Kiwamu Tanaka

Kiwamu Tanaka

Associate Professor Plant Sciences Building Johnson Hall 354/358/370 (lab)

Research lab

Research Specialty and Interests

Plants are continuously exposed to various stresses caused by changes in the environment and attacks by other organisms, i.e., abiotic and biotic stresses. Therefore, plants require sophisticated surveillance systems to detect potentially life-threatening events by recognizing danger signals.  

Indeed, plants have evolved a large number of receptor kinases, most of which are likely involved in the response to different stresses. These receptors recognize not only exogenous, enemy-derived molecules but also endogenous molecules from own damaged cells and tissues as danger signals, referred to as damage-associated molecular patterns (DAMPs). Plants use DAMPs for damaged-self recognition to evoke immune responses and damage healing. 

Words in the form of a tree.

Extracellular ATP is one of the DAMP signals in both animals and plants. Although ATP is well-known as the energy currency molecule in the living cell, once ATP is released into the extracellular space following cellular damage, it acts as a DAMP signal. Our research focuses on the function of this DAMP signal for in-depth understanding of plant defense mechanisms against pathogen and insect attacks. Based on our research, we would further like to determine how we can improve plant growth and vigor and therefore increase crop yields.

We also focus on a project to implement integrated control strategies for potato powdery scab disease, which has in recent decades insidiously spread in many regions where potatoes are grown, including most potato production areas in Washington State. Typical symptoms are cosmetic damage on the skin of potato tubers and the formation of root galls, which reduce nutrient and water uptake. Moreover, the powdery scab pathogen vectors a virus, Potato mop-top virus (PMTV) which causes plant growth suppression and internal tuber necrosis. Most importantly, PMTV is an impediment to foreign trade.  

The objectives of this project are to develop a diagnostic method to survey powdery scab infestation on farms, and to isolate and apply novel plant defense inducers (i.e., PAMPs or DAMPs) derived from infected potato roots. This work is important because current management of the disease relies heavily on fungicides and soil fumigations that are only partially effective against powdery scab, and are expensive and risky to applicators and the environment. 


  • 2005 Ph.D. United Graduate School of Agricultural Sciences, Kagoshima University, Japan 
  • 2002 M.S. Graduate School of Agriculture, Kagoshima University, Japan 
  • 2000 B.S. Department of Agriculture, Kagoshima University, Japan 

Professional Experience and Activities


  • 2020-Present   Associate Professor, Department of Plant Pathology, Washington State University 
  • 2014-20   Assistant professor, Department of Plant Pathology, Washington State University 
  • 2011-14   Research Scientist, Division of Plant Sciences, University of Missouri 
  • 2006-11   Post-doctoral fellow, Division of Plant Sciences, University of Missouri 

Awards, Honors, and Memberships

  • 2019 WSU Office of Research Pacesetter Award 
  • 2018 WSU Provost Featured Faculty Member Recognition 
  • 2012 Elected Full Fellow of Sigma Xi 
  • American Association for the Advancement of Science (AAAS) 
  • American Phytopathological Society (APS) 
  • American Society of Plant Biologists (ASPB) 
  • International Society for Molecular Plant-Microbe Interactions (IS-MPMI) 
  • Potato Association of America (PAA) 


(Full Publication List on My Bibliography or Google Scholar) 

  • Wei W, Xu L, Peng H, Zhu W, Tanaka K, Cheng J, Sanguinet KA, Vandemark G, Chen W (2022) A novel fungal extracellular effector inactivates plant polygalacturonase-inhibiting protein. Nat. Commun. 13: 2213. doi:10.1038/s41467-022-29788-2 
  • Mora-Romero GA, Félix-Gastélum R, Bomberger RA, Romero-Urías C, Tanaka K (2022) Common potato disease symptoms: ambiguity of symptom-based identification of causal pathogens and value of on-site molecular diagnostics. J. Gen. Plant Pathol. 88 (2): 89-104. doi:10.1007/s10327-021-01045-2  
  • Marcec MJ, Tanaka K (2022) Crosstalk between calcium and ROS signaling during flg22-triggered immune response in Arabidopsis leaves. Plants 11 (1): 14. doi:10.3390/plants11010014 
  • Tanaka K, Heil M (2021) Damage-associated molecular patterns (DAMPs) in plant innate immunity: applying the danger model and evolutionary perspectives. Annu. Rev. Phytopathol. 59 doi:10.1146/annurev-phyto-082718-100146 
  • Kumar S, Tripathi D, Okubara PA, and Tanaka K (2020) Purinoceptor P2K1/DORN1 enhances plant resistance against a soilborne fungal pathogen, Rhizoctonia solani. Front. Plant Sci. 11: 572920. doi:10.3389/fpls.2020.572920 
  • Moroz N, Tanaka K (2020) FlgII-28 is a major flagellin-derived defense elicitor for potato. Mol. Plant-Microbe Int. 33: 247-255. doi:10.1094/MPMI-06-19-0164-R 
  • DeShields JB, Moroz N, Braley LE, Mora-Romero GA, Tanaka K (2019) Recombinase polymerase amplification (RPA) for the rapid isothermal detection of Spongospora subterranea f. sp. subterranea and potato mop-top virus. Am. J. Potato Res. 96: 617-624. doi:10.1007/s12230-019-09750-7 
  • Jewell, JB, Tanaka K (2019) Transcriptomic perspective on extracellular ATP signaling: a few curious trifles. Plant Signal. Behav. 14: e1659079. doi:10.1080/15592324.2019.1659079
  • Marcec MJ, Gilroy S, Poovaiah BW, Tanaka K (2019) Mutual interplay of Ca2+ and ROS signaling in plant immune response. Plant Sci. 283: 343-354. doi:10.1016/j.plantsci.2019.03.004 
  • Ramachandran SR, Kumar S, Tanaka K (2019) Quantification of extracellular ATP in plant suspension cell cultures (Chapter 5). In Plant innate immunity (W. Gassmann, ed.). Methods Mol. Biol. Humana, New York. Vol. 1991, pp.43-54. doi:10.1007/978-1-4939-9458-8_5 
  • Jewell JB, Sowders JM, He R, Willis MA, Gang DR, Tanaka K (2019) Extracellular ATP shapes a defense-related transcriptome both independently and along with other defense signaling pathways. Plant Physiol. 179: 1144-1158. doi:10.1104/pp.18.01301 
  • DeShields JB, Bomberger RA, Woodhall JW, Wheeler DL, Moroz N, Johnson DA, Tanaka K (2018) On-site molecular detection of soil-borne phytopathogens using a portable real-time PCR system. J. Vis. Exp. e56891. doi:10.3791/56891 
  • Tripathi D, Tanaka K (2018) A crosstalk between extracellular ATP and JA signaling pathways. Plant Signal. Behav. 13: e1432229. doi:10.1080/15592324.2018.1432229 
  • Tripathi D, Zhang T, Koo AJ, Stacey G, Tanaka K (2018) Extracellular ATP acts on jasmonate signaling to reinforce plant defense. Plant Physiol. 176: 511-23. doi:10.1104/pp.17.01477 
  • Moroz N, Huffaker A, Tanaka K (2017) Extracellular alkalinization assay for detection of early defense response. Curr. Protoc. Plant Biol. 2: 210-20. doi:10.1002/cppb.20057 
  • Moroz N, Fritch KR, Marcec MJ, Tripathi D, Smertenko A, Tanaka K (2017) Extracellular alkalinization as a defense response in potato cells. Front. Plant Sci. 8: 32. doi:10.3389/fpls.2017.00032