Laboratories and faculty

Plant Immunity

Prof. Saijo
SAIJO Yusuke
Assistant Professor
Labs HP

Outline of Research and Education

In nature, plants cope with a wide range of microbes, which reside on the surface of or within plant tissues, under fluctuating environments. Plants accommodate and often exploit plant-inhabiting microbes in adapting to adverse conditions, despite an elaborate immune system to detect and repel microbes. We hypothesize that plants distinguish pathogens from non-pathogens in a context-dependent manner, by sensing “danger” signals generated upon pathogen attack in addition to microbial structures. We aim to decipher the molecular mechanisms by which plants integrate microbial and abiotic cues to fine-tune their associations with microbes and facilitate their adaptation to different habitats. Our major focuses involve immune receptor signaling and its modulation by abiotic stress sensing and signaling, defense-related transcriptional reprogramming, and infection strategies of pathogenic and endophytic microbes. Our studies are expected to reveal significant insight into the molecular basis for plant-microbe-environment associations, and thus offer new effective approaches to controlling plant health and growth in sustainable agriculture.

Major Research Topics

  1. Danger sensing and signaling in plant-microbe interactions
  2. Signal integration between biotic and abiotic stress responses
  3. Endophytic and pathogenic microbes in plants
  4. Plant-associated microbiomes
  5. Transcriptional reprogramming and priming in plant immunity
Fig. 1
Fig. 1 Layered structure of microbe- and damage-signal receptor signaling provides an important basis for robust pathogen resistance and its fine-tuning.
Fig. 2
Fig. 2 Transcriptional reprogramming and priming in plant immunity. Following the initial defense activation (left arrow) upon recognition of pathogen-associated patterns (PTI) or effectors (ETI), defense-related genes become primed to allow faster and/or greater responses upon second stimulation (right arrow). Histone modifications provide a basis for this immune memory that is sustained in the generation and can be inherited by the next generation.
Fig. 3
Fig. 3 Root colonization of endophyte Colletotrichum tofieldiae (Ct). Confocal microscope images of Ct constitutively expressing cytoplasmic GFP (green, labeled by dotted lines) and A. thaliana expressing VAMP722-mRFP (Red). Intracellular hyphae inside a root cortical cell are enveloped by PIP2A-mCherry-labeled host membranes (arrows). 8 day post inoculation. Bar = 10 μm.


  1. Saijo and Loo, New Phytologist in press 2019
  2. Shinya et al., Plant J., 94, 4, 626-637, 2018
  3. Saijo et al., Plant J., 93, 592-613, 2018
  4. Hiruma et al., Curr. Opin. Plant Biol., 44, 145-154, 2018
  5. Ariga et al., Nature Plants, 3, 17072, 2017
  6. Yasuda, Okada and Saijo, Curr. Opin. Plant Biol., 38, 10-18, 2017
  7. Yamada et al., Science, 354,1427-1430, 2016
  8. Espinas et al., Front. Plant Sci., 7, 1201, 2016
  9. Hiruma et al., Cell, 165, 464-474, 2016
  10. Yamada et al, EMBO J., 35, 46-61, 2016
  11. Ross et al., EMBO J., 33, 62-75, 2014
  12. Tintor et al., Proc Natl Acad Sci U.S.A., 110, 6211-6216, 2013
  13. Serrano et al., Plant Physiol., 158, 408-422, 2012
  14. Lu et al., Proc Natl Acad Sci USA, 106, 22522-22527, 2009
  15. Saijo et al., EMBO J., 28, 3439-3449, 2009
  16. Saijo et al., Molecular Cell, 31, 607-613, 2008
  17. Shen et al., Science, 315, 1098-1103, 2007