The innate immune system is the first line of inducible defense against infectious disease. A key function of innate immunity is the detection of pathogen-associated molecular patterns (PAMPs) produced by infectious agents but not host cells and the launch of appropriate defense responses. Recent discoveries have revealed remarkable conservation in the recognition of PAMPs by leucine-rich-repeat (LRR) receptors and in signaling mechanisms of innate immune responses in plants, insects, worms, and mammals. We propose to use integrative molecular, cellular, biochemical, genomic, and genetic approaches to elucidate the signal transduction pathways induced by a well-defined bacterial flagellin peptide elicitor flg22 in the model plant Arabidopsis thaliana. The Research proposal will focus on the investigation of a MAPKKK (MEKK1) and a small GTPase (ROP11), that interact with the flg22 receptor kinase (FLS2) and mediate MAPK-dependent and MAPK-independent pathways, respectively, and converge on WRKY22/29 transcription factors in flg22 signaling. Protoplast transient assays and transgenic and mutant plants will be used for the studies.
Four specific aims are: 1) Investigate the molecular mechanisms that link a specific MAPK cascade to the flg22 receptor FLS2 (a LRR receptor kinase) 2) Elucidate the function and mechanisms of ROP11-FLS2 interaction in flg22 signaling 3) Define the direct target genes of WRKY22/29 transcription factors in flg22 signaling 4) Determine the roles of the flg22 MAPK cascade, ROP11, and WRKY22/29 in plant defense responses against bacterial and fungal pathogens using transgenic and mutant plants. It has been well documented that flagellin peptide flg22 and many other pathogen-derived elicitors induce conserved signaling responses such as protein kinase activation, calcium influx, oxidative signaling, and transcriptional reprogramming. The proposed studies on the flg22 MAPK cascade, ROP11, and WRKY22/29 transcription factors that act downstream of FLS2 receptor kinase in early flg22 signaling will enhance our understanding of the molecular mechanisms underlying the early events of innate immune responses and improve our ability to manipulate durable disease resistance in plants.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
1R01GM070567-01A1
Application #
6868539
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Marino, Pamela
Project Start
2005-03-12
Project End
2009-02-28
Budget Start
2005-03-12
Budget End
2006-02-28
Support Year
1
Fiscal Year
2005
Total Cost
$354,375
Indirect Cost
Name
Massachusetts General Hospital
Department
Type
DUNS #
073130411
City
Boston
State
MA
Country
United States
Zip Code
02199
Shi, Lin; Wu, Yue; Sheen, Jen (2018) TOR signaling in plants: conservation and innovation. Development 145:
Kim, Hyeon-Ji; Wu, Chung-Yi; Yu, Hui-Ming et al. (2017) Dual CLAVATA3 Peptides in Arabidopsis Shoot Stem Cell Signaling. J Plant Biol 60:506-512
Li, Zhenxiang; Zhang, Dandan; Xiong, Xiangyu et al. (2017) A potent Cas9-derived gene activator for plant and mammalian cells. Nat Plants 3:930-936
Chung, Hoo Sun; Sheen, Jen (2017) MAPK Assays in Arabidopsis MAMP-PRR Signal Transduction. Methods Mol Biol 1578:155-166
Liu, Kun-Hsiang; Niu, Yajie; Konishi, Mineko et al. (2017) Discovery of nitrate-CPK-NLP signalling in central nutrient-growth networks. Nature 545:311-316
Li, Lei; Sheen, Jen (2016) Dynamic and diverse sugar signaling. Curr Opin Plant Biol 33:116-125
Cheng, Zhenyu; Li, Jian-Feng; Niu, Yajie et al. (2015) Pathogen-secreted proteases activate a novel plant immune pathway. Nature 521:213-6
Li, Jian-Feng; Zhang, Dandan; Sheen, Jen (2015) Targeted plant genome editing via the CRISPR/Cas9 technology. Methods Mol Biol 1284:239-55
Xiong, Yan; Sheen, Jen (2015) Novel links in the plant TOR kinase signaling network. Curr Opin Plant Biol 28:83-91
Hamel, Louis-Philippe; Sheen, Jen; Séguin, Armand (2014) Ancient signals: comparative genomics of green plant CDPKs. Trends Plant Sci 19:79-89

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