Natural variation in the pattern-triggered immunity response in plants: Investigations, implications and applications.

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.

A group-based behavioural intervention for weight management (PROGROUP) versus usual care in adults with severe obesity: a feasibility randomised controlled trial protocol.

Background: Approximately 15 million people in the UK live with obesity, around 5 million of whom have severe obesity (body mass index (BMI) ≥35kg/m). Having severe obesity markedly compromises health, well-being and quality of life, and substantially reduces life expectancy. These adverse outcomes are prevented or ameliorated by weight loss, for which sustained behavioural change is the cornerstone of treatment.

A Solanum lycopersicoides reference genome facilitates insights into tomato specialized metabolism and immunity.

Wild relatives of tomato are a valuable source of natural variation in tomato breeding, as many can be hybridized to the cultivated species (Solanum lycopersicum). Several, including Solanum lycopersicoides, have been crossed to S. lycopersicum for the development of ordered introgression lines (ILs), facilitating breeding for desirable traits.

Influence of Flagellin Polymorphisms, Gene Regulation, and Responsive Memory on the Motility of Species That Cause Bacterial Spot Disease of Solanaceous Plants.

Increasingly, new evidence has demonstrated variability in the epitope regions of bacterial flagellin, including in regions harboring the microbe-associated molecular patterns flg22 and flgII-28 that are recognized by the pattern recognition receptors FLS2 and FLS3, respectively. Additionally, because bacterial motility is known to contribute to pathogen virulence and chemotaxis, reductions in or loss of motility can significantly reduce bacterial fitness. In this study, we determined that variations in flg22 and flgII-28 epitopes allow some but not all spp.

Genome Sequencing and Functional Characterization of , the Causal Agent of Bacterial Spot Disease of Cucurbits.

Bacterial leaf spot disease caused by has severely affected the pumpkin industries in the Midwestern region of United States, with the bacteria mainly infecting pumpkin leaves and fruits, and leading to significant yield losses. In this study, we utilized genomics and genetics approaches to elucidate molecular mechanisms of pathogenesis during interaction with its host. We generated the first reference-quality whole-genome sequence of the type isolate and compared with other species, has a smaller genome size with fewer virulence-related genes.

Molecular Characterization of Differences between the Tomato Immune Receptors Flagellin Sensing 3 and Flagellin Sensing 2.

Plants mount defense responses by recognizing indicators of pathogen invasion, including microbe-associated molecular patterns (MAMPs). Flagellin, from the bacterial pathogen pv. tomato (), contains two MAMPs, flg22 and flgII-28, that are recognized by tomato () receptors Flagellin sensing2 (Fls2) and Fls3, respectively, but to what degree each receptor contributes to immunity and whether they promote immune responses using the same molecular mechanisms are unknown.

Survey of Sensitivity to Fatty Acid-Amino Acid Conjugates in the Solanaceae.

Plants perceive insect herbivores via a sophisticated surveillance system that detects a range of alarm signals, including herbivore-associated molecular patterns (HAMPs). Fatty acid-amino acid conjugates (FACs) are HAMPs present in oral secretions (OS) of lepidopteran larvae that induce defense responses in many plant species. In contrast to eggplant (Solanum melongena), tomato (S.

Mai1 Protein Acts Between Host Recognition of Pathogen Effectors and Mitogen-Activated Protein Kinase Signaling.

The molecular mechanisms acting between host recognition of pathogen effectors by nucleotide-binding leucine-rich repeat receptor (NLR) proteins and mitogen-activated protein kinase (MAPK) signaling cascades are unknown. MAPKKKα (M3Kα) activates MAPK signaling leading to programmed cell death (PCD) associated with NLR-triggered immunity. We identified a tomato M3Kα-interacting protein, SlMai1, that has 80% amino acid identity with brassinosteroid kinase 1 (AtBsk1).

Natural variation for unusual host responses and flagellin-mediated immunity against Pseudomonas syringae in genetically diverse tomato accessions.

The interaction between tomato and Pseudomonas syringae pv tomato (Pst) is a well-developed model for investigating the molecular basis of the plant immune system. There is extensive natural variation in Solanum lycopersicum (tomato) but it has not been fully leveraged to enhance our understanding of the tomato-Pst pathosystem. We screened 216 genetically diverse accessions of cultivated tomato and a wild tomato species for natural variation in their response to three strains of Pst.

The Locus of Confers Resistance to Race 1 Strains of pv. and to by Recognizing the Type III Effectors AvrRpt2 and RipBN.

Race 1 strains of pv. , which cause bacterial speck disease of tomato, are becoming increasingly common and no simply inherited genetic resistance to such strains is known. We discovered that a locus in , termed (), confers resistance to race 1 pv.

MAP kinases associate with high molecular weight multiprotein complexes.

Plant responses to the environment and developmental processes are mediated by a complex signaling network. The Arabidopsis thaliana mitogen-activated protein kinases (MAPKs) MPK3 and MPK6 and their orthologs in other plants are shared signal transducers that respond to many developmental and environmental signals and thus represent highly connected hubs in the cellular signaling network. In animals, specific MAPK signaling complexes are assembled which enable input-specific protein-protein interactions and thus specific signaling outcomes.

Detecting the interaction of peptide ligands with plant membrane receptors.

The field of plant receptor biology has rapidly expanded in recent years, however the demonstration of direct interaction between receptor-ligand pairs remains a challenge. Click chemistry has revolutionized small molecule research but lacks popularity in plant research. Here we describe a method that tests for the direct physical interaction of a candidate receptor protein and a peptide ligand.

Tomato receptor FLAGELLIN-SENSING 3 binds flgII-28 and activates the plant immune system.

Plants and animals detect the presence of potential pathogens through the perception of conserved microbial patterns by cell surface receptors. Certain solanaceous plants, including tomato, potato and pepper, detect flgII-28, a region of bacterial flagellin that is distinct from that perceived by the well-characterized FLAGELLIN-SENSING 2 receptor. Here we identify and characterize the receptor responsible for this recognition in tomato, called FLAGELLIN-SENSING 3.

Detecting N-myristoylation and S-acylation of host and pathogen proteins in plants using click chemistry.

Background: The plant plasma membrane is a key battleground in the war between plants and their pathogens. Plants detect the presence of pathogens at the plasma membrane using sensor proteins, many of which are targeted to this lipophilic locale by way of fatty acid modifications. Pathogens secrete effector proteins into the plant cell to suppress the plant's defense mechanisms.

Natural variation for responsiveness to flg22, flgII-28, and csp22 and Pseudomonas syringae pv. tomato in heirloom tomatoes.

Tomato (Solanum lycopersicum L.) is susceptible to many diseases including bacterial speck caused by Pseudomonas syringae pv. tomato.

Wounding systemically activates a mitogen-activated protein kinase in forage and turf grasses.

Forage and turf grasses are continually cut and grazed by livestock, however very little is known concerning the perception or molecular responses to wounding. Mechanical wounding rapidly activated a 46 kDa and a 44 kDa mitogen-activated protein kinase (MAPK) in six different grass species. In the model grass species Lolium temulentum, the 46 kDa MAPK was rapidly activated within 5 min of wounding both locally and systemically in an adjacent unwounded tiller.

The COP9 signalosome controls jasmonic acid synthesis and plant responses to herbivory and pathogens.

The COP9 signalosome (CSN) is a multi-protein complex that regulates the activities of cullin-RING E3 ubiquitin ligases (CRLs). CRLs ubiquitinate proteins in order to target them for proteasomal degradation. The CSN is required for proper plant development.

Tissue-type specific systemin perception and the elusive systemin receptor.

Systemin is a wound signaling peptide from tomato that is important for plant defenses against herbivory. The systemin receptor was initially identified as the tomato homolog of the brassinosteroid receptor BRI1, but genetic evidence argued against this finding. However, we found that BRI1 may function as an inappropriate systemin binding protein that does not activate the systemin signaling pathway.