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Michael Udvardi

Posted by | March 13, 2021


Michael Udvardi

Job Title:


Work Address:

The Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA


Phone Number:

+1 580 224 6601


Google Scholar Profile


I earned my Ph.D. in plant biochemistry at the Australian National University (ANU) in 1989. I did postdoctoral research at Washington State University (1990-1992) in the USA and the Commonwealth Scientific and Industrial Research Organization in Australia (1992-1994), before taking faculty positions at the ANU (Lecturer, 1994-1998), the Max Planck Institute of Molecular Plant Physiology (Associate Professor, 1998-2006), and the Samuel Roberts Noble Foundation (Professor, 2006-present). I am primarily interested in how plants obtain nitrogen for growth, either as mineral nitrogen from the soil or from atmospheric di-nitrogen via symbiotic nitrogen fixation in bacteria. I have worked on symbiotic nitrogen fixation in model legumes, especially transport and metabolism in root nodules, using biochemical, molecular, genetic, and genomic methods. I was amongst the first to characterize ammonium and nitrate transporters in plants. Recently, my group has expanded work on plant nitrogen to include associative nitrogen fixation in grasses, and nitrogen recycling during shoot senescence in perennial plants. I am part of an international team that is trying to develop synthetic nitrogen-fixing symbioses in plants.

Research Areas:

  • Biological Nitrogen Fixation
  • Nitrogen Transport/Uptake
  • Nitrogen Metabolism
  • Nitrogen Signaling and Regulation
  • Nitrogen Use Efficiency
  • Nitrogen Recycling

Current N-related Projects:


Wuddineh, W.A., Mazarei, M., Zhang, J., Turner, G.B., Decker, S.R., Sykes, R.W., Davis, M.F., Udvardi, M.K., Stewart, N. (2016) Identification and overexpression of a Knotted1-like transcription factor in switchgrass (Panicum virgatum L.) for lignocellulosic feedstock improvement. Frontiers in Plant Science (in press).

Mus, F., Crook, M., Garcia, K., Garcia-Costas, A., Geddes, B., Kouri, E. D., Paramasivan, P., Ryu, M-H., Oldroyd, G., Poole, P., Udvardi, M., Voigt, C., Ané, J-M., Peters, J. (2016) Symbiotic Nitrogen Fixation and Challenges to Extending it to Non-Legumes. Applied and Environmental Microbiology (in press).

Kryvoruchko, I.S., Senjuti Sinharoy, S., Torres-Jerez, I., Sosso, D., Pislariu, C.I., Guan, D., Murray, J. , Benedito, V.A., Frommer, W.B., Udvardi, M.K. (2016) MtSWEET11, a Nodule-Specific Sucrose Transporter of Medicago truncatula. Plant Physiol. (in press).

Yang, J., Worley, E., Ma, Q., Li, J., Torres-Jerez, I., Li, G., Zhao, P.X. , Xu, Y. , Tang, Y., Udvardi, M. (2016) Nitrogen remobilization and conservation, and underlying senescence associated gene expression in perennial switchgrass, Panicum virgatum. New Phytologist (in press).

Senjuti Sinharoy, S., Liu, C., Breakspear, A., Guan, D., Shailes, S., Nakashima, J., Zhang, S., Wen, J., Torres-Jerez, I., Oldroyd, G., Murray, J.D., Udvardi, M. (2016) A Medicago truncatula Cystathionine Beta Synthase like domain-containing protein is required for rhizobial infection and symbiotic nitrogen fixation. Plant Physiol. (in press).

Kalloniati, C., Krompas, P., Karalias, G., Udvardi, M.K., Rennenberg, H., Herschbach, C., Flemetakis, E. (2015) Nitrogen-fixing nodules are a strong source of reduced sulfur that triggers global changes in sulfur metabolism in Lotus japonicus. The Plant Cell 27, 2384-400.

Patron, N.J. et al. (2015) Standards for plant synthetic biology: a common syntax for exchange of DNA parts. New Phytol. 208, 13-19.

Horváth, B., Domonkos, A., Kereszt, A., Szűcs, A., Ábrahám, E., Ayaydin, F., Bóka, K., Chen, Y., Chen, R., Murray, J., Udvardi, M., Kondorosi, E., Kaló, P. (2015) Loss of the nodule-specific cysteine rich peptide, NCR169 abolishes symbiotic nitrogen fixation in the Medicago truncatula dnf7 mutant. Proc. Natl. Acad. Sci. USA 112, 15232-7.

Sinharoy, S., Pislariu, C. I., Udvardi, M. K. (2015) A high-throughput RNA interference (RNAi)-based approach using hairy roots for the study of plant-rhizobia interactions. Methods Mol. Biol. 1287, 159-78.

Tejada-Jiménez, M., Castro-Rodríguez, R., Kryvoruchko, I., Mercedes Lucas, M., Udvardi, M., Imperial, J., González-Guerrero, M. (2015) Medicago truncatula Natural Resistance-Associated Macrophage Protein1 Is Required for Iron Uptake by Rhizobia-Infected Nodule Cells.  Plant Physiol. 168, 258-72.

Breuillin-Sessoms, F., Floss, D.S., Gomez, S.K., Pumplin, N., Ding, Y., Levesque-Tremblay, V., Noar, R.D., Daniels, D.A., Bravo, A., Eaglesham, J.B., Benedito, V.A., Udvardi, M.K., Harrison, M.J. (2015) Suppression of arbuscule degeneration in Medicago truncatula phosphate transporter 4 mutants is dependent on an ammonium transporter 2 family protein, MtAMT2;3. The Plant Cell 27, 1352-1366.

Yang, J., Worley, E., Torres-Jerez, I., Wang, M., Tang, Y., Udvardi, M. (2015) PvNAC1 and PvNAC2 are associated with leaf senescence and nitrogen use efficiency in switchgrass. BioEnergy Research 8, 868-880.

Tadege, M., Chen, F., Murray, J., Wen, J., Ratet, P., Udvardi, M.K., Dixon, R.A., Mysore, K.S. (2015) Control of vegetative to reproductive phase transition improves biomass yield and reduces lignin content in Medicago truncatula. BioEnergy Research 8, 857-867.

Yang, J., Worley, E., Udvardi, M. (2014) An AtNAP-AAO3 Regulatory Module Promotes Chlorophyll Degradation via ABA Biosynthesis in Arabidopsis Leaves. The Plant Cell 26, 4862-74.

Guefrachi, I., Nagymihaly, M., Pislariu, C.I., Van de Velde, W., Ratet, P., Mars, M., Udvardi, M.K., Kondorosi, E., Mergaert, Alunni, B. (2014) Extreme specificity of NCR gene expression in Medicago truncatula. BMC Genomics 15, 712.

Bahulikar, R. A., Torres-Jerez, I., Worley, E., Craven, K., Udvardi, M. K. (2014) Diversity of Nitrogen-Fixing Bacteria Associated with Switchgrass in the Native Tall-Grass Prairie of Northern Oklahoma. Appl. Environ. Microbiol. 80, 5636-5643.

Veerappan, V., Kadel, K., Alexis, N., Scott, A., Kryvoruchko, I., Sinharoy, S., Taylor, M., Udvardi, M., Dickstein, R. (2014) Keel petal incision: a simple and efficient method for genetic crossing in Medicago truncatula. Plant Methods 10, 11.

Gallego-Giraldo, L., Bhattarai, K., Pislariu, C., Nakashima, J., Jikumaru, Y., Kamiya, Y., Udvardi, M., Monteros, M., Dixon, R. (2014) Lignin modification leads to increase nodule numbers in alfalfa (Medicago sativa L.).  Plant Physiol. 164, 1139-50.

Cheng, X., Wang, M., Lee, H. K., Tadege, M., Ratet, P., Udvardi, M., Mysore, K. S., Wen, J. (2014) An efficient reverse genetics platform in the model legume Medicago truncatula.  New Phytol. 201, 1065-76.

Dai, X., Sinharoy, S., Udvardi, M., Zhao, P.X. (2013) PlantTFcat: an online plant transcription factor and transcriptional regulator categorization and analysis tool.  BMC Bioinformatics 14, 321.

Sinharoy, S., Torres-Jerez, I., Bandyopadhyay, K., Kereszt, A., Pislariu, C., Nakashima, J.,  Benedito, V.A.,  Kondorosi, E.,  and Udvardi, M.K. (2013). The C2H2 Transcription Factor REGULATOR OFSYMBIOSOME DIFFERENTIATION Represses Transcription of the Secretory Pathway Gene VAMP721a and Promotes Symbiosome Development in Medicago truncatula. Plant Cell 25: 3584-3601.

Wang, M., Verdier, J., Benedito, V.A., Tang, Y., Murray, J.D., Ge, Y., Becker, J.D., Carvalho, H., Rogers, C., Udvardi, M., He, J. (2013) LegumeGRN: A Gene Regulatory Network Prediction Server for Functional and Comparative Studies.  PLoS One 8(7): e67434.

Pérez-Delgado, C. M., Pérez-Delgado, C.M., García-Calderon, M., Sánchez, D.H., Udvardi, M.K., Kopka, J., Márquez, A.J., Betti, M. (2013) Transcriptomic and metabolic changes associated to photorespiratory ammonium accumulation in the model legume Lotus japonicus. Plant Physiol. 162: 1834-1848.

Guan, D., N. Stacey, Liu, C., Wen, J., Mysore, K., Torres-Jerez, I., Vernie, T., Tadege, M., Zhou, C., Wang, Z-Y., Udvardi, M.K., Oldroyd, G.E.D., Murray, J.D. (2013) Rhizobial infection is associated with the development of peripheral vasculature in nodules of Medicago truncatula. Plant Physiol. 162: 107-115.

Verdier, J., I. Torres-Jerez, Verdier, J., Wang, M., Andriankaja, A., Allen, S., He, J., Tang, Y., Murray, J.D., Udvardi, M.K. (2013) Establishment of the Lotus japonicus Gene Expression Atlas (LjGEA) and its use to explore legume seed development. Plant J. 74: 351-362.

Udvardi, M. K. and P. Poole (2013) Transport and metabolism in legume root nodules. Annual Review of Plant Biology 64: 781-805.

Zhang, J., Y. Lee, Torres-Jerez, I., Wang, M., Yin, Y., Chou, W., He, J., Shen, H., Srivastava, A.C., Pennacchio, C., Lindquist, E., Grimwood, J., Schmutz, J., Xu, Y., Sharma, M., Sharma, R., Bartley, L.E., Ronald, P.C., Saha, M.C., Dixon, R.A., Tang, Y., Udvardi, M.K. (2013) Development of an integrated transcript sequence database and a gene expression atlas for gene discovery and analysis in switchgrass (Panicum virgatum L.). Plant J. 74: 160-173.

Tsikou, D., C. Kalloniati, Kalloniati, C., Fotelli, M.N., Katinakis, P., Wang, T.L., Udvardi, M.K., Rennenberg, H., Flemetakis, E. (2013) Cessation of photosynthesis in Lotus japonicus leaves leads to reprogramming of primary and secondary metabolism in nodules. Journal of Experimental Botany 64: 1317-1332.

Bourcy, M., Brocard, L., Pislariu, C., Cosson, V., Mergaert, P., Mysore, K., Udvardi, M., Gourion, B., Ratet, P. (2013) Medicago truncatula DNF2 is a phosphatidylinositol-specific phospholipase C X domain containing protein required for bacteroid persistence and prevention of nodule senescence and plant defense reactions. New Phytologist 197: 1250-1261.

Xu, B., Sathitsuksanoh, N., Tang, Y., Udvardi, M.K., Zhang, J-Y., Shen, Z., Balota, M., Harich, K., Zhang, P. Y-H., Zhao, B. (2012) Overexpression of AtLOV1 in switchgrass alters plant architecture, lignin content, and flowering time.  PLoS One 7(12) e47399.

Balestrini, R., Ott, T., Güther, M., Bonfante, P., Udvardi, M.K., De Tullio, M.C. (2012) Ascorbate oxidase: The unexpected involvement of a ‘wasteful enzyme’ in the symbioses with nitrogen-fixing bacteria and arbuscular mycorrhizal fungi.  Plant Physiol. Biochem. 59: 71-79.

Pislariu, C.I., Murray, J., Wen, J., Cosson, V., Duvvuru Muni, R.R., Wang, M., Benedito, V., Andriankaja, A., Cheng, X., Torres-Jerez, I., Mondy, S., Zhang, S., Taylor, M., Tadege, M., Ratet, P., Mysore, K.S., Chen, R., Udvardi, M.K. (2012) A Medicago truncatula tobacco-retrotransposon (Tnt1)-insertion mutant collection with defects in nodule development and symbiotic nitrogen fixation. Plant Physiol. 159:1686-99.

Hakoyama, T., Niimi, K., Yamamoto, T., Isobe, S., Sato, S., Nakamura, Y., Tabata, S., Kumagai, H., Umehara, Y., Brossuleit, K., Petersen, T. R., Sandal, N., Stougaard, J., Udvardi, M.K., Tamaoki, M, Kawaguchi, M., Kouchi, H., Suganuma, N. (2012) The integral membrane protein SEN1 is required for symbiotic nitrogen fixation in Lotus japonicus nodules. Plant and Cell Physiology 53, 225-36.

Young, N. D. et. al. (2011) The Medicago genome provides insight into the evolution of rhizobial symbioses. Nature 480, 520-4.

Zhou, C., Han, L., Pislariu, C., Nakashima, J., Fu, C., Jiang, Q., Quan, L., Blancaflor, E., Bouton, J., Udvardi, M., Zhou, C., Wang, Z-Y. (2011) From model to crop: functional analysis of a STAY-GREEN gene in the model legume Medicago truncatula and effective use of the gene for alfalfa (M. sativa) improvement. Plant Physiol. 157: 1483-1496.

Han, Y., Kang, Y., Torres-Jerez, I., Cheung, F., Town, C.D., Zhao, P.X., Udvardi, M.K., Monteros, M.J. (2011) Genome-wide SNP discovery in tetraploid alfalfa using 454 sequencing and high-resolution melting analysis. BMC Genomics 12, 1-11.

Tsikou, D., Stedel, C., Kouri, E.D., Udvardi, M.K., Wang, T.L., Katinakis, P., Labrou, N.E., and Flemetakis, E.  (2011) Characterization of two novel nodule-enhanced α-type carbonic anhydrases from Lotus japonicus. Biochim. Biophys. Acta. 1814, 496-504.

Fotelli, M.N., Tsikou, D., Kolliopoulou, A., Aivalakis, G., Katinakis, P., Udvardi, M.K., Rennenberg, H., and Flemetakis, E. (2011) Nodulation enhances dark CO2 fixation and recycling in the model legume Lotus japonicus. J. Exp. Bot. 62, 2959-71.

Kalliampakou, K.I., Kouri, E.D., Boleti, H., Pavli, O., Maurousset, L., Udvardi, M.K., Katinakis, P., Lemoine, R., Flemetakis, E. (2011) Cloning and functional characterization of LjPLT4, a plasma membrane xylitol H+- symporter from Lotus japonicus.  Molecular Membrane Biology 28, 1-13.

Murray, J.D., Reddy Duvvuru Muni, R.S., Torres-Jerez, I., Tang, Y., Allen, S., Andriankaja, M., Li, G., Laxmi, A., Cheng, X., Vaughan, D., Schultze, M., Sun, J., Charpentier, M., Oldroyd, G., Tadege, M., Ratet, P., Mysore, K.S., Chen, R. and Udvardi, M.K. (2011) Vapyrin, a gene essential for intracellular progression of arbuscular mycorrhizal symbiosis, is also essential for infection by rhizobia in the nodule symbiosis of Medicago truncatula. Plant Journal 65, 244-52.

Becana, M., Matamoros, M., Udvardi, M. and Dalton, D.A. (2010) Recent insights into antioxidant defenses of legume root nodules. New Phytologist 188, 960-976.

Díaz, P., Betti, M., Sánchez, D.H., Udvardi, M.K., Monza, J. and Márquez, A.J. (2010) Deficiency in plastidic glutamine synthetase alters proline metabolism and transcriptomic response in Lotus japonicus under drought stress. New Phytologist 188, 1001-1013.

Goodrich-Blair, H., Ané, J.-M., Bever, J.D., Bordenstein, S., Bright, M., Chaston, J.M., Clay, K., Currie, C.R., Douglas, A.E., Gerardo, N., Harrison, M.J., Ley, R.E., McFall-Ngai, M., Mukherjee, A., Rader, B., Raffa, K.F., Ruby, E.G., Saffo, M.B., Selosse, M.-A., Sonnenburg, J.L., Stock, S.P., Suen, G., Turnau, K., Udvardi, M., Visick, K.L. and Weis, V.M. (2010) Symbiosis research, technology, and education: Proceedings of the 6th International Symbiosis Society Congress held in Madison Wisconsin, USA, August 2009. Symbiosis 51, 1-12.

Wang, M., Benedito, V. A., Zhao, P. X., Udvardi, M. K. (2010) Inferring large-scale gene regulatory networks using a low-order constraint-based algorithm.  Molecular BioSystems 6, 988-98.

Benedito, V.A., Li, H., Dai, X., Wandrey, M., Kaundal, R., Torres-Jerez, I., Harrison, M.J., Tang, Y., Zhao, P.X. and Udvardi, M.K. (2010) Genomic inventory and transcriptional analysis of Medicago truncatula membrane transporters. Plant Physiol. 152, 1716-30.

Lefebvre, B., Timmers, T., Mbengue, M., Moreau, S., Hervé, C., Toth, K., Bittencourt-Silvestre, J., Klaus, D., Deslandes, L., Godiard, L., Murray, J., Udvardi, M. K., Raffaele, S., Mongrand, S., Cullimore, J., Gamas, P., Niebel, A., Ott, T. (2010) A remorin protein interacts with symbiotic receptors and regulates bacterial infection. Proc. Natl. Acad. Sci. U S A 107, 2343-2348.

Li, H., Benedito, V., Dai, X., Udvardi, M., Zhao, P. X. (2009) TransportTP: A two-phase classification approach for membrane transporter prediction and characterization. BMC Bioinformatics 10, 418.

He, J., Benedito, V. A., Wang, M., Murray, J. D., Zhao, P. X., Tang, Y, Udvardi, M. K. (2009) The Medicago truncatula gene expression atlas web server.  BMC Bioinformatics 10, 441.

Yang, J., Worley, E., Wang, M., Lahner, B., Salt, D.E., Saha, M. and Udvardi, M.K. (2009) Natural variation for nutrient-use and remobilization efficiencies in switchgrass. BioEnergy Research 2, 257–266.

Libault, M., Joshi, J., Benedito, V.A., Xu, D., Udvardi, M.K. and Stacey, G. (2009) Legume transcription factor genes; what makes legumes so special? Plant Physiol. 151, 991-1001.

Hernández, G., Valdés-López, O., Ramírez, M., Goffard, N., Weiller, G., Aparicio-Fabre, R., Fuentes, S. I., Erban, A., Kopka, J., Udvardi, M.K., Vance, C.P. (2009) Global changes in the transcript and metabolic profiles during symbiotic nitrogen fixation in phosphorus-stressed common bean plants.  Plant Physiol. 151, 1221-38.

Hogslund, N., Radutoiu, S., Krusell, L., Voroshilova, V., Hannah, M. A., Goffard, N., Sanchez, D. H., Lippold, F., Ott, T., Sato, S., Tabata, S., Liboriussen, P., Lohmann, G. V., Schauser, L., Weiller, G. F., Udvardi, M. K., Stougaard, J. (2009) Dissection of symbiosis and organ development by integrated transcriptome analysis of Lotus japonicus mutant and wild-type plants. PLoS One 4, e6556.

Kouri, E.D., Kaliampakou,  A. I., Stedel C., Udvardi, M. K., Katinakis, P., Labrou, N. E., and Flemetakis, E. (2009)  Molecular and Biochemical characterization of the Purvulin-type PPIases in Lotus japonicus.  Plant Physiol. 150, 1160-73.

Andreadeli, A., Flemetakis, E., Axarli, I., Dimou, M., Udvardi, M.K., Katinakis, P., Labrou, N.E. (2009) Cloning and characterization of Lotus japonicus formate dehydrogenase: A possible correlation with hypoxia.  Biochim Biophys Acta 1794, 976-984.

Ott, T., Sullivan, J., James, E. K., Flemetakis, E., Günther, C., Gibon, Y., Ronson, C., and Udvardi, M. (2009) Absence of symbiotic leghemoglobins alters bacteroid and plant cell differentiation during development of Lotus japonicus root nodules.  Molec. Plant Microbe Interact. 22, 800-808.

Young, N.D. and Udvardi, M.K. (2009) Translating Medicago truncatula genomics to crop legumes. Curr. Opinion. Plant Biol. 12, 193-201.

Rogato, A., D’Apuzzo, E., Barbulova, A., Omrane, S., Stedel, C., Simon-Rosin, U., Katinakis, P., Flemetakis, M., Udvardi, M., and Chiurazzi, M.  (2008) Tissue-specific down-regulation of LjAMT1;1 compromises nodule function and enhances nodulation in Lotus japonicus. Plant Molecular Biology  68, 585-95.

Udvardi, M.K., Czechowski, T., and Scheible, W.-R. (2008) Eleven Golden Rules of Quantitative RT-PCR.  Plant Cell 20, 1736-7.

Kakar, K., Wandrey, M., Czechowski, T., Gaertner, T., Scheible, W-R., Stitt, M., Torres-Jerez, I., Xiao, Y., Redman, J., Wu, H., Cheung, F., Town, C., and Udvardi, M. (2008)  A community resource for high-throughput quantitative RT-PCR analysis of transcription factor gene expression in Medicago truncatula.  Plant Methods 4, 18.

Benedito, V. A., Torres-Jerez, I., Murray, J. D., Andriankaja, A., Allen, S., Kakar, K., Wandrey, M., Verdier, J., Zuber, H., Ott, T., Moreau, S., Niebel, A., Frickey, T.,Weiller, G., He, J., Dai, X., Zhao, P. X., Tang, Y., Udvard, M. K. (2008) A gene expression atlas of the model legume Medicago truncatula.  Plant J. 55, 504-13.

Efrose, R. C., Flemetakis, E., Sfichi, L., Stedel, C., Kouri, E. D., Udvardi, M. K., Kotzabasis, K., Katinakis, P.  (2008) Characterization of spermidine and spermine synthases in Lotus japonicus: induction and spatial organization of polyamine biosynthesis in nitrogen fixing nodules.  Planta 228, 37-49.

Ruffel, S., Freixes, S., Balzergue, S., Tillard, P., Jeudy, C., Martin-Magniette, M. L., van der Merwe, M. J., Kakar, K., Gouzy, J., Fernie, A. R., Udvardi, M., Salon, C., Gojon, A., Lepetit, M. (2008) Systemic signaling of the plant N status triggers specific transcriptome responses depending on the N source in Medicago truncatula. Plant Physiology 146, 2020-35.

Frickey, T., Benedito, V., Udvardi, M., and Weiller, G. (2008) AffyTrees: facilitating comparative analysis of Affymetrix plant microarray chips.  Plant Physiol. 146, 377-386.

D’Antuono, A.L., Ott, T., Krusell, L., Voroshilova, V., Ugalde, R.A., Udvardi, M., and Lepek, V.C. (2008)  Defects in rhizobial cyclic glucan and lipopolysaccharide synthesis alter legume gene expression during nodule development. Mol. Plant Microbe Interact. 21, 50-60.

Günther, C., Schlereth, A., Udvardi, M., and Ott, T. (2007) Metabolism of reactive oxygen species is attenuated in leghemoglobin-deficient nodules of Lotus japonicus. Mol Plant Microbe Interact. 20, 1596-1603.

Udvardi, M. K., Kakar, K., Wandrey, M., Montanari, O., Murray, J. , Andriankaja, A., Zhang, J. -Y., Benedito, V., Hofer, J. M. I., Chueng, F., Town, C. D. (2007) Legume Transcription Factors: Global Regulators of Plant Development and Response to the Environment. Plant Physiol. 144, 538-549.

Benedito, V.A., Dai, X.B., He, J., Zhao, P.X., Udvardi, M.K. (2006) Functional genomics of plant transporters in legume nodules.  Functional Plant Biology 33, 731-736.

Flemetakis, E., Efrose, R.C., Ott, T., Stedel, C., Aivalakis, G., Udvardi, M.K., Katinakis, P.  (2006) Spatial and Temporal Organization of Sucrose Metabolism in Lotus japonicus Nitrogen-Fixing Nodules Suggests a Role for the Elusive Alkaline/Neutral Invertase. Plant Mol Biol. 62, 53-69.

Wood, C.C., Poree, F., Dreyer, I., Koehler, G.J., Udvardi, M.K.. (2006) Mechanisms of ammonium transport, accumulation, and retention in ooyctes and yeast cells expressing Arabidopsis AtAMT1;1.  FEBS Lett. 580, 3931-3936.

Hoque, M.S., Masle, J., Udvardi, M.K., Ryan, P.R., and Upadhyaya, N.M. (2006) Over-expression of the rice OsAMT1-1 gene increases ammonium uptake and content, but impairs growth and development of plants under high ammonium nutrition.  Functional Plant Biology 33, 153-163.

Czechowski, T., Altmann, T., Stitt, M., Udvardi, M.K., and Scheible W-R. (2005) Genome-Wide Identification and Validation of Novel and Superior Normalizer Genes in Arabidopsis thaliana. Plant Physiol. 139, 5-17.

Udvardi, M.K. and Scheible, W-R. (2005) GRAS genes and the symbiotic Green Revolution.  Science 308, 1749-50.

Udvardi, M.K., Parniske, M., Tabata, S., and Stougaard, J. (2005) Lotus japonicus: Legume research in the fast lane.  TIPS 10, 222-228.

Krusell, L., Krause, K., Ott, T., Desbrosses, G., Kramer, U., Sato, S., Nakamura, Y., Tabata, S., James, E.K., Sandal, N., Stougaard, J., Kawaguchi, M., Miyamoto, A., Suganuma, N., Udvardi, M.K.  (2005) The sulfate transporter SST1 is crucial for symbiotic nitrogen fixation in Lotus japonicus root nodules. Plant Cell 17, 1625-36.

Ott, T., van Dongen, J.T., Guther, C., Krusell, L., Desbrosses, G., Vigeolas, H., Bock, V., Czechowski, T., Geigenberger, P., Udvardi, M.K.  (2005) Symbiotic leghemoglobins are crucial for nitrogen fixation in legume root nodules but not for general plant growth and development. Current Biology 15, 531-5.

Desbrosses, G.G., Kopka, J., Udvardi, M.K. (2005) Lotus japonicus metabolic profiling: Development of GC-MS resources for the study of plant-microbe interactions.  Plant Physiol. 137, 1302-18.

Oldroyd, G.E., Harrison, M.J, and Udvardi, M. (2005) Peace talks and trade deals: keys to long-term harmony in legume-microbe symbioses.  Plant Physiol. 137, 1205-10.

Flemetakis, E., Efrose, R.C., Desbrosses, G., Dimou, M., Delis, C., Aivalakis, G., Udvardi, M.K., and Katinakis, P. (2004) Induction and spatial organization of polyamine biosynthesis during nodule development in Lotus japonicus. Molec. Plant-Microbe Interact. 17, 1283-1293.

Scheible, W-R., Morcuende, R., Czechowski, T., Osuna, D., Fritz, C., Palacios-Rojas, N., Thimm, O., Udvardi, M.K., Stitt, M. (2004) Genome-wide Reprogramming of Primary and Secondary Metabolism, Protein Synthesis, Cellular Growth Processes and the Regulatory Infrastructure of Arabidopsis in Response to Nitrogen. Plant Physiol. 136, 2483-2499.

Gaude, N., Tippmann, H., Flemetakis, E., Katinakis, P., Udvardi, M., and Dörmann, P. (2004) The Galactolipid Digalactosyldiacylglycerol Accumulates in the Peribacteroid Membrane of Nitrogen-Fixing Nodules of Soybean and Lotus. J. Biol. Chem. 279, 34624-30.

Colebatch, G., Desbrosses, G., Ott, T., Krusell, L., Montanari, O., Kloska, S., Kopka, J., and Udvardi, M.K. (2004) Global changes in transcription orchestrate metabolic differentiation during symbiotic nitrogen fixation in Lotus japonicus Plant J. 39, 487-512.

Desbrosses, G., Kopka, C., and Udvardi, M.K. (2004) Lotus japonicus LjKUP encodes a potassium transporter of the plasma membrane and is induced significantly during nodule organogenesis. MPMI 7, 789-97.

Czechowski, T., Bari, R.P., Stitt, M., Scheible W-R., and Udvardi, M.K. (2004) Real-time RT-PCR profiling of over 1,400 Arabidopsis transcription factors: unprecedented sensitivity reveals novel root- and shoot-specific genes. Plant J. 38, 366-379.

D’Apuzzo, E., Rogato, A., Simon-Rosin, U., El Alaoui, H., Barbulova, A., Betti, M., Dimou, M., Katinakis, P., Marquez, A., Marini, A., Udvardi, M. K., and Chiurazzi, M (2004) Characterisation of three functional high affinity ammonium transporters in Lotus japonicus with differential transcriptional regulation and spatial expression. Plant Physiol. 134, 1763-74.

Wandrey, M., Trevaskis, B., Brewin, N. and Udvardi, M.K. (2004) Molecular and cell biology of a family of VDAC porins in Lotus japonicus. Plant Physiol. 13, 182-93.

Flemetakis, E., Dimou, M., Cotzur, D., Aivalakis, G., Efrose, R.C., Kenoutis, C., Udvardi, M., Katinakis, P. (2003) A Lotus japonicus beta-type carbonic anhydrase gene expression pattern suggests distinct physiological roles during nodule development. Biochim. Biophys. Acta.1628, 186-94.

Flemetakis, E., Dimou, M., Cotzur, D., Efrose, R.C., Aivalakis, G., Colebatch, G., Udvardi, M., Katinakis, P.  (2003) A sucrose transporter, LjSUT4, is up-regulated during Lotus japonicus nodule development. J Exp Bot. 54, 789-91.

Simon-Rosin, U., Wood, C., and Udvardi, M.K. (2003) Molecular and cellular characterisation of LjAMT2;1, an ammonium transporter from the model legume Lotus japonicus.  Plant Mol. Biol. 51, 99-108.

Sohlenkamp, C., Wood, C.C., Roeb, G.W., and Udvardi, M.K. (2002) Characterisation of Arabidopsis AtAMT2: a high-affinity ammonium transporter of the plasma membrane. Plant Physiol. 130, 1788-1796.

Udvardi, M.K. (2002) Legume genome and EST sequencing catalyse discoveries in symbiosis research.  Genome Biology 3, 4028.1-4028.3.

Trevaskis, B., Wandrey, M., Colebatch, G. and Udvardi, M.K. (2002) The soybean GmN6L gene encodes a late nodulin expressed in the infected zone of nitrogen-fixing nodules. MPMI 15, 630-636.

Trevaskis, B, Colebatch, C., Desbrosses, G., Wandrey, M., Wienkoop, S., Saalbach, G., and Udvardi, M. (2002) Differentiation of plant cells during symbiotic nitrogen fixation.  Comp. Funct. Genom. 3, 151-157.

Colebatch, G., Kloska, S., Trevaskis, B., Freund, S., Altmann, T., Udvardi, M. (2002) Novel aspects of symbiotic nitrogen fixation uncovered by transcript profiling with cDNA arrays. MPMI 15, 411-420.

Colebatch, G., Trevaskis, B., and Udvardi, M. (2002) Symbiotic nitrogen fixation research in the post-genomics era. New Phytol. 153, 36-41.

Colebatch, G., Trevaskis, B., and Udvardi, M. (2002) Functional Genomics: tools of the trade. New Phytol. 153, 27-36.

Moreau, S., Thomson, R.M., Kaiser, B.N., Trevaskis, B., Guerinot, M.L., Udvardi, M.K., Puppo, A., and Day, D.A. (2002) GmZIP1 encodes a symbiosis-specific zinc transporter in soybean.  J. Biol. Chem. 277, 4738-46.

Day, D.A., Kaiser, B.N., Thomson, R., Udvardi, M.K., Moreau, S., and Puppo, A. (2001). Nutrient transport across membranes from legume nodules. Aust. J. Plant Physiol. 28, 667-674.

Shelden, M.C., Dong, B., De Bruxelles, G., Trevaskis, B., Whelan, J., Ryan, P.R., Howitt, S.M., and Udvardi, M.K. 2001. Arabidopsis ammonium transporters, AtAMT1;1 and AtAMT1;2, have different biochemical properties and functional roles. Plant and Soil 231, 151-160.

Udvardi, M.K. 2001. Model legumes strut their stuff. MPMI 14, 6-9.

Sohlenkamp, C., Shelden, M., Howitt, S., and Udvardi, M.K. (2000) Characterisation of Arabidopsis AtAMT2: a novel ammonium transporter in plants.  FEBS Letters 467, 273-278.

Panter, S., Thomson, R., de Bruxelles, G., Laver, D., Trevaskis, B., and Udvardi, M.K. (2000) Identification with proteomics of novel proteins associated with the peribacteroid membrane of soybean root nodules. MPMI 13, 325-333.

Howitt, S.M. and Udvardi, M.K. (2000) Structure, function, and regulation of ammonium transporters in plants. BBA Biomembranes 1465, 152-170.

Federova, E., Thompson, R., Whitehead, L.F., Udvardi, M.K., and Day, D.A. (1999) Location of H+-ATPases in soybean root nodules. Planta. 209, 25-32.

Amarasinghe, B.H.R.R., deBruxelles, G., Braddon, M., Onyeocha, I., Forde, B.G., and Udvardi, M.K. (1998) Regulation of GmNRT2 expression and nitrate transport activity in roots of soybean (Glycine max). Planta. 206, 44-52.

Kaiser, B.N., Finnegan, P.M., Tyerman, S.D., Whitehead, L.F., Bergersen, F.J., Day, D.A., and Udvardi, M.K. (1998) Characterisation of an ammonium transport protein from the peribacteroid membrane of soybean nodules. Science. 281, 1202- 1206.

Kahn, M.L., McDermott, T.R., and Udvardi, M.K. (1998) Carbon and nitrogen metabolism in the Rhizobiaceae. In The Rhizobiaceae. HP Spaink, A Kondorosi, and PJJ Hooykaas, Eds. Kluwer Academic Publishers, Dordrecht.

Udvardi, M.K. and Day, D.A. (1997) Metabolite transport across symbiotic membranes of legume nodules.  Annu. Rev. Plant Physiol. Plant Mol. Biol. 48, 493-523.

Wittenberg, J.B., Wittenberg, B.A., Day, D.A., Udvardi, M.K. and Appleby, C.A. (1996)  Siderophore-bound iron in the peribacteroid space of soybean root nodules.  Plant and Soil 178, 161-169.

Udvardi, M.K. and Kahn, M.L.  (1993)  Evolution of the Rhizobium-legume symbiosis: why do bacteroids fix nitrogen? Symbiosis 14, 87-101.

Udvardi, M.K., McDermott, T.R. and Kahn, M.L.  (1993)  Isolation and analysis of a cDNA clone that encodes isocitrate dehydrogenase in soybean (Glycine max L.).  Plant Mol. Biol. 21, 739-752.

Day, D.A. and Udvardi, M.K.  (1993)  Metabolite exchange across symbiosome membranes. Symbiosis 14, 175-189.

Udvardi, M.K., Lister, D.L. and Day, D.A.  (1992)  Isolation and characterization of an ntrC mutant of Bradyrhizobium (Parasponia) sp. ANU289.  J. Gen. Microbiol. 138, 1019-1025.

Udvardi, M.K. and Kahn, M.L.  (1991)  Isolation and analysis of a cDNA clone that encodes an alfalfa (Medicago sativa) aspartate amino transferase.  Mol.Gen.Genet. 231, 97-105.

Udvardi, M.K., Lister, D.L. and Day, D.A.  (1991)  ATPase activity and anion transport across the peribacteroid membrane of isolated soybean symbiosomes.  Arch. Microbiol. 156, 362-366.

Udvardi, M.K. and Day, D.A.  (1990)  Ammonia (14C-methylamine) transport across the bacteroid and peribacteroid membranes of soybean root nodules.  Plant Physiol.  94, 71-76.

Ou Yang, L., Udvardi, M.K. and Day, D.A.  (1990)  Specificity and regulation of the dicarboxylate carrier on the peribacteroid membrane of soybean nodules.  Planta 182, 437-444.

Udvardi, M.K., Ou Yang, L., Young, S and Day, D.A.  (1990)  Sugar and amino acid transport across symbiotic membranes from soybean nodules.  Molecular Plant-Microbe Interactions 3, 334-340.

Udvardi, M.K. and Day, D.A.  (1989)  Electrogenic ATPase activity on the peribacteroid membrane of soybean (Glycine max L.) root nodules.  Plant Physiol.  90, 982-987.

Day, D.A., Price, G.D. and Udvardi, M.K.  (1989) The membrane interface of the Bradyrhizobium japonicum – Glycine max symbiosis: peribacteroid units from soybean nodules.  Aust. J. Plant Physiol. 16, 69-84.

Udvardi, M.K., Salom, C.L. and Day, D.A.  (1988)  Transport of L-glutamate across the bacteroid membrane but not the peribacteroid membrane from soybean root nodules.  Molecular Plant-Microbe Interactions 1, 250-254.

Udvardi, M.K., Price, G.D., Gresshoff, P.M. and Day, D.A.  (1988)  A dicarboxylate transporter on the peribacteroid membrane of soybean nodules.  FEBS Lett.  231, 36-40.

Howitt, S.M., Udvardi, M.K., Day, D.A. and Gresshoff, P.M.  (1986)  Ammonia transport in free-living and symbiotic Rhizobium sp. ANU289.  J. Gen. Microbiol.  132, 257-261.

Udvardi, M.K., Day, D.A. and Gresshoff, P.M.  (1986)  Stimulation of respiration and nitrogenase in bacteroids of siratro (Macroptilium atropurpureum) by plant nodule cytosol.  Plant Cell Reports 3, 207-209.