Office: 271H Bond Life Sciences Center
Mail: Christopher S. Bond Life Sciences Center
271H Bond Life Sciences Center
University of Missouri
Columbia, MO 65211
|BA||Lawrence University||Appleton, Wis.||Biology|
|PhD||Michigan State University||East Lansing, Mich.||Botany and Plant Pathology|
PAMP Signaling and Responses
The perception of and response to microbial signal molecules is a vital strategy evolved by plants to survive attacks by potential pathogens. Substantial evidence exists for the requirement of phosphorylation to initiate a range of defense-related responses. The identity of the phosphorylated proteins and their role in defense, however, remains largely unknown. To uncover new subsets of signaling candidates, my laboratory has developed complementary proteomic approaches to identify proteins undergoing phosphorylation in Arabidopsis cells within minutes after the application of microbial elicitors. This program has revealed more than 40 novel components associated with defense responses. We have also used reverse genetics to demonstrate that at least some of these phosphoproteins play important roles in resistance to microbes. Our next goal is to complete the pathways linking elicitor perception to the phosphorylation of these signaling components.
A major focus of the lab is characterization of a mutant in MAP Kinase Phosphatase 1 (MKP1). Plants lacking a functional MKP1 have enhanced PAMP responses and enhanced resistance, indicating that MKP1 is a negative regulator of plant defense. Importantly, phenotypes in the mkp1 mutant are suppressed by a second mutation in a specific MAP Kinase, MPK6. The potentiated responses in the mkp1 mutant provide an important model for delineating signaling events downstream of MPK6. We are currently investigating the mode of action underlying enhanced resistance in the mkp1 mutant.
Our lab is also interested in how plants respond to drought and/or decreased water availability. We are investigating ABA responses in stomata of Brassica, particularly in regards to changes in protein composition and protein modifications. In addition, phosphoproteomic analyses of Arabidopsis seedlings in response to ABA or dehydration revealed partially distinct signaling pathways responding to these stresses. Interestingly, we also found overlap between ABA-regulated phosphoproteins and those involved in biotic stress responses. These results indicate that some portions of the signaling pathways are co-utilized by biotic and abiotic stresses yet are integrated differently to effect distinct biological responses.
We are also investigating how the plasma membrane (PM) proteome changes in the primary roots of maize during water stress to gain insights into possible reorganization of transporters and other PM proteins that may play roles in adaptation to drought. A better understanding of root responses that contribute to maintaining growth under low water potential could lead to crops with improved yield under limiting conditions.
Umezawa T, Sugiyama N, Anderson JC, Takahashi F, Jikumaru Y, Kamiya Y, Ishihama Y, Peck SC, and Shinozaki K. Integrating genetics and phosphoproteomics reveals protein phosphorylation network of the core ABA signaling pathway in Arabidopsis. Science Signaling. 6:rs8 doi: 10.1126/scisignal.2003509 (2013).
Zhang Z, Voothuluru P, Yamaguchi M, Sharp RE and Peck SC. Developmental distribution of plasma membrane-enriched proteome in the maize primary root growth zone. Frontiers in Plant Proteomics. 4:33 doi: 10.3389/fpls.2013.00033 (2013).
Sörensson C, Lenman M, Schopper S, Veide-Vilg J, Ljungdahl T, Grøtli M, Tamás MJ, Peck SC and Andreasson E. Screen for new substrates of the Arabidopsis MAP kinases, MPK3 and MPK6, identifies a novel protein participating in stomatal patterning. Biochem J. 446:271-278 (2012).
Anderson JC, Bartels S, González Besteiro MA, Shahollari B, Ulm R, Peck SC. Arabidopsis MAPK Phosphatase 1 negatively regulates PAMP responses and basal resistance to Pseudomonas syringae. Plant J. 67: 258-268 (2011).
Nühse TS, Bottrill AR, Jones AME, Peck SC. Quantitative phosphoproteomic analysis of plasma membrane proteins reveals regulatory mechanisms of plant innate immune responses Plant J. 51: 931-940 (2007).
Kalde M, Nuhse TS, Findley K, Peck SC. The syntaxin SYP132 contributes to plant resistance against bacteria and secretion of pathogenesis-related protein 1 (PR1) Proc. Natl. Acad. Sci. USA. 104: 11850-11855 (2007).