Abstract Plants possess cell surface-localized immune receptors that detect microbe-associated molecular patterns (MAMPs) and initiate defenses that provide effective resistance against microbial pathogens. Many MAMP-induced signaling pathways and cellular responses are known, yet how pattern-triggered immunity (PTI) limits pathogen growth in plants is poorly understood. Through a combined metabolomics and genetics approach, we discovered that plant-exuded proline is a virulence-inducing signal and nutrient for the bacterial pathogenPseudomonas syringae, and that MAMP-induced depletion of proline from the extracellular spaces of Arabidopsis leaves directly contributes to PTI againstP. syringae. We further show that MAMP-induced depletion of extracellular proline requires the amino acid transporterLysineHistidineTransporter1(LHT1). This study demonstrates that depletion of a single extracellular metabolite is an effective component of plant induced immunity. Given the important role for amino acids as nutrients for microbial growth, their depletion at sites of infection may be a broadly effective means for defense against many pathogens.
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Natural variation in the pattern‐triggered immunity response in plants: Investigations, implications and applications
Abstract The pattern‐triggered immunity (PTI) response is triggered at the plant cell surface by the recognition of microbe‐derived molecules known as microbe‐ or pathogen‐associated molecular patterns or molecules derived from compromised host cells called damage‐associated molecular patterns. Membrane‐localized receptor proteins, known as pattern recognition receptors, are responsible for this recognition. Although much of the machinery of PTI is conserved, natural variation for the PTI response exists within and across species with respect to the components responsible for pattern recognition, activation of the response, and the strength of the response induced. This review describes what is known about this variation. We discuss how variation in the PTI response can be measured and how this knowledge might be utilized in the control of plant disease and in developing plant varieties with enhanced disease resistance.
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- Award ID(s):
- 2154872
- PAR ID:
- 10497036
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Plant Pathology
- Volume:
- 25
- Issue:
- 3
- ISSN:
- 1464-6722
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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