim B, Smalla K, Goormachtig S, de Vries FT, Hüging H, Sawers RJH, Reif JC, Hochholdinger F, Chen X, Yu P (2023).
Heritable maize microbiomes contribute to local adaptation and host stress resilience
bioRxiv, doi: https://doi.org/10.1101/2023.01.10.523403
Macabuhay A, Arsova B, Watt M, Nagel KA, Lenz H, Putz A, Adels S, Müller-Linow M, Kelm J, Johnson AAT, Walker R, Schaaf G, Roessner U (2022).
Plant Growth Promotion and Heat Stress Amelioration in Arabidopsis Inoculated with Paraburkholderia phytofirmans PsJN Rhizobacteria Quantified with the GrowScreen-Agar II Phenotyping Platform.
Plants 2022, 11(21), 2927; doi: https://doi.org/10.3390/plants11212927
Liu C, Mentzelopoulou A, Deli A, Papagavriil F, Ramachandran P, Perraki A, Claus L, Barg S, Dörmann P, Jaillais Y, Johnen P, Russinova E, Gizeli E, Schaaf G, Moschou PN (2022).
Phase Separation of a Nodulin Sec14-like protein Maintains Auxin Efflux Carrier Polarity at Arabidopsis Plasma Membranes.
bioRxiv, doi: https://doi.org/10.1101/2022.03.26.48593
Parvin Laha N, Giehl RFH, Riemer E, Qiu D, Pullagurla NJ, Schneider R, Walia Dhir Y, Yadav R, Mihiret YE, Gaugler P, Gaugler V, Mao H, Zheng N, von Wirén N, Adolfo Saiardi, Bhattacharjee S, Jessen HJ, Laha D, Schaaf G (2022).
INOSITOL (1,3,4) TRIPHOSPHATE 5/6 KINASE1-dependent inositol polyphosphates regulate auxin responses in Arabidopsis.
Plant Physiology, doi: https://doi.org/10.1093/plphys/kiac425
Riemer E, Pullagurla NJ, Yadav R, Rana P, Jessen HJ, Kamleitner M, Schaaf G, Laha D (2022).
Regulation of plant biotic interactions and abiotic stress responses by inositol polyphosphates.
Front. Plant Sci., doi: https://doi.org/10.3389/fpls.2022.944515
Gaugler P, Schneider R, Liu G, Qiu D, Weber J, Schmid J, Jork N, Häner M, Ritter K, Fernández Rebollo N, Giehl RFH, Trung MN, Yadav R, Fiedler D, Gaugler V, Jessen HJ, Schaaf G, Laha D (2022).
Arabidopsis PFA-DSP-type phosphohydrolases target specific inositol pyrophosphate messengers. bioRxiv: 2022.2003.2001.482514, doi: https://www.biorxiv.org/content/10.1101/2022.03.01.482514v1
Mau L, Junker S, Bochmann H, Mihiret YE, Kelm JM, Schrey SD, Roessner U, Schaaf G, Watt M, Kant J, Arsova B (2022).
Root Growth and Architecture of Wheat and Brachypodium Vary in Response to Algal Fertilizer in Soil and Solution.
Agronomy 2022, 12, 285, doi: https://doi.org/10.3390/agronomy12020285
Gulabani H, Goswami K, Walia Y, Roy A, Noor JJ, Ingole KD, Kasera M, Laha D, Giehl RFH, Schaaf G, Bhattacharjee S (2022).
Arabidopsis inositol polyphosphate kinases IPK1 and ITPK1 modulate crosstalk between SA-dependent immunity and phosphate-starvation responses.
Plant Cell Reports, 1-17. doi: 10.1007/s00299-021-02812-3
Haas TM, Mundinger S, Qiu D, Jork N, Ritter K, Dürr-Mayer T, Ripp A, Saiardi A, Schaaf G, Jessen HJ (2021).
Stable isotope phosphate labelling of diverse metabolites is enabled by a family of 18O‐phosphoramidites.
Angew Chem Int Ed Engl, doi: https://doi.org/10.1002/ange.202112457
Riemer E, Qiu D, Laha D, Harmel RK, Gaugler P, Gaugler V, Frei M, Hajirezaei MR, Laha NP, Krusenbaum L, Schneider R, Saiardi A, Fiedler D, Jessen HJ, Schaaf G, Giehl RFH (2021).
ITPK1 is an InsP6/ADP phosphotransferase that controls phosphate signaling in Arabidopsis.
Molecular Plant 14, 1864-1880.
Walia Y, Kasera M, Ingole KD, Peddiraju S, Roy A, Laha D, Schaaf G, Bhattacharjee S (2021).
Arabidopsis inositol polyphosphate kinases regulate COP9 signalosome deneddylase functions in phosphate-homeostasis.
bioRxiv, doi: https://doi.org/10.1101/2020.10.02.323584
Laha D, Kamleitner M, Johnen P, Schaaf G (2021).
Analyses of Inositol Phosphates and Phosphoinositides by Strong Anion Exchange (SAX)-HPLC.
Plant Lipids, 365-378.
Gulabani H, Goswami K, Walia Y, Noor JJ, Ingole KD, Roy A, Laha D, Schaaf G, Bhattacharjee S
(2021).
Arabidopsis inositol polyphosphate kinases IPK1 and ITPK1 modulate crosstalks between SA-dependent immunity and phosphate-starvation responses.
bioRxiv, doi: https://doi.org/10.1101/2021.01.27.428180
Yu P, He X, Baer M, Beirinckx S, Tian T, Moya YAT, Zhang Y, Deichmann M, Frey FP, Bresgen V, Li C, Razavi BS, Schaaf G, von Wirén N, Su Z, Bucher M, Tsuda K, Goormachtig S, Chen X, Hochholdinger F (2021).
Plant flavones enrich rhizosphere Oxalobacteraceae to improve maize performance under nitrogen deprivation.
Nature Plants 7, 481–499.
Seidel SJ, Gaiser T, Ahrends HE, Hüging H, Siebert S, Bauke SL, Gocke MI, Koch M, Schweitzer K, Schaaf G, Ewert F (2021).
Crop response to P fertilizer omission under a changing climate - Experimental and modeling results over 115 years of a long-term fertilizer experiment.
Field Crops Research 268, 108174.
Qiu D, Wilson MS, Eisenbeis VB, Harmel RK, Riemer E, Haas TM, Wittwer C, Jork N, Gu C, Shears SB, Schaaf G, Kammerer B, Fiedler D, Saiardi A, Jessen HJ (2020).
Analysis of inositol phosphate metabolism by capillary electrophoresis electrospray ionization mass spectrometry.
Nature Communications 11, 6035.
Yi J, Krusenbaum L, Unger P, Hüging H, Seidel S, Schaaf G, Gall J (2020).
Deep learning for non-invasive diagnosis of nutrient deficiencies in sugar beet using RGB images. Sensors 20(20), 5893; doi:10.3390/s20205893.
Gaugler P, Gaugler V, Kamleitner M, Schaaf G (2020).
Extraction and Quantification of Soluble, Radiolabeled Inositol Polyphosphates from Different Plant Species using SAX-HPLC.
J Vis Exp (160), e61495, doi:10.3791/61495.
Laha D, Parvin N, Hofer A, Giehl RFH, Fernandez-Rebollo N, von Wirén N, Saiardi A, Jessen HJ, Schaaf G (2019).
Arabidopsis ITPK1 and ITPK2 Have an Evolutionarily Conserved Phytic Acid Kinase Activity.
ACS Chem. Biol.; doi: 10.1021/acschembio.9b00423. [Epub ahead of print]
Zhu J, Lau K, Puschmann R, Harmel RK, Zhang Y, Pries V, Gaugler P, Broger L, Dutta AK, Jessen HJ, Schaaf G, Fernie AR, Hothorn LA, Fiedler D, Hothorn M (2019).
Two bifunctional inositol pyrophosphate kinases/phosphatases control plant phosphate homeostasis.
eLife;8:e43582 doi: 10.7554/eLife.43582
Pries V, Nöcker C, Khan D#, Johnen P, Hong Z, Tripathi A, Keller AL, Fitz M, Perruccio F, Filipuzzi I, Thavam S, Aust T, Riedl R, Ziegler S, Bono F, Schaaf G, Bankaitis VA, Waldmann H, Hoepfner D. (2018).
Target Identification and Mechanism of Action of Picolinamide and Benzamide Chemotypes with Antifungal Properties.
Cell Chemical Biology 25, 1–12 doi: 10.1016/j.chembiol.2017.12.007.
Zhang Q, van Wijk R, Shahbaz M, Roels W, van Schooten B, Vermeer J, Zarza X, Guardia A, Scuffi D, García-Mata C, Laha D, Williams P, Willems L, Ligterink W, Hoffmann-Benning S, Gillaspy G, Schaaf G, Haring M, Laxalt A, Munnik T (2017).
Arabidopsis Phospholipase C3 is Involved in Lateral Root Initiation and ABA Responses in Seed Germination and Stomatal Closure.
Plant and Cell Physiology, pcx194.
Blüher D, Laha D, Thieme S, Hofer A, Eschen-Lippold L, Masch A, Balcke G, Pavlovic I, Nagel O, Schonsky A, Hinkelmann R, Wörner J, Parvin N, Greiner R, Weber S, Tissier A, Schutkowski M, Lee J, Jessen H, Schaaf G, Bonas U* (2017).
A 1-phytase type III effector interferes with plant hormone signaling.
Nature communications 8, 2159.
de Campos MK, Schaaf G (2017).
The regulation of cell polarity by lipid transfer proteins of the SEC14 family.
Curr Opin Plant Biol 40, 158-168
Laha D, Parvin N, Dynowski M, Johnen P, Mao H, Bitters ST, Zheng N, Schaaf G (2016).
Inositol polyphosphate binding specificity of the jasmonate receptor complex.
Plant Physiol 171, 2364-70
Pavlovic I, Thakor DT, Bigler L, Wilson MSC, Laha D, Schaaf G, Saiardi A, Jessen HJ (2015).
Pro-Metabolites of 5-diphospho-myo-inositol pentakisphosphate.
Angew Chem Int Ed 54, 9622-6
Laha D, Johnen P, Azevedo C, Dynowski M, Weiß M, Capolicchio S, Mao H, Iven T, Steenbergen M, Freyer M, Gaugler P, de Campos MKF, Zheng N, Feussner I, Jessen HJ, Van Wees SC, Saiardi A, and Schaaf G (2015).
VIH2 Regulates the Synthesis of Inositol Pyrophosphate InsP8 and Jasmonate-Dependent Defenses in Arabidopsis.
Plant Cell 27, 1082-97
Ghosh R, de Campos MK, Huang J, Huh SK, Orlowski A, Yang Y, Tripathi A, Nile A, Lee HC, Dynowski M, Schäfer H, Róg T, Lete MG, Ahyayauch H, Alonso A, Vattulainen I, Igumenova TI, Schaaf G, Bankaitis VA (2015).
Sec14-Nodulin Proteins and the Patterning of Phosphoinositide Landmarks for Developmental Control of Membrane Morphogenesis.
Mol Biol Cell 26, 1764-81
Bankaitis VA, Ile KE, Nile AH, Ren J, Ghosh R, Schaaf G (2012)
Thoughts on Sec14-like nanoreactors and phosphoinositide signaling.
Adv Biol Regul 52, 115-21
Winklbauer EM, de Campos MKF, Dynowski D, and Schaaf G (2011).
A blueprint for functional engineering: Single point mutations reconstitute phosphatidylinositol presentation in a pseudo-Sec14 protein.
Commun Integr Biol 4, 674
Ren J, Schaaf G, Bankaitis VA, Ortlund EA, and Pathak MC (2011)
Crystallization and Preliminary X-ray Diffraction Analysis of Sfh3, a Member of the Sec14-protein Superfamily.
Acta Cryst F 67, 1239-1243
Schaaf G, Dynowski D, Mousley CJ, Shah SD, Yuan P, Winklbauer EM, Kaphan Freitas de Campos M, Trettin K, Quinones MC, Smirnova T, Yanagisawa LL, Ortlund EA, and Bankaitis VA* (2011)
Resurrection of a functional phosphatidylinositol transfer protein from a pseudo-Sec14 scaffold by directed evolution.
Mol Biol Cell 22, 892-905
Mousley CJ, Trettin KD, Tyeryar K, Ile KE, Schaaf G, Bankaitis VA (2010)
Sphingolipid metabolism in trans-Golgi/endosomal membranes and the regulation of intracellular homeostatic processes in eukaryotic cells.
Adv Enzyme Regul 50, 339-48
Bankaitis VA, Mousley CJ, Schaaf G (2010)
The Sec14 superfamily and mechanisms for cross-talk between lipid metabolism and lipid signaling.
Trends Biochem Sci 35, 150-60
Mousley CJ, Tyeryar KR, Ile KE, Schaaf G, Brost RL, Boone C, Guan X, Wenk MR, Bankaitis VA (2008)
Coordinate defects in Sec14 and Tlg2-dependent trans-Golgi and endosome dynamics derange ceramide homeostasis and compromise the unfolded protein response.
Mol Biol Cell 19, 4785-803
Dynowski M, Schaaf G, Loque D, Moran O, Ludewig U (2008)
Plant plasma membrane water channels conduct the signaling molecule H2O2.
Biochem J 414, 53-61
Schaaf G, Ortlund EA, Tyeryar KR, Mousley CJ, Ile KE, Garrett TA, Ren J, Woolls MJ, Raetz CRH, Redinbo MR, Bankaitis VA (2008)
Functional Anatomy of Phospholipid Binding and Regulation of Phosphoinositide Homeostasis by Proteins of the Sec14 Superfamily.
Mol Cell 29, 191-206
Smirnova TI, , Chadwick TG, Voinov MA, Poluektov O, van Tol J, Ozarowski A, Schaaf G, Ryan MM, and Bankaitis VA (2007).
Local Polarity and Hydrogen Bonding inside the Sec14p Phospholipid-binding Cavity: High-Field Multifrequency EPR Studies.
Biophysical J 92, 3686-95
Meda AR, Scheuermann E, Prechsl U, Erenoglu B, Schaaf G, Hayen H, Weber G, and von Wirén N (2007)
Iron Acquisition by Phytosiderophores Contributes to Cadmium Tolerance.
Plant Physiol 143, 1761-73
Smirnova TI, Chadwick TG, MacArthur R, Poluektov O, Song L, Ryan MM, Schaaf G, and Bankaitis VA (2006)
The chemistry of phospholipid binding by the Saccharomyces cerevisiae phosphatidylinositol transfer protein Sec14p as determined by EPR spectroscopy.
J Biol Chem 281, 34897-908
Schaaf G, Betts L, Garrett TA, Raetz CRH and Bankaitis VA (2006)
Crystallization and preliminary X-ray diffraction analysis of Sfh1p: A member of the Saccharomyces cerevisea Sec14p-like phosphatidylinositol transfer protein family.
Acta Cryst F 62, 1156-60
Ile KE, Schaaf G, and Bankaitis VA (2006)
Phosphatidylinositol transfer proteins and cellular nanoreactors for lipid signaling.
Nature Chem Biol 2, 576-583
Schaaf G, Honsbein A, Meda AR, Kirchner S, Wipf D and von Wirén N (2006)
AtIREG2 Encodes a Tonoplast Transport Protein Involved in Fe-Dependent Ni Detoxification in Arabidopsis thaliana Roots.
J Biol Chem 281, 25532-25540
Takano J, Wada M, Ludewig U, Schaaf G, von Wirén N, Fujiwara T (2006)
The Arabidopsis Major Intrinsic Protein NIP5;1 Is Essential for Efficient Boron Uptake and Plant Development under Boron Limitation.
Plant Cell 18, 1498 - 1509
Mayer M, Schaaf G, Mouro I, Lopez C, Colin Y, Neumann P, Cartron JP, Ludewig U (2006)
Different Transport Mechanisms in Plant and Human AMT/Rh-type Ammonium Transporters.
J Gen Physiol 127, 133-44
Phillips SE, Vincent P, Rizzieri KE, Schaaf G, Gaucher EA, Bankaitis VA (2006)
The diverse biological functions of phosphatidylinositol transfer proteins in eukaryotes.
Crit Rev Biochem Mol Biol 41, 21-49
Schaaf G, Schikora A, Häberle J, Vert G, Ludewig U, Briat JF, Curie C and von Wirén N (2005)
A putative function of the Arabidopsis Fe-phytosiderophore transporter homolog AtYSL2 in Fe and Zn homeostasis.
Plant Cell Physiol 46, 762-774
Römheld V and Schaaf G (2004)
Iron transport in plants: Future research in view of a plant nutritionist and a molecular biologist.
Soil Sci Plant Nutr 50, 1003 - 1012
Schaaf G, Erenoglu BE and von Wirén N (2004)
Physiological and biochemical characterization of metal-phytosiderophore transport in graminaceous species.
Soil Sci Plant Nutr 50, 955 - 964
Schaaf G, Ludewig U, Erenoglu BE, Mori S, Kitahara T, von Wirén N (2004)
ZmYS1 functions as a proton-coupled symporter for phytosiderophore- and nicotianamine-chelated metals.
J Biol Chem 279, 9091-9096
Schaaf G, Catoni E, Fitz M, Schwacke R, Schneider A, von Wirén N, Frommer WB (2002)
A putative role for the vacuolar calcium/manganese proton antiporter AtCAX2 in heavy metal detoxification.
Plant Biology 4, 612-618
Laufer G, Schaaf G, Bollgönn S, Günzl A (1999)
In vitro analysis of alpha-amanitin-resistant transcription from the rRNA, procyclic acidic repetitive protein, and variant surface glycoprotein gene promoters in Trypanosoma brucei.
Mol Cell Biol 19, 5466-5473
Dupré E, Schaaf G (1996)
Influence of ions on the unfolding of the spermatozoa of the rock shrimp, Rhynchocinetes typus.
J Exp Zool 274, 358-364
Books:
Schaaf G (2004)
Molecular and Biochemical Characterization of Plant Transporters Involved in the Cellular Homeostasis of Mn and Fe (Dissertation).
Der Andere Verlag, Osnabrück, Germany ISBN 3899592085