Jean Greenberg, Ph.D.

Research Summary

My long term interest is how organisms adapt to a changing environment. The study of plant-pathogenic bacterial interactions affords a rich variety of events in which to address this problem. On the pathogen side, bacteria must adapt to the host environment, overcoming natural barriers and inducible defenses to successfully colonize and later disseminate (transmit) to new hosts. On the host side, the plant must detect the invading pathogen and activate local responses that can include programmed cell death (PCD) to contain the infection. In some cases, the host response to local infection involves long distance signaling that enables the plant to mount a faster and stronger response to secondary infections, a phenomenon called systemic acquired resistance (SAR). Plants also have mechanisms to modulate responses to infection to avoid excessive activation of responses that could have an adverse fitness cost. My research has focused on three areas: (1) pathogenic effector roles and mechanisms, (2) plant signaling mechanisms (local and long distance) and (3) plant PCD modulation and mechanisms. We study the pathogenic bacteria Pseudomonas syringae and Ralstonia solanacaerum and their interactions with multiple plant hosts, including Arabidopsis thaliana, Nicotiana benthamiana, tomato, lettuce and potato.

Selected Papers

Jelenska, J, van Hal, JA, Greenberg, JT. (2010) Pseudomonas syringae hijacks plant stress machinery for virulence. Proc Natl Acad Sci. USA 107(29):13177-82.

Jung, H.W., Tschaplinski, T.J., Wang, L., Glazebrook, J., Greenberg, J.T. (2009) Priming in systemic plant immunity.
Science 234: 89-91

Lu H., Salimian, S., Gamelin, E., Wang, G., Fedorowski, J., LaCourse, W., Greenberg, J. T. (2009) Genetic analysis of
acd6-1 reveals complex defense networks and leads to identification of novel defense genes in Arabidopsis. Plant J.
Feb 10. [epub ahead of print] PMID: 19144005

Castillo, J.A., Greenberg, J.T. (2007) Evolutionary Dynamics of Ralstonia solanacearum. Appl Environ Microbiol.
73(4):1225-1238. 

Lee, M.W., Lu, H., Jung, H.W., Greenberg, J.T. (2007) A key role for the Arabidopsis WIN3 protein in disease resistance triggered by Pseudomonas syringae that secrete AvrRpt2. Mol.
Plant Microbe Interact. 20:1192-1200.

Jelenska, J., Yao, N., Vinatzer, B.A., Wright, C.M., Brodsky, J.L., Greenberg, J.T. (2007) A J-domain virulence effector of Pseudomonas syringae remodels host chloroplasts and suppresses defenses. Current Biology 17:499-508

Vinatzer BA, Teitzel GM, Lee M-W, Jelenska J, Hotton S, Fairfax K, Jenrette J, and Greenberg JT. (2006). The Type III effector repertoire of Pseudomonas syringae pv. syringae B728a and its role in survival and disease on host and non-host plants. Mol. Micro. 62:26-44. 

Yao, N. and Greenberg, JT. Arabidopsis ACCELERATED CELL DEATH2 Modulates Programmed Cell Death. Plant Cell. 2006 18:397-411 

Lu, H., Liu, Y. and Greenberg, J.T. (2005) Structure-function analysis of the plasma membrane-localized Arabidopsis defense component ACD6. Plant J. 44:798-809 

Yao, N., Eisfelder, B. J., Marvin, J., Greenberg, J.T. (2004) The mitochondrion, an organelle commonly involved in programmed cell death in Arabidopsis thaliana. Plant J.
40:596-610.

Song, J.T., Lu, H. and Greenberg, J.T. (2004) Divergent roles in Arabidopsis development and defense of two homologous genes, ABERRANT GROWTH AND DEATH2 and AGD2-LIKE DEFENSE RESPONSE PROTEIN1, encoding novel aminotransferases. Plant Cell, 16:353-366

Vinatzer, B.A., Jelenska, J., Greenberg, J.T. (2005) Bioinformatics correctly identifies many type III secretion substrates in the plant pathogen Pseudomonas syringae and the biocontrol isolate P. fluorescens SBW25. Mol. Plant Microbe Interact. 18:877-888.

Song, J. T., Lu, H., McDowell, J. M. and Greenberg, J. T.
(2004). "A key role for ALD1 in activation of local and
systemic defenses in Arabidopsis." Plant J 40: 200-12.  

Liang, H., Yao, N., Song, J. T., Luo, S., Lu, H. and Greenberg, J. T. (2003). "Ceramides modulate programmed cell
death in plants." Genes Dev 17: 2636-41.  

Lu, H., Rate, D. N., Song, J. T. and Greenberg, J. T. (2003).
"ACD6, a novel ankyrin protein, is a regulator and an effector of salicylic acid signaling in the Arabidopsis defense response." Plant Cell 15: 2408-20. 

Guttman, D. S., Vinatzer, B. A., Sarkar, S. F., Ranall, M. V., Kettler, G. and Greenberg, J. T. (2002). "A functional screen for the type III (Hrp) secretome of the plant pathogen
Pseudomonas syringae." Science 295: 1722-6.  

Vinatzer BA, Teitzel GM, Lee M-W, Jelenska J, Hotton S, Fairfax K, Jenrette J, and Greenberg JT.  (2006). The Type III effector repertoire of Pseudomonas syringae pv. syringae B728a and its role in survival and disease on host and non-host plants.  Mol. Micro. 62:26-44.

Vinatzer BA and Greenburg JT. (2007). Whole genome analysis to identify type III-secreted effectors. Methods Mol Biol 354:19-34.

Castillo JA and Greenberg JT. (2007). Evolutionary Dynamics of Ralstonia solanacearum. Appl Environ Microbiol 73(4):1225-1238.

Jelenska J, Yao N, Vinatzer BA, Wright CM, Brodsky JL and Greenberg JT. (2007). A J-domain virulence effector of Pseudomonas syringae remodels host chloroplasts and suppresses defenses.  Current Biology 17:499-508.

Lee MW, Lu H, Jung HW and Greenberg JT. (2007).  A key role for the Arabidopsis WIN3 protein in disease resistance triggered by Pseudomonas syringae that secrete AvrRpt2. Mol Plant Microbe Interact.  20:1192-1200.

Lee MW, Jelenska J and Greenberg JT. (2008).  Arabidopsis proteins important for modulating responses to Pseudomonas syringae that secrete HopW1-1. Plant J 54(3):452-65.