|BA||Biology||Lawrence University||Appleton, Wis.|
|PhD||Botany and Plant Pathology||Michigan State University||East Lansing, Mich.|
Proteomics of protein phosphorylation and protein kinases; signaling and secretion during host-pathogen interactions; interactions between biotic and abiotic stress.
How Do Plants Recognize and Respond to Bacterial Pathogens?
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 within minutes after the application of microbial elicitors. This program has revealed more than 40 novel components associated with defense responses. We are using reverse genetics, biochemistry, transcriptomics, proteomics, and metabolomics to understand how these putative signaling proteins affect the plant’s resistance to bacterial pathogens.
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. We have found that the MKP1-mediated pathway leads to a novel mechanism for plant resistance whereby plants restrict chemical signals required by the bacterial pathogen to activate their virulence programs. Current work in the lab involves understanding how the plant controls the levels of these signals during a defense response.
How Do Plants Coordinate Rapid Changes in the Plasma Membrane Throughout the Plant in Response to Infections by Bacterial Pathogens?
A recent plasma membrane (PM) proteomics analysis in our lab revealed a number of proteins that rapidly decrease within one hour of the plants perception of a bacterial pathogen. Among these Iron Regulated Transporter 1 (IRT1), the main transporter responsible for iron uptake from the soil. Not only does this reveal a rapid, previously undescribed cross-talk between biotic and abiotic stress regulation, but we have also demonstrate that this regulation requires pathogen recognition in the leaves with an unknown signal being rapidly transmitted to the roots to regulate IRT1. We are currently (a) dissecting the signaling pathway(s) leading to this regulation of IRT1, and (b) defining the broader network of rapidly regulated PM proteins throughout the plant.
Notable Honors and Service
- CAFNR – Roger L. Mitchell Fellow Award, 2023
- CAFNR – Mumford Outstanding Faculty Award, 2022
- Extraordinary Professor, University of Western Cape, Cape Town, South Africa, 2019 – Present
- CAFNR Distinguished Researcher, 2019
- Fellow, American Society of Plant Biologists, 2019
- Fellow, American Association for the Advancement of Science, 2018
O’Malley MR, Kpenu E, Peck SC, Anderson JC. (2023) Plant-exuded chemical signals induce surface attachment of the bacterial pathogen Pseudomonas syringae. PeerJ 11:e14862 doi.org/10.7717/peerj.14862
Fichman Y, Zandalinas SI, Peck SC, Luan S, Mittler R. (2022) HPCA1 is required for systemic reactive oxygen species and calcium cell-to-cell signaling and plant acclimation to stress. Plant Cell 34:4453-4471 doi: 10.1093/plcell/koac241
Anderson JA, Peck SC. (2021) Primary Metabolism: It’s More than What’s for Dinner. Mol Plant 14:1219-1220. https://doi.org/10.1016/j.molp.2021.06.022
Kamiyama Y, Hirotani M, Ishikawa S, Minegishi F, Katagiri S, Rogan CJ, Takahashi F, Nomoto M, Ishikawa K, Kodama Y, Tada Y, Takezawa D, Anderson JC, Peck SC, Shinozaki K, Umezawa T. (2021) Arabidopsis group C Raf-like protein kinases negatively regulate abscisic acid signaling and are direct substrates of SnRK2. Proc Natl Acad Sci USA 118: e2100073118 doi.org/10.1073/pnas.2100073118
Collins CA, Bond L, Anderson JC, Salamango D, Smith JM, Peck SC, Heese A. (2020) EPSIN1 modulates the plasma membrane abundance of FLAGELLIN SENSING2 for effective immune responses. Plant Physiology 182: 1762-1775.
NSF IOS-1953509: “Mechanisms linking nutrient acquisition and water-soaking during bacterial infection of plants”; CoPI with PI David Mackey (Ohio State University) and CoPI Bing Yang (MU). Dates of grant: 9/1/20 – 8/31/24
NSF DEB-2217322: “IntBIO: Coordinating and integrating whole-plant responses to abiotic and biotic stress signals via changes in plasma membrane proteomes”; PI with CoPIs Antje Heese (MU) and David Mendoza (MU). Dates of grant: 9/15/22 – 8/31/25