Molecular Basis of Pathogen-Induced Cell Death in Plants

Summary

Principal Investigator: JEAN GREENBERG
Abstract: DESCRIPTION (provided by applicant): Experiments in this competing renewal combine the powerful genetic tools of the model plant Arabidopsis with cell biological and biochemical approaches to examine a major signaling pathway that controls innate immunity and programmed cell death (PCD). The control of plant defenses has many parallels with human innate immunity. Furthermore, PCD has similar features and regulation in plants and humans. Our long term goal is to understand the molecular basis of PCD regulation and execution. This is essential for developing strategies to manipulate PCD to prevent or cure diseases involving excess or insufficient PCD induction in both plants and humans. What is learned from studying plant immunity and PCD will be a paradigm for understanding similar events in humans. Experiments described herein build on previous work on two Arabidopsis genes, ACD6 and ACD2. ACD6 is a novel integral plasma membrane protein with an N- terminal ankyrin repeat domain that controls defense and PCD in plants. Ankyrin repeats are involved in protein-protein interactions in plants, humans and many other organisms. ACD6 is important for both local and systemic signaling during infection. ACD2 is a novel protein that controls the activation and extent of PCD during infection by controlling the levels or reactivity of an endogenous PCD-inducing molecule that is either a porphyrin or a porphyrin-like molecule. Thus, infection activates ACD6 to regulate defenses and PCD and ACD2 modulates the timing and extent of PCD to prevent excess tissue damage. The proposed research aims to: (i) determine the mechanism of action of ACD6 in activating PCD and disease resistance using molecular genetic and biochemical approaches;(2) determine the mechanism of action of ACD2 by combining molecular genetic, biochemical and physiological experiments;and (3) discern the properties and signaling requirements of cells that die due to porphyrin treatment (a surrogate for infection) using cell biological approaches. Porphyrins are important in anti-tumor therapies being developed. Therefore, it is important to know as much as possible about the effects that porphyrins have on cells. Dis-regulation of porphyrins in human (a condition called porphyria) causes severe disease to humans. ACD2 may provide a way to help people with this disease, since it likely has the potential to detoxify porphyrins. A number of human diseases are also caused by the malfunction of ankyrin-containing proteins. This work will generate important information about the whole class of ankyrin proteins that can be applied to understanding and possibly interrupting some human diseases. These studies will unravel common processes in plants and humans that can be manipulated to treat diseases caused by too much or too little cell damage. Because experimental progress using a plant model is rapid, the results obtained and quickly be related to human biology and disease.
Funding Period: 1996-05-01 - 2010-08-31
more information: NIH RePORT

Top Publications

  1. pmc A conserved cysteine motif is critical for rice ceramide kinase activity and function
    Fang Cheng Bi
    State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat Sen University, Guangzhou, China
    PLoS ONE 6:e18079. 2011
  2. pmc Multiple roles of WIN3 in regulating disease resistance, cell death, and flowering time in Arabidopsis
    Guan Feng Wang
    Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250, USA
    Plant Physiol 156:1508-19. 2011
  3. pmc Accelerated cell death 2 suppresses mitochondrial oxidative bursts and modulates cell death in Arabidopsis
    Gopal K Pattanayak
    Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
    Plant J 69:589-600. 2012
  4. pmc Type III secretion and effectors shape the survival and growth pattern of Pseudomonas syringae on leaf surfaces
    Jiyoung Lee
    Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
    Plant Physiol 158:1803-18. 2012
  5. ncbi Structure-function analysis of the plasma membrane- localized Arabidopsis defense component ACD6
    Hua Lu
    Department of Molecular Genetics and Cell Biology, The University of Chicago, IL 60637, USA
    Plant J 44:798-809. 2005
  6. pmc Arabidopsis ACCELERATED CELL DEATH2 modulates programmed cell death
    Nan Yao
    Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
    Plant Cell 18:397-411. 2006
  7. pmc Signaling pathways that regulate the enhanced disease resistance of Arabidopsis "defense, no death" mutants
    Ruth K Genger
    Department of Plant Pathology, University of Wisconsin Madison, Madison, WI 53706, USA
    Mol Plant Microbe Interact 21:1285-96. 2008
  8. pmc Genetic analysis of acd6-1 reveals complex defense networks and leads to identification of novel defense genes in Arabidopsis
    Hua Lu
    Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
    Plant J 58:401-12. 2009

Scientific Experts

  • Hua Lu
  • Jean T Greenberg
  • Nan Yao
  • Gopal K Pattanayak
  • Jiyoung Lee
  • Guan Feng Wang
  • Fang Cheng Bi
  • Ruth K Genger
  • Masakazu Sugishima
  • Gregory B Martin
  • Kathy Munkvold
  • Gail M Teitzel
  • Alison G Smith
  • Yukihiro Okamoto
  • Hitoshi Tamiaki
  • Bastien Christ
  • Olga del Pozo
  • Stefan Hortensteiner
  • Richard W Michelmore
  • Sujatha Venkataramani
  • Michael Moulin
  • Lukas Kunz
  • Gina Ng
  • Ce Fang
  • Quan Fang Zhang
  • Jin Park
  • Jian Li
  • Zhe Liu
  • Jian Bin Su
  • Safae Hamdoun
  • Savanna Seabolt
  • Hong Bin Wang
  • John M McDowell
  • Ho Won Jung
  • Grace I Jurkowski
  • Andrew F Bent

Detail Information

Publications8

  1. pmc A conserved cysteine motif is critical for rice ceramide kinase activity and function
    Fang Cheng Bi
    State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat Sen University, Guangzhou, China
    PLoS ONE 6:e18079. 2011
    ..Here, we report the characterization of a ceramide kinase, OsCERK, from rice (Oryza sativa spp. Japonica cv. Nipponbare) and investigate the effects of ceramides on rice cell viability...
  2. pmc Multiple roles of WIN3 in regulating disease resistance, cell death, and flowering time in Arabidopsis
    Guan Feng Wang
    Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250, USA
    Plant Physiol 156:1508-19. 2011
    ..They also highlight that plant innate immunity and development are closely connected processes, precise regulation of which should be important for the fitness of plants...
  3. pmc Accelerated cell death 2 suppresses mitochondrial oxidative bursts and modulates cell death in Arabidopsis
    Gopal K Pattanayak
    Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
    Plant J 69:589-600. 2012
    ..Together, the data suggest that ACD2 localizes dynamically during infection to protect cells from pro-death mobile substrate molecules, some of which may originate in chloroplasts, but have major effects on mitochondria...
  4. pmc Type III secretion and effectors shape the survival and growth pattern of Pseudomonas syringae on leaf surfaces
    Jiyoung Lee
    Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
    Plant Physiol 158:1803-18. 2012
    ..Thus, the T3SS, HopAA1, HopZ3, and plant defenses strongly influence epiphytic survival and/or growth of PsyB728a...
  5. ncbi Structure-function analysis of the plasma membrane- localized Arabidopsis defense component ACD6
    Hua Lu
    Department of Molecular Genetics and Cell Biology, The University of Chicago, IL 60637, USA
    Plant J 44:798-809. 2005
    ..A plausible scenario is that information exchange between the ankyrin and transmembrane domains is involved in activating defense signaling...
  6. pmc Arabidopsis ACCELERATED CELL DEATH2 modulates programmed cell death
    Nan Yao
    Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
    Plant Cell 18:397-411. 2006
    ....
  7. pmc Signaling pathways that regulate the enhanced disease resistance of Arabidopsis "defense, no death" mutants
    Ruth K Genger
    Department of Plant Pathology, University of Wisconsin Madison, Madison, WI 53706, USA
    Mol Plant Microbe Interact 21:1285-96. 2008
    ..The above findings indicate that the broad-spectrum resistance of dnd mutants occurs due to activation or sensitization of multiple defense pathways, yet none of the investigated pathways are required for the reduced-HR phenotype...
  8. pmc Genetic analysis of acd6-1 reveals complex defense networks and leads to identification of novel defense genes in Arabidopsis
    Hua Lu
    Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
    Plant J 58:401-12. 2009
    ..Taken together, acd6-1 is a powerful tool not only for dissecting defense regulatory networks but also for discovering novel defense genes...