Plants and animals rely on innate immunity to prevent potential infections by detection of pathogen-associated molecular patterns (PAMPs) through pattern recognition receptors (PRRs). In plants, PAMPs are perceived by cell-surface PRRs and mount PAMP- triggered immunity (PTI). Successful pathogens are able to suppress PTI by producing virulence effectors, which, in turn, are recognized by plant intracellular PRRs to initiate effector-triggered immunity (ETI). This complex host-microbe interaction is intricately intertwined with a wide range of environmental factors. For example, we found that the ambient temperature fluctuation regulates PTI and ETI in a distinct manner. We have developed an Arabidopsis cell system to express individual pathogen effectors for ETI or treat cells with purified PAMPs for PTI. In combination with enriched genetic and genomic resources in Arabidopsis, this synchronized and autonomous plant cell-single pathogen signal system holds significant promise for dissecting the complex regulation of signaling events in ETI and PTI. Our preliminary data strongly suggest the existence of differential early signaling mechanisms underlying two branches of plant innate immunity. In particular, we found that the specific members of a large gene family encoding calcium-dependent protein kinases (CDPKs) play pivotal roles in transducing calcium signature in ETI. Our proposed research will employ a multifaceted approach to further understand the signaling mechanisms underlying plant ETI and PTI.
The Specific Aims for this application are the following: 1) Decipher the distinct and convergent gene regulation in ETI and PTI;2) Elucidate the functions of CDPKs in ETI signaling;3) Dissect the ambient temperature regulation of innate immunity. Plant PTI and ETI are most similar to """"""""Toll-like receptor"""""""" and """"""""NOD-like receptor"""""""" innate immune signaling pathways in mammals respectively. Thus, our research will contribute to a general understanding of innate immunity and improve our ability to prevent and control infectious diseases.

Public Health Relevance

Understanding the intricately intertwined signal transduction networks acting downstream of various host immune sensors could provide novel avenues to prevent and control infectious diseases. Given that plant cell-surface and intracellular immune sensors are most similar to """"""""Toll-like receptor"""""""" and """"""""NOD-like receptor"""""""" in mammals respectively, our research will have broad impact on the understanding of signaling mechanisms of animal innate immunity.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM092893-04
Application #
8416398
Study Section
Molecular and Integrative Signal Transduction Study Section (MIST)
Program Officer
Dunsmore, Sarah
Project Start
2010-04-01
Project End
2015-01-31
Budget Start
2013-02-01
Budget End
2014-01-31
Support Year
4
Fiscal Year
2013
Total Cost
$242,859
Indirect Cost
$75,195
Name
Texas A&M University
Department
Biochemistry
Type
Schools of Earth Sciences/Natur
DUNS #
078592789
City
College Station
State
TX
Country
United States
Zip Code
77845
Meng, Xiangzong; Zhou, Jinggeng; Tang, Jiao et al. (2016) Ligand-Induced Receptor-like Kinase Complex Regulates Floral Organ Abscission in Arabidopsis. Cell Rep 14:1330-8
Li, Bo; Meng, Xiangzong; Shan, Libo et al. (2016) Transcriptional Regulation of Pattern-Triggered Immunity in Plants. Cell Host Microbe 19:641-50
Meng, Xiangzong; Chen, Xin; Mang, Hyunggon et al. (2015) Differential Function of Arabidopsis SERK Family Receptor-like Kinases in Stomatal Patterning. Curr Biol 25:2361-72
Feng, Baomin; Liu, Chenglong; de Oliveira, Marcos V V et al. (2015) Protein poly(ADP-ribosyl)ation regulates arabidopsis immune gene expression and defense responses. PLoS Genet 11:e1004936
Zhou, Jinggeng; Lu, Dongping; Xu, Guangyuan et al. (2015) The dominant negative ARM domain uncovers multiple functions of PUB13 in Arabidopsis immunity, flowering, and senescence. J Exp Bot 66:3353-66
Meng, Xiangzong; Shan, Libo; He, Ping (2015) Stack Heterotrimeric G Proteins and MAPK Cascades on a RACK. Mol Plant 8:1691-3
Li, Bo; Jiang, Shan; Yu, Xiao et al. (2015) Phosphorylation of trihelix transcriptional repressor ASR3 by MAP KINASE4 negatively regulates Arabidopsis immunity. Plant Cell 27:839-56
Wu, Shujing; Shan, Libo; He, Ping (2014) Microbial signature-triggered plant defense responses and early signaling mechanisms. Plant Sci 228:118-26
Zhou, Jinggeng; He, Ping; Shan, Libo (2014) Ubiquitination of plant immune receptors. Methods Mol Biol 1209:219-31
Li, Fangjun; Cheng, Cheng; Cui, Fuhao et al. (2014) Modulation of RNA polymerase II phosphorylation downstream of pathogen perception orchestrates plant immunity. Cell Host Microbe 16:748-58

Showing the most recent 10 out of 27 publications