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John McDowell

John McDowell
550 Latham Hall
Blacksburg VA 24061


I serve as the J.B. Stroobants Professor of Biotechnology, with an 70% research, 30% teaching appointment.  My research program focuses on molecular and genomic aspects of plant-pathogen interactions, with emphasis on oomycetes. I teach two graduate-level courses that illustrate fundamental and translational aspects of plant biology.


  • Plant-pathogen interactions


  • Ph.D. Genetics, Univ. of Georgia, 1995
  • B.A. Cell and Molecular Biology, Univ. of Tennessee, 1987

Pathogens have evolved sophisticated molecular weapons to exploit plants as sources of food and shelter. For example, many pathogens have evolved the capacity to export their own proteins to the interior of plant cells. Once they have gained entry to the interior of plant cells, these pathogen "effector" proteins manipulate specific plant regulatory proteins to make the plant more susceptible to infection. Plants, in turn, have evolved large collections of surveillance proteins that recognize specific pathogen molecules (including some effector proteins) as signals of invasion. This molecular recognition can trigger potent immune responses in the plant, including programmed plant cell suicide at the site of invasion.

My group investigates the molecular interplay and co-evolution between pathogens effector proteins, their targets inside plant cells, and the plant immune surveillance system. Most of our effort is focused on the interaction between the model plants Arabidopsis thaliana and Nicotiana benthamiana, and various oomycete pathogens including Hyaloperonospora arabidopsidis (downy mildew disease) and species from the Phytophthora genus. We use molecular genetic and genome-enabled approaches to address the following, interrelated questions:

  1. How do pathogens suppress host immune responses? We are focusing on so-called "RXLR" effector proteins in H. arabidopsidis. We are currently characterizing the function of some of these genes, including their localization inside plant cells and the plant proteins that are targeted by these effectors. These projects will provide insight into the molecular mechanisms through which oomycete pathogens cause disease and may reveal novel plant pathways that play a role in interaction with microbes.
  2. How do pathogens extract nutrients from their host? We are collaborating with several researchers to identify plant nutrient transporters that are co-opted by pathogens to supply carbon, nitrogen, and sulphur. This project will provide a clearer understanding of how pathogens utilize plants as nutritional resources and may open the door to new strategies for engineering resistance in plants.
  3. Can fundamental research on plant-pathogen interactions be translated into new strategies for disease control? Diseases caused by plant pathogens are a perennial threat to global food security, causing 100's of billions of dollars in damage on an annual basis. In the past, we have used effector-based screens to identify new sources of resistance against soybean root/stem rot caused by Phytophthora sojae. Now, we are searching for plant genes that pathogens exploit (“disease susceptibility genes”) to identify candidates that could be edited to function as resistance genes.
  • GRAD 5134: Translational Plant Science: This course considers the processes and pitfalls between a good idea in the lab and development of products with real-world value.
  • PPWS 5454: Plant Disease Physiology and Development: This team-taught course explores how plants and pathogens interact at a molecular level.

I contribute to secondary education and public engagement, by participating in the Partnership for Research and Education in Plants program at Virginia Tech. This program brings together biology teachers and research scientists to guide high school students in investigating gene function in Arabidopsis.

Professor | 2018 – present 
School of Plant and Environmental Sciences
Virginia Polytechnic Institute and State University 

Professor | 2013-2018
Department of Plant Pathology, Physiology, and Weed Science
Virginia Polytechnic Institute and State University 

Associate Professor | 2006 – 2013
Department of Plant Pathology, Physiology, and Weed Science
Virginia Polytechnic Institute and State University

Interim Head | 2010
Department of Plant Pathology, Physiology, and Weed Science 
Virginia Polytechnic Institute and State University

Assistant Professor | 2000-2006
Department of Plant Pathology, Physiology, and Weed Science
Virginia Polytechnic Institute and State University

Postdoctoral Fellow | 1995-1999
University of North Carolina-Jeff Dangl lab, Chapel Hill, N.C.

Associate Scientific Director | 2013-2021
Fralin Life Science Institute
Virginia Polytechnic Institute and State University

Principal Scientist, | 2011 – Present
Latham Hall
Virginia Polytechnic Institute and State University

Rotating Program Director | 2021 – 2022 
Integrative Organismal Systems, Biological Sciences
National Science Foundation

Editorial Board | 2021-present

Editor-in-Chief | 2022-present
Annual Review of Phytopathology

Editorial Board | 2019-2021
Annual Review of Phytopathology

Editorial Board | 2018-Present
Science Advances

Editor-in-Chief | 2016-2018
Molecular Plant-Microbe Interactions

Editorial Board | 2012-2016

PLOS Genetics

Review Editor | 2011-2021
Frontiers in Plant-Microbe Interactions

Senior Editor | 2010-2015
Molecular Plant-Microbe Interactions

Editorial Board | 2008-2018
Molecular Biotechnology

Advisory Board | 2004-2008
The Plant Journal

Editorial Board | 2000-2005
Molecular Plant Pathology

Associate Editor | 2000-2005
Molecular Plant-Microbe Interactions

  • Academy for Faculty Service, Virginia Tech, 2016
  • Certificate of Teaching Excellence, College of Agriculture and Life Sciences, Virginia Tech, 2016
  • Henderson Award, "Outstanding Performance as a Faculty Member", Dept. of Plant Pathology, Physiology, and Weed Science, Virginia Tech, 2007

(since 2010)

  1. Bilir, Ö., Göl, D., Hong, Y., J McDowell, J.M., Tör, M. Small RNA-based plant protection against diseases, Frontiers in Plant Science, Accepted 7/28/22.
  2. Wang, W., Liu, J., Mishra, B., Mukhtar, S., McDowell, J.M., Sparking a sulfur war between plants and pathogens. Trends in Plant Science, Accepted 7/21/22, Image selected for the December issue’s cover
  3. Wilson, R.A., McDowell, J.M., 2022, Recent advances in understanding of fungal and oomycete effectors, Current Opinion in Plant Biology, Curr Opin Plant Biol.:68:102228. Image selected for the August issue’s cover.
  4. Dinkeloo K., Pelly Z., McDowell J.M.*, Pilot G.*. 2022 A split green fluorescent protein system to enhance spatial and temporal sensitivity of translating ribosome affinity purification [published online ahead of print, 2022 Apr 18]. Plant J.;10.1111/tpj.15779. doi:10.1111/tpj.15779 *co-Corresponding Authors
  5. Besnard J., Sonawala U., Maharjan B., Collakova E., Finlayson S.A., Pilot G., McDowell J.M. Okumoto S., 2020. Increased expression of UMAMIT amino acid transporters results in activation of salicylic acid dependent stress response. Frontiers in Plant Science 11:2214
  6. Herlihy J.H., Long T.A.*, McDowell JM*, 2020 Iron homeostasis and plant immune responses: recent insights and translational implications. Journal of Biological Chemistry 295:13444-13457. *co-Corresponding Authors
  7. Lai Y., Lu X.M,. Daron J., Pan S., Wang J., Wang W., Tsuchiya T., Holub E., McDowell J.M., Slotkin R.K., Le Roch, K.G., Eulgem, T., 2020. The Arabidopsis PHD-finger protein EDM2 has multiple roles in balancing NLR immune receptor gene expression. PLoS Genetics 16:e1008993
  8. Telli O., Jimenez‐Quiros C., McDowell J.M,. Tör M., 2020. Effect of light and dark on the growth and development of downy mildew pathogen Hyaloperonospora arabidopsidis. Plant Pathology 69:1291-1300.
  9. Anderson, R., Deb, D., Withers, J., He, S.Y. and McDowell, J.M., 2019. An oomycete RXLR effector triggers antagonistic plant hormone crosstalk to suppress host immunity. bioRxiv.
  10. Cui, C., Herlihy, J., Bombarely, A., McDowell, J.M. and Haak, D.C., 2019. Draft assembly of Phytophthora capsici from long-read sequencing uncovers complexity. Molecular Plant-Microbe Interactions, 32:1559-1563.
  11. Herlihy, J., Ludwig, N.R., van den Ackerveken, G. and McDowell, J.M., 2019. Oomycetes used in Arabidopsis research. The Arabidopsis Book, 17:1-26.
  12. Ha, S., Dimitrova, E., Hoops, S., Altarawy, D., Ansariola, M., Deb, D., Glazebrook, J., Hillmer, R., Shahin, H., Katagiri, F., McDowell, J.M., Megraw, M., Setubal, J., Tyler, B. M. & Laubenbacher, R. 2019. PlantSimLab - a modeling and simulation web tool for plant biologists. BMC Bioinformatics, 20:508.
  13. Lai, Y., Cuzick, A., Lu, X.M., Wang, J., Katiyar, N., Tsuchiya, T., Le Roch, K., McDowell, J.M., Holub, E. and Eulgem, T., 2019. The Arabidopsis RRM domain protein EDM 3 mediates race‐specific disease resistance by controlling H3K9me2‐dependent alternative polyadenylation of RPP7 immune receptor transcripts. The Plant Journal, 97:646-60.
  14. McDowell, J.M., 2019. Focus on Activation, Regulation, and Evolution of MTI and ETI. Molecular Plant-Microbe Interactions, 32:5.
  15. Sonawala, U., Dinkeloo, K., Danna, C.H., McDowell, J.M. and Pilot, G., 2018. Functional linkages between amino acid transporters and plant responses to pathogens. Plant Science, 277:79-88.
  16. Deb, D., Mackey, D., Opiyo, S., and McDowell, J. M., 2018, Application of alignment-free bioinformatics methods to identify an oomycete protein with structural and functional similarity to the bacterial AvrE effector protein. PLOS One, 13:e0195559.
  17. Deb, D., Anderson, R. G., Kim, T., Tyler, B., and McDowell, J. M., 2018, Conserved RxLR effectors from oomycetes Hyaloperonospora arabidopsidis and Phytophthora sojae suppress PAMP- and effector-triggered immunity in diverse plants, Molecular Plant-Microbe Interactions, 31:374-385.
  18. Dalio, R.J.D., Herlihy, J., Oliveira, T.S., McDowell, J.M., Machado, M., 2018 Effector biology in focus: a primer for computational prediction and functional characterization Molecular Plant-Microbe Interactions, 31:34-45.
  19. Wang, Y., Ma, W., and McDowell, J.M., 2018 Focus on Effector-Triggered Susceptibility, Molecular Plant-Microbe Interactions, 31:5.
  20. Michelmore, R., G. Coaker, R. Bart, G. Beattie, A. Bent, T. Bruce, D. Cameron, J. Dangl, S. Dinesh-Kumar, R. Edwards, S. Eves-van den Akker, W. Gassmann, J. T. Greenberg, L. Hanley-Bowdoin, R. J. Harrison, J. Harvey, P. He, A. Huffaker, S. Hulbert, R. Innes, J. D. G. Jones, I. Kaloshian, S. Kamoun, F. Katagiri, J. Leach, W. Ma, J.M. McDowell, J. Medford, B. Meyers, R. Nelson, R. Oliver, Y. Qi, D. Saunders, M. Shaw, C. Smart, P. Subudhi, L. Torrance, B. Tyler, B. Valent and J. Walsh 2017. Foundational and Translational Research Opportunities to Improve Plant Health. Molecular Plant Microbe Interactions, 30:515-516.
  21. Kong, P., McDowell, J. M., & Hong, C. (2017). Zoospore Exudates from Phytophthora nicotianae Affect Salicylic Acid Independent Defense in Arabidopsis. PLOS One, 12:e0180523
  22. Anderson, R. G., Deb, D., Fedkenheuer, K., and McDowell, J. M., 2015, "Recent Progress in RXLR Effector Research", Molecular Plant-Microbe Interactions, 28:1063-1072.
  23. Anderson, R. G. and McDowell, J. M. (2015), A PCR assay for the quantification of growth of the oomycete pathogen Hyaloperonospora arabidopsidis in Arabidopsis thaliana. Molecular Plant Pathology. DOI: 10.1111/mpp.12247
  24. Kamoun S., O. Furzer, J. Jones, H. Judelson, G. Ali, R. Dalio, S. Roy, L. Schena, A. Zambounis, F. Panabières, D. Cahill, M. Ruocco, A. Figueiredo, X. Chen, J. Hulvey, R. Stam, K. Lamour, M. Gijzen, B. Tyler, N. Gruenwald, S. Mukhtar, D. Tomé, M. Tör, G. van den Ackerveken, J. M. McDowell, F. Daayf, W. Fry, H. Lindqvist-Kreuze, H. Meijer, B. Petre, J., Ristaino, K. Yoshida, P. Birch, F. Govers. (2015) The Top 10 oomycete pathogens in molecular plant pathology, Molecular Plant Pathology, DOI: 10.1111/mpp.12190.
  25. McDowell, J. M. (2014) Hyaloperonospora arabidopsidis: A model pathogen of Arabidopsis. In Genomics of Plant-Associated Fungi and Oomycetes: Dicot Pathogens (pp. 209-234). Springer Berlin Heidelberg.
  26. McDowell J.M., Carr J, Lorito M. (2014) Focus on translational research. Molecular Plant-Microbe Interactions. 27:195.
  27. Stegmann, M., Anderson, R. G., Westphal, L., Rosahl, S., McDowell, J. M., & Trujillo, M. (2014) The exocyst subunit Exo70B1 is involved in the immune response of Arabidopsis thaliana to different pathogens and cell death. Plant Signaling & Behavior, 8, e27421.
  28. McDowell, J.M. and Meyers, B.C., 2013, A transposable element is domesticated for service in the plant immune system, Proc. Natl. Acad. Sci. USA, 110:14821-14822
  29. Zhang, C., Xie, Q., Anderson, R.G., Ng, G., Seitz, N.C., Peterson, T., McClung, C.R., McDowell, J.M., Kong, D., Kwak, J., and Lu, H., 2013. Crosstalk between the Circadian Clock and Innate Immunity in Arabidopsis, PLOS Pathogens, 9:e1003370.
  30. McDowell, J.M. 2013. Genomic and transcriptomic insights into lifestyle transitions of a hemi-biotrophic fungal pathogen, New Phytologist, 197:1032-1034
  31. Stegmann, M., Anderson, R.G., Ichimura, K., Pecenkova, T., Reuter, P., Zarsky, V., McDowell, J.M., Shirasu, K., and Trujillo, M., 2012. The Ubiquitin Ligase PUB22 Targets a Subunit of the Exocyst Complex Required for PAMP-Triggered Responses in Arabidopsis. The Plant Cell, 24:4703-4716.
  32. Anderson R.G., Casady, M., Fee, R., Deb, D., Vaughan, M., Fedkenheuer, K., Huffaker, A., Smeltz, E., Tyler B., McDowell, J.M., 2012. Suppression of defense responses in distantly related plants by homologous RXLR effectors from Hyaloperonospora arabidopsidis and Phytophthora sojae, The Plant Journal, 72:882-893.
  33. McDowell, J.M., 2011, Beleaguered Immunity. Science, 334:1354.
  34. McDowell, J.M., 2011, Genomes of plant rust pathogens reveal adaptations for obligate parasitism, Proc. Natl. Acad. Sci. USA, 108:8921-2.
  35. McDowell J.M., Hoff, T., Anderson, R., Deegan, D., 2011, Propogation, Storage, and Assays with Hyaloperonospora arabidopsidis, a model oomycete pathogen of Arabidopsis, Methods in Molecular Biology, 712:137-51.
  36. McDowell J.M., 2011, Examples of How New Experimental Technologies Have Enabled Landmark Advances in Understanding of Plant Immunity Over the Last Half-Century, Methods in Molecular Biology, 712:v-x.
  37. Plant Immunity: Methods and Protocols, 2011, Methods in Molecular Biology, Volume 712, (J. McDowell, ed.), Springer Science, New York.
  38. Baxter L, Tripathy S, Ishaque N, Boot N, Cabral A, Kemen E, Thines M, Ah-Fong A, Anderson R, Badejoko W, Bittner-Eddy P, Boore JL, Chibucos MC, Coates M, Dehal P, Delehaunty K, Dong S, Downton P, Dumas B, Fabro G, Fronick C, Fuerstenberg SI, Fulton L, Gaulin E, Govers F, Hughes L, Humphray S, Jiang RH, Judelson H, Kamoun S, Kyung K, Meijer H, Minx P, Morris P, Nelson J, Phuntumart V, Qutob D, Rehmany A, Rougon-Cardoso A, Ryden P, Torto-Alalibo T, Studholme D, Wang Y, Win J, Wood J, Clifton SW, Rogers J, Van den Ackerveken G, Jones JD, McDowell JM*, Beynon J, Tyler BM, 2010, Signatures of adaptation to obligate biotrophy in the Hyaloperonospora arabidopsidis genome. Science, 330:1549-51 (*Corresponding author)
  39. Mohr, T. J., Mammarella, N. T., Hoff, T., Woffenden, B. W., Jelesko, J. G., and McDowell, J. M., 2010, The Arabidopsis downy mildew resistance gene RPP8 is induced by pathogens and salicylic acid, and is regulated by W box cis elements. Molecular Plant-Microbe Interactions, 23:1303-15.