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Sheng-Yang He

Benjamin E. Powell Distinguished Professor of Biology
Biology
Office hours 9 am - 5 pm daily  

Selected Publications


Rapid intracellular acidification is a plant defense response countered by the brown planthopper.

Journal Article Current biology : CB · November 2024 The brown planthopper (BPH) is the most destructive insect pest in rice. Through a stylet, BPH secretes a plethora of salivary proteins into rice phloem cells as a crucial step of infestation. However, how various salivary proteins function in rice cells t ... Full text Cite

Roles of microbiota in autoimmunity in Arabidopsis leaves.

Journal Article Nature plants · September 2024 Over the past three decades, researchers have isolated plant mutants that show constitutively activated defence responses in the absence of pathogen infection. These mutants are called autoimmune mutants and are typically dwarf and/or bearing chlorotic/nec ... Full text Cite

The conserved AvrE family of bacterial effectors: functions and targets during pathogenesis

Journal Article Trends in Microbiology · January 1, 2024 The AvrE family of type III secreted effectors are highly conserved among many agriculturally important phytopathogenic bacteria. Despite their critical roles in the pathogenesis of phytopathogenic bacteria, the molecular functions and virulence mechanisms ... Full text Cite

Small proteins modulate ion-channel-like ACD6 to regulate immunity in Arabidopsis thaliana.

Journal Article Molecular cell · December 2023 The multi-pass transmembrane protein ACCELERATED CELL DEATH 6 (ACD6) is an immune regulator in Arabidopsis thaliana with an unclear biochemical mode of action. We have identified two loci, MODULATOR OF HYPERACTIVE ACD6 1 (MHA1) and its paralog MHA1-LIKE (M ... Full text Cite

Defense against phytopathogens relies on efficient antimicrobial protein secretion mediated by the microtubule-binding protein TGNap1.

Journal Article Nature communications · October 2023 Plant immunity depends on the secretion of antimicrobial proteins, which occurs through yet-largely unknown mechanisms. The trans-Golgi network (TGN), a hub for intracellular and extracellular trafficking pathways, and the cytoskeleton, which is required f ... Full text Cite

A critical role of a eubiotic microbiota in gating proper immunocompetence in Arabidopsis.

Journal Article Nature plants · September 2023 Although many studies have shown that microbes can ectopically stimulate or suppress plant immune responses, the fundamental question of whether the entire preexisting microbiota is indeed required for proper development of plant immune response remains un ... Full text Cite

Bacterial pathogens deliver water- and solute-permeable channels to plant cells.

Journal Article Nature · September 2023 Many animal- and plant-pathogenic bacteria use a type III secretion system to deliver effector proteins into host cells1,2. Elucidation of how these effector proteins function in host cells is critical for understanding infectious diseases in animals and p ... Full text Open Access Link to item Cite

Roles of microbiota in autoimmunity in Arabidopsis.

Journal Article bioRxiv · July 4, 2023 Over the past three decades, researchers have isolated plant mutants that display constitutively activated defense responses in the absence of pathogen infection. These mutants are called autoimmune mutants and are typically dwarf and/or bearing chlorotic/ ... Full text Link to item Cite

Phyllosphere Microbiome.

Journal Article Annual review of plant biology · May 2023 The aboveground parts of terrestrial plants are colonized by a variety of microbes that collectively constitute the phyllosphere microbiota. Decades of pioneering work using individual phyllosphere microbes, including commensals and pathogens, have provide ... Full text Cite

NLR surveillance of pathogen interference with hormone receptors induces immunity.

Journal Article Nature · January 2023 Phytohormone signalling pathways have an important role in defence against pathogens mediated by cell-surface pattern recognition receptors and intracellular nucleotide-binding leucine-rich repeat class immune receptors1,2 (NLR). Pathogens have ... Full text Cite

The role of photorespiration in plant immunity.

Journal Article Frontiers in plant science · January 2023 To defend themselves in the face of biotic stresses, plants employ a sophisticated immune system that requires the coordination of other biological and metabolic pathways. Photorespiration, a byproduct pathway of oxygenic photosynthesis that spans multiple ... Full text Cite

SnRK1A-mediated phosphorylation of a cytosolic ATPase positively regulates rice innate immunity and is inhibited by Ustilaginoidea virens effector SCRE1.

Journal Article The New phytologist · November 2022 Rice false smut caused by Ustilaginoidea virens is becoming one of the most recalcitrant rice diseases worldwide. However, the molecular mechanisms underlying rice immunity against U. virens remain unknown. Using genetic, biochemical and disease resistance ... Full text Cite

Increasing the resilience of plant immunity to a warming climate.

Journal Article Nature · July 2022 Extreme weather conditions associated with climate change affect many aspects of plant and animal life, including the response to infectious diseases. Production of salicylic acid (SA), a central plant defence hormone1-3, is particularly vulnera ... Full text Cite

Growth-defense trade-offs in plants.

Journal Article Current biology : CB · June 2022 Walking through a garden or a crop field, you may notice that plants damaged by pests (insects or pathogens) look smaller than the same kind of plants nearby that are not damaged. An obvious explanation would be that damaged plants may have lost substantia ... Full text Cite

Phytocytokine signalling reopens stomata in plant immunity and water loss.

Journal Article Nature · May 2022 Stomata exert considerable effects on global carbon and water cycles by mediating gas exchange and water vapour1,2. Stomatal closure prevents water loss in response to dehydration and limits pathogen entry3,4. However, prolonged stoma ... Full text Cite

The bacterial effector AvrRxo1 inhibits vitamin B6 biosynthesis to promote infection in rice.

Journal Article Plant communications · May 2022 Xanthomonas oryzae pv. oryzicola (Xoc), which causes rice bacterial leaf streak, invades leaves mainly through stomata, which are often closed as a plant immune response against pathogen invasion. How Xoc overcomes stomatal immunity is unclear. Here, we sh ... Full text Open Access Cite

Shared in planta population and transcriptomic features of nonpathogenic members of endophytic phyllosphere microbiota.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · April 2022 SignificancePlants evolved in an environment colonized by a vast number of microbes, which collectively constitute the plant microbiota. The majority of microbiota taxa are nonpathogenic and may be beneficial to plants under certain ecological or environme ... Full text Cite

Evolutionarily conserved bacterial effectors hijack abscisic acid signaling to induce an aqueous environment in the apoplast.

Journal Article Cell host & microbe · April 2022 High atmospheric humidity levels profoundly impact host-pathogen interactions in plants by enabling the establishment of an aqueous living space that benefits pathogens. The effectors HopM1 and AvrE1 of the bacterial pathogen Pseudomonas syringae have been ... Full text Cite

Ectopic Expression of OsJAZs Alters Plant Defense and Development.

Journal Article International journal of molecular sciences · April 2022 A key step in jasmonic acid (JA) signaling is the ligand-dependent assembly of a coreceptor complex comprising the F-box protein COI1 and JAZ transcriptional repressors. The assembly of this receptor complex results in proteasome-mediated degradation of JA ... Full text Open Access Cite

An MKP-MAPK protein phosphorylation cascade controls vascular immunity in plants.

Journal Article Science advances · March 2022 Global crop production is greatly reduced by vascular diseases. These diseases include bacterial blight of rice and crucifer black rot caused by Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas campestris pv. campestris Full text Cite

Stomata facilitate foliar sorption of silver nanoparticles by Arabidopsis thaliana.

Journal Article Environmental pollution (Barking, Essex : 1987) · January 2022 Application of nanopesticides may substantially increase surface attachment and internalization of engineered nanoparticles (ENPs) in food crops. This study investigated the role of stomata in the internalization of silver nanoparticles (Ag NPs) using absc ... Full text Cite

ROLE OF THE TYPE III PROTEIN SECRETION SYSTEM IN BACTERIAL INFECTION OF PLANTS

Chapter · January 1, 2022 In the past two decades, research into the molecular basis of bacterial pathogenesis has led to the conclusion that although different bacteria may use unique mechanisms to subvert hosts, a few strategies are common. One striking example is the discovery t ... Full text Cite

Dual transcriptomic analysis reveals metabolic changes associated with differential persistence of human pathogenic bacteria in leaves of Arabidopsis and lettuce.

Journal Article G3 (Bethesda, Md.) · December 2021 Understanding the molecular determinants underlying the interaction between the leaf and human pathogenic bacteria is key to provide the foundation to develop science-based strategies to prevent or decrease the pathogen contamination of leafy greens. In th ... Full text Open Access Cite

Oxicam-type non-steroidal anti-inflammatory drugs inhibit NPR1-mediated salicylic acid pathway.

Journal Article Nature communications · December 2021 Nonsteroidal anti-inflammatory drugs (NSAIDs), including salicylic acid (SA), target mammalian cyclooxygenases. In plants, SA is a defense hormone that regulates NON-EXPRESSOR OF PATHOGENESIS RELATED GENES 1 (NPR1), the master transcriptional regulator of ... Full text Open Access Cite

Indicator species characterization and removal in a detention pond in the Plaster Creek watershed.

Journal Article Journal of environmental management · November 2021 Microbial pathogen contamination is a leading cause of impairment for urban rivers and streams in Michigan. Reports on the ability of green infrastructure best management practices to remove microbial pathogens have been highly variable. This study evaluat ... Full text Cite

A bacterial kinase phosphorylates OSK1 to suppress stomatal immunity in rice.

Journal Article Nature communications · September 2021 The Xanthomonas outer protein C2 (XopC2) family of bacterial effectors is widely found in plant pathogens and Legionella species. However, the biochemical activity and host targets of these effectors remain enigmatic. Here we show that ectopic expression o ... Full text Cite

FERONIA restricts Pseudomonas in the rhizosphere microbiome via regulation of reactive oxygen species.

Journal Article Nature plants · May 2021 Maintaining microbiome structure is critical for the health of both plants and animals. By re-screening a collection of Arabidopsis mutants affecting root immunity and hormone crosstalk, we identified a FERONIA (FER) receptor kinase mutant (fer-8) with a r ... Full text Cite

Peat-based gnotobiotic plant growth systems for Arabidopsis microbiome research.

Journal Article Nature protocols · May 2021 The complex structure and function of a plant microbiome are driven by many variables, including the environment, microbe-microbe interactions and host factors. Likewise, resident microbiota can influence many host phenotypes. Gnotobiotic growth systems an ... Full text Cite

Crops of the future: building a climate-resilient plant immune system.

Journal Article Current opinion in plant biology · April 2021 Featured Publication A grand challenge facing plant scientists today is to find innovative solutions to increase global crop production in the context of an increasingly warming climate. A major roadblock to global food sufficiency is persistent loss of crops to plant diseases ... Full text Cite

Pattern-recognition receptors are required for NLR-mediated plant immunity.

Journal Article Nature · April 2021 Featured Publication The plant immune system is fundamental for plant survival in natural ecosystems and for productivity in crop fields. Substantial evidence supports the prevailing notion that plants possess a two-tiered innate immune system, called pattern-triggered immunit ... Full text Cite

Toward understanding microbiota homeostasis in the plant kingdom.

Journal Article PLoS pathogens · April 2021 A diverse community of microorganisms inhabits various parts of a plant. Recent findings indicate that perturbations to the normal microbiota can be associated with positive and negative effects on plant health. In this review, we discuss these findings in ... Full text Cite

Arabidopsis calcium-dependent protein kinase 3 regulates actin cytoskeleton organization and immunity.

Journal Article Nature communications · December 2020 Featured Publication Pattern-triggered immunity and effector-triggered immunity are two primary forms of innate immunity in land plants. The molecular components and connecting nodes of pattern-triggered immunity and effector-triggered immunity are not fully understood. Here, ... Full text Cite

Citrus CsACD2 Is a Target of Candidatus Liberibacter Asiaticus in Huanglongbing Disease.

Journal Article Plant physiology · October 2020 Citrus Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus (Las), is one of the most destructive citrus diseases worldwide, yet how Las causes HLB is poorly understood. Here we show that a Las-secreted protein, SDE15 (CLIBASIA_04025), s ... Full text Cite

Oxicam-type nonsteroidal anti-inflammatory drugs inhibit NPR1-mediated salicylic acid pathway

Journal Article · September 25, 2020 AbstractSalicylic acid (SA) and its structural analogs are nonsteroidal anti-inflammatory drugs (NSAIDs) that target mammalian cyclooxygenases. In plants, SA acts as a defense hormone that regulates NON-EXPRESSOR OF PATHOGE ... Full text Cite

A plant genetic network for preventing dysbiosis in the phyllosphere.

Journal Article Nature · April 2020 The aboveground parts of terrestrial plants, collectively called the phyllosphere, have a key role in the global balance of atmospheric carbon dioxide and oxygen. The phyllosphere represents one of the most abundant habitats for microbiota colonization. Wh ... Full text Open Access Cite

Pathogenic Bacteria Target Plant Plasmodesmata to Colonize and Invade Surrounding Tissues.

Journal Article The Plant cell · March 2020 A hallmark of multicellular organisms is their ability to maintain physiological homeostasis by communicating among cells, tissues, and organs. In plants, intercellular communication is largely dependent on plasmodesmata (PD), which are membrane-lined chan ... Full text Cite

Crystallization of a Complex Between MYC and Jas Motif.

Chapter · January 2020 In the jasmonate signaling pathway, a region of 17 amino acids within the Jas motif of JAZ proteins and a conserved region within the N-terminus of MYC proteins are sufficient for JAZ-MYC interactions. Crystal structures of Jas-MYC complexes have revealed ... Full text Cite

Challenging battles of plants with phloem-feeding insects and prokaryotic pathogens.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · November 2019 For the past 4 decades, intensive molecular studies of mostly leaf mesophyll cell-infecting pathogens and chewing insects have led to compelling models of plant-pathogen and plant-insect interactions. Yet, some of the most devastating pathogens and insect ... Full text Cite

Plant-Microbe Interactions Facing Environmental Challenge.

Journal Article Cell host & microbe · August 2019 In the past four decades, tremendous progress has been made in understanding how plants respond to microbial colonization and how microbial pathogens and symbionts reprogram plant cellular processes. In contrast, our knowledge of how environmental conditio ... Full text Cite

An important role of l-fucose biosynthesis and protein fucosylation genes in Arabidopsis immunity.

Journal Article The New phytologist · April 2019 Plants mount coordinated immune responses to defend themselves against pathogens. However, the cellular components required for plant immunity are not fully understood. The jasmonate-mimicking coronatine (COR) toxin produced by Pseudomonas syringae pv. tom ... Full text Cite

Correction to Supporting Information for Nobori et al., Transcriptome landscape of a bacterial pathogen under plant immunity.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · December 2018 Full text Cite

Draft genome of the fungicidal biological control agent Burkholderia anthina strain XXVI.

Journal Article Archives of microbiology · July 2018 Burkholderia anthina XXVI is a rhizosphere bacterium isolated from a mango orchard in Mexico. This strain has a significant biological control activity against the causal agent of mango anthracnose, Colletotrichum gloeosporioides, likely through the produc ... Full text Cite

Salicylic acid-independent role of NPR1 is required for protection from proteotoxic stress in the plant endoplasmic reticulum.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · May 2018 The unfolded protein response (UPR) is an ancient signaling pathway designed to protect cells from the accumulation of unfolded and misfolded proteins in the endoplasmic reticulum (ER). Because misregulation of the UPR is potentially lethal, a stringent su ... Full text Cite

Pseudomonas syringae: what it takes to be a pathogen.

Journal Article Nature reviews. Microbiology · May 2018 Pseudomonas syringae is one of the best-studied plant pathogens and serves as a model for understanding host-microorganism interactions, bacterial virulence mechanisms and host adaptation of pathogens as well as microbial evolution, ecology and epidemiolog ... Full text Cite

Plant-Pathogen Warfare under Changing Climate Conditions.

Journal Article Current biology : CB · May 2018 Global environmental changes caused by natural and human activities have accelerated in the past 200 years. The increase in greenhouse gases is predicted to continue to raise global temperature and change water availability in the 21st century. ... Full text Cite

Transcriptome landscape of a bacterial pathogen under plant immunity.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · March 2018 Plant pathogens can cause serious diseases that impact global agriculture. The plant innate immunity, when fully activated, can halt pathogen growth in plants. Despite extensive studies into the molecular and genetic bases of plant immunity against pathoge ... Full text Cite

The role of water in plant-microbe interactions.

Journal Article The Plant journal : for cell and molecular biology · February 2018 Throughout their life plants are associated with various microorganisms, including commensal, symbiotic and pathogenic microorganisms. Pathogens are genetically adapted to aggressively colonize and proliferate in host plants to cause disease. However, dise ... Full text Cite

Dual impact of elevated temperature on plant defence and bacterial virulence in Arabidopsis.

Journal Article Nature communications · November 2017 Environmental conditions profoundly affect plant disease development; however, the underlying molecular bases are not well understood. Here we show that elevated temperature significantly increases the susceptibility of Arabidopsis to Pseudomonas syringae ... Full text Open Access Cite

Regulation of growth-defense balance by the JASMONATE ZIM-DOMAIN (JAZ)-MYC transcriptional module.

Journal Article The New phytologist · September 2017 The plant hormone jasmonate (JA) promotes the degradation of JASMONATE ZIM-DOMAIN (JAZ) proteins to relieve repression on diverse transcription factors (TFs) that execute JA responses. However, little is known about how combinatorial complexity among JAZ-T ... Full text Open Access Cite

Stomatal Defense a Decade Later.

Journal Article Plant physiology · June 2017 Full text Cite

Diverse mechanisms of resistance to Pseudomonas syringae in a thousand natural accessions of Arabidopsis thaliana.

Journal Article The New phytologist · June 2017 Plants are continuously threatened by pathogen attack and, as such, they have evolved mechanisms to evade, escape and defend themselves against pathogens. However, it is not known what types of defense mechanisms a plant would already possess to defend aga ... Full text Cite

Jasmonate signaling and manipulation by pathogens and insects.

Journal Article Journal of experimental botany · March 2017 Plants synthesize jasmonates (JAs) in response to developmental cues or environmental stresses, in order to coordinate plant growth, development or defense against pathogens and herbivores. Perception of pathogen or herbivore attack promotes synthesis of j ... Full text Cite

Structural insights into alternative splicing-mediated desensitization of jasmonate signaling.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · February 2017 Jasmonate ZIM-domain (JAZ) transcriptional repressors play a key role in regulating jasmonate (JA) signaling in plants. Below a threshold concentration of jasmonoyl isoleucine (JA-Ile), the active form of JA, the C-terminal Jas motif of JAZ proteins binds ... Full text Cite

Subcellular Localization of Pseudomonas syringae pv. tomato Effector Proteins in Plants.

Chapter · January 2017 Animal and plant pathogenic bacteria use type III secretion systems to translocate proteinaceous effectors to subvert innate immunity of their host organisms. Type III secretion/effector systems are a crucial pathogenicity factor in many bacterial pathogen ... Full text Cite

Leucine-rich-repeat-containing variable lymphocyte receptors as modules to target plant-expressed proteins.

Journal Article Plant methods · January 2017 BackgroundThe ability to target and manipulate protein-based cellular processes would accelerate plant research; yet, the technology to specifically and selectively target plant-expressed proteins is still in its infancy. Leucine-rich repeats (LRR ... Full text Cite

Bacteria establish an aqueous living space in plants crucial for virulence.

Journal Article Nature · November 2016 High humidity has a strong influence on the development of numerous diseases affecting the above-ground parts of plants (the phyllosphere) in crop fields and natural ecosystems, but the molecular basis of this humidity effect is not understood. Previous st ... Full text Cite

Allelic diversity in an NLR gene BPH9 enables rice to combat planthopper variation.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · November 2016 Brown planthopper (BPH), Nilaparvata lugens StÃ¥l, is one of the most devastating insect pests of rice (Oryza sativa L.). Currently, 30 BPH-resistance genes have been genetically defined, most of which are clustered on specific chromosome regi ... Full text Cite

Salicylic acid receptors activate jasmonic acid signalling through a non-canonical pathway to promote effector-triggered immunity.

Journal Article Nature communications · October 2016 It is an apparent conundrum how plants evolved effector-triggered immunity (ETI), involving programmed cell death (PCD), as a major defence mechanism against biotrophic pathogens, because ETI-associated PCD could leave them vulnerable to necrotrophic patho ... Full text Open Access Cite

The Pseudomonas syringae Type III Effector HopG1 Induces Actin Remodeling to Promote Symptom Development and Susceptibility during Infection.

Journal Article Plant physiology · July 2016 The plant cytoskeleton underpins the function of a multitude of cellular mechanisms, including those associated with developmental- and stress-associated signaling processes. In recent years, the actin cytoskeleton has been demonstrated to play a key role ... Full text Cite

Alternative Splicing of Rice WRKY62 and WRKY76 Transcription Factor Genes in Pathogen Defense.

Journal Article Plant physiology · June 2016 The WRKY family of transcription factors (TFs) functions as transcriptional activators or repressors in various signaling pathways. In this study, we discovered that OsWRKY62 and OsWRKY76, two genes of the WRKY IIa subfamily, undergo constitutive and induc ... Full text Cite

Host target modification as a strategy to counter pathogen hijacking of the jasmonate hormone receptor.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · November 2015 In the past decade, characterization of the host targets of pathogen virulence factors took a center stage in the study of pathogenesis and disease susceptibility in plants and humans. However, the impressive knowledge of host targets has not been broadly ... Full text Cite

Pseudomonas syringae Effector Avirulence Protein E Localizes to the Host Plasma Membrane and Down-Regulates the Expression of the NONRACE-SPECIFIC DISEASE RESISTANCE1/HARPIN-INDUCED1-LIKE13 Gene Required for Antibacterial Immunity in Arabidopsis.

Journal Article Plant physiology · September 2015 Many bacterial pathogens of plants and animals deliver effector proteins into host cells to promote infection. Elucidation of how pathogen effector proteins function not only is critical for understanding bacterial pathogenesis but also provides a useful t ... Full text Cite

Structural basis of JAZ repression of MYC transcription factors in jasmonate signalling.

Journal Article Nature · September 2015 The plant hormone jasmonate plays crucial roles in regulating plant responses to herbivorous insects and microbial pathogens and is an important regulator of plant growth and development. Key mediators of jasmonate signalling include MYC transcription fact ... Full text Open Access Cite

A host plant genome (Zizania latifolia) after a century-long endophyte infection.

Journal Article Plant J · August 2015 Despite the importance of host-microbe interactions in natural ecosystems, agriculture and medicine, the impact of long-term (especially decades or longer) microbial colonization on the dynamics of host genomes is not well understood. The vegetable crop 'J ... Full text Link to item Cite

Growth-defense tradeoffs in plants: a balancing act to optimize fitness.

Journal Article Molecular plant · August 2014 Growth-defense tradeoffs are thought to occur in plants due to resource restrictions, which demand prioritization towards either growth or defense, depending on external and internal factors. These tradeoffs have profound implications in agriculture and na ... Full text Cite

Temporal Dynamics of Growth and Photosynthesis Suppression in Response to Jasmonate Signaling.

Journal Article Plant physiology · July 2014 Biotic stress constrains plant productivity in natural and agricultural ecosystems. Repression of photosynthetic genes is a conserved plant response to biotic attack, but how this transcriptional reprogramming is linked to changes in photosynthesis and the ... Full text Cite

The bacterial effector HopM1 suppresses PAMP-triggered oxidative burst and stomatal immunity.

Journal Article The New phytologist · April 2014 Successful pathogens counter immunity at multiple levels, mostly through the action of effectors. Pseudomonas syringae secretes c. 30 effectors, some of which have been shown to inhibit plant immunity triggered upon perception of conserved pathogen-associa ... Full text Cite

A bacterial tyrosine phosphatase inhibits plant pattern recognition receptor activation.

Journal Article Science (New York, N.Y.) · March 2014 Innate immunity relies on the perception of pathogen-associated molecular patterns (PAMPs) by pattern-recognition receptors (PRRs) located on the host cell's surface. Many plant PRRs are kinases. Here, we report that the Arabidopsis receptor kinase EF-TU R ... Full text Cite

Bacterial effector activates jasmonate signaling by directly targeting JAZ transcriptional repressors.

Journal Article PLoS pathogens · October 2013 Gram-negative bacterial pathogens deliver a variety of virulence proteins through the type III secretion system (T3SS) directly into the host cytoplasm. These type III secreted effectors (T3SEs) play an essential role in bacterial infection, mainly by targ ... Full text Open Access Cite

Induction and suppression of PEN3 focal accumulation during Pseudomonas syringae pv. tomato DC3000 infection of Arabidopsis.

Journal Article Molecular plant-microbe interactions : MPMI · August 2013 The pleiotropic drug resistance (PDR) proteins belong to the super-family of ATP-binding cassette (ABC) transporters. AtPDR8, also called PEN3, is required for penetration resistance of Arabidopsis to nonadapted powdery mildew fungi. During fungal infectio ... Full text Cite

Molecular evidence for dual pyrethroid-receptor sites on a mosquito sodium channel.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 2013 Pyrethroid insecticides are widely used as one of the most effective control measures in the global fight against agricultural arthropod pests and mosquito-borne diseases, including malaria and dengue. They exert toxic effects by altering the function of v ... Full text Cite

Negative feedback control of jasmonate signaling by an alternative splice variant of JAZ10.

Journal Article Plant physiology · June 2013 The plant hormone jasmonate (JA) activates gene expression by promoting ubiquitin-dependent degradation of jasmonate ZIM domain (JAZ) transcriptional repressor proteins. A key feature of all JAZ proteins is the highly conserved Jas motif, which mediates bo ... Full text Cite

Pseudomonas syringae infection assays in Arabidopsis.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2013 Pseudomonas syringae pv. tomato DC30000 (Pst DC3000) infection of Arabidopsis thaliana has been widely used to elucidate many of the general principles underlying the plant immune response and bacterial pathogenesis. Study of Pst DC3000 virulence factors h ... Full text Cite

Pseudomonas syringae pv. tomato DC3000: a model pathogen for probing disease susceptibility and hormone signaling in plants.

Journal Article Annual review of phytopathology · January 2013 Since the early 1980s, various strains of the gram-negative bacterial pathogen Pseudomonas syringae have been used as models for understanding plant-bacterial interactions. In 1991, a P. syringae pathovar tomato (Pst) strain, DC3000, was reported to infect ... Full text Cite

Transcription factor-dependent nuclear localization of a transcriptional repressor in jasmonate hormone signaling.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · December 2012 The plant hormone jasmonate (JA) plays an important role in regulating growth, development and immunity. A key step in JA signaling is ligand-dependent assembly of a coreceptor complex consisting of the F-box protein COI1 and JAZ transcriptional repressors ... Full text Cite

The long-sought-after salicylic acid receptors.

Journal Article Molecular plant · September 2012 Full text Cite

Coronatine promotes Pseudomonas syringae virulence in plants by activating a signaling cascade that inhibits salicylic acid accumulation.

Journal Article Cell host & microbe · June 2012 Phytopathogens can manipulate plant hormone signaling to access nutrients and counteract defense responses. Pseudomonas syringae produces coronatine, a toxin that mimics the plant hormone jasmonic acid isoleucine and promotes opening of stomata for bacteri ... Full text Cite

Ultra-broadband microwave metamaterial absorber

Journal Article Applied Physics Letters · March 5, 2012 A microwave ultra-broadband polarization-independent metamaterial absorber is demonstrated. It is composed of a periodic array of metal-dielectric multilayered quadrangular frustum pyramids. These pyramids possess resonant absorption modes at multi ... Full text Open Access Cite

A critical role of STAYGREEN/Mendel's I locus in controlling disease symptom development during Pseudomonas syringae pv tomato infection of Arabidopsis.

Journal Article Plant physiology · December 2011 Production of disease symptoms represents the final phase of infectious diseases and is a main cause of crop loss and/or marketability. However, little is known about the molecular basis of disease symptom development. In this study, a genetic screening wa ... Full text Cite

A genetic screen reveals Arabidopsis stomatal and/or apoplastic defenses against Pseudomonas syringae pv. tomato DC3000.

Journal Article PLoS pathogens · October 2011 Bacterial infection of plants often begins with colonization of the plant surface, followed by entry into the plant through wounds and natural openings (such as stomata), multiplication in the intercellular space (apoplast) of the infected tissues, and dis ... Full text Open Access Cite

Localization of DIR1 at the tissue, cellular and subcellular levels during Systemic Acquired Resistance in Arabidopsis using DIR1:GUS and DIR1:EGFP reporters.

Journal Article BMC plant biology · September 2011 BackgroundSystemic Acquired Resistance (SAR) is an induced resistance response to pathogens, characterized by the translocation of a long-distance signal from induced leaves to distant tissues to prime them for increased resistance to future infec ... Full text Open Access Cite

Effector-triggered immunity blocks pathogen degradation of an immunity-associated vesicle traffic regulator in Arabidopsis.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · June 2011 Innate immunity in plants can be triggered by microbe- and pathogen-associated molecular patterns. The pathogen-associated molecular pattern-triggered immunity (PTI) is often suppressed by pathogen effectors delivered into the host cell. Plants can overcom ... Full text Cite

Genome sequence of the plant-pathogenic bacterium Dickeya dadantii 3937.

Journal Article Journal of bacteriology · April 2011 Dickeya dadantii is a plant-pathogenic enterobacterium responsible for the soft rot disease of many plants of economic importance. We present here the sequence of strain 3937, a strain widely used as a model system for research on the molecular biology and ... Full text Cite

Jasmonate perception by inositol-phosphate-potentiated COI1-JAZ co-receptor.

Journal Article Nature · November 2010 Jasmonates are a family of plant hormones that regulate plant growth, development and responses to stress. The F-box protein CORONATINE INSENSITIVE 1 (COI1) mediates jasmonate signalling by promoting hormone-dependent ubiquitylation and degradation of tran ... Full text Open Access Cite

Plant stomata: a checkpoint of host immunity and pathogen virulence.

Journal Article Current opinion in biotechnology · October 2010 Stomata are microscopic pores formed by pairs of guard cells in the epidermis of terrestrial plants; they are essential for gas exchange with the environment and controlling water loss. Accordingly, plants regulate stomatal aperture in response to environm ... Full text Cite

A prominent role of the flagellin receptor FLAGELLIN-SENSING2 in mediating stomatal response to Pseudomonas syringae pv tomato DC3000 in Arabidopsis.

Journal Article Plant physiology · July 2010 The FLAGELLIN-SENSING2 (FLS2) receptor kinase recognizes bacterial flagellin and initiates a battery of downstream defense responses to reduce bacterial invasion through stomata in the epidermis and bacterial multiplication in the apoplast of infected plan ... Full text Cite

Broad-spectrum defense against plant pathogens.

Journal Article Nature biotechnology · April 2010 Full text Cite

Battling immune kinases in plants.

Journal Article Cell host & microbe · April 2010 As part of innate immune signaling, plants employ a suite of receptors, kinases, and resistance proteins to recognize pathogen-derived effector proteins. In this issue of Cell Host & Microbe, Zhang et al. provide evidence refining the link between multiple ... Full text Cite

Type III protein secretion in plant pathogenic bacteria.

Journal Article Plant physiology · August 2009 Full text Cite

Multiple activities of the plant pathogen type III effector proteins WtsE and AvrE require WxxxE motifs.

Journal Article Molecular plant-microbe interactions : MPMI · June 2009 The broadly conserved AvrE-family of type III effectors from gram-negative plant-pathogenic bacteria includes important virulence factors, yet little is known about the mechanisms by which these effectors function inside plant cells to promote disease. We ... Full text Cite

Innate immunity in plants: an arms race between pattern recognition receptors in plants and effectors in microbial pathogens.

Journal Article Science (New York, N.Y.) · May 2009 For many years, research on a suite of plant defense responses that begin when plants are exposed to general microbial elicitors was underappreciated, for a good reason: There has been no critical experimental demonstration of their importance in mediating ... Full text Cite

Subcellular localization and functional analysis of the Arabidopsis GTPase RabE.

Journal Article Plant physiology · April 2009 Membrane trafficking plays a fundamental role in eukaryotic cell biology. Of the numerous known or predicted protein components of the plant cell trafficking system, only a relatively small subset have been characterized with respect to their biological ro ... Full text Cite

Mitogen-activated protein kinases 3 and 6 are required for full priming of stress responses in Arabidopsis thaliana.

Journal Article The Plant cell · March 2009 In plants and animals, induced resistance (IR) to biotic and abiotic stress is associated with priming of cells for faster and stronger activation of defense responses. It has been hypothesized that cell priming involves accumulation of latent signaling co ... Full text Cite

The plant innate immunity response in stomatal guard cells invokes G-protein-dependent ion channel regulation.

Journal Article The Plant journal : for cell and molecular biology · December 2008 Stomata in the epidermis of terrestrial plants are important for CO2 absorption and transpirational water loss, and are also potential points of entry for pathogens. Stomatal opening and closure are controlled by distinct mechanisms. Arabidopsis stomata ha ... Full text Cite

A critical role of two positively charged amino acids in the Jas motif of Arabidopsis JAZ proteins in mediating coronatine- and jasmonoyl isoleucine-dependent interactions with the COI1 F-box protein.

Journal Article The Plant journal : for cell and molecular biology · September 2008 SummaryCoronatine is an important virulence factor produced by several pathovars of the bacterial pathogen Pseudomonas syringae. The structure of coronatine is similar to that of a class of plant hormones called jasmonates (JAs). An important step ... Full text Cite

Suppression of the microRNA pathway by bacterial effector proteins.

Journal Article Science (New York, N.Y.) · August 2008 Plants and animals sense pathogen-associated molecular patterns (PAMPs) and in turn differentially regulate a subset of microRNAs (miRNAs). However, the extent to which the miRNA pathway contributes to innate immunity remains unknown. Here, we show that mi ... Full text Cite

COI1 is a critical component of a receptor for jasmonate and the bacterial virulence factor coronatine.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · May 2008 Jasmonate (JA) is a lipid-derived hormone that regulates diverse aspects of plant immunity and development. An amino acid-conjugated form of JA, jasmonoyl-isoleucine (JA-Ile), stimulates binding of the F-box protein coronatine-insensitive 1 (COI1) to, and ... Full text Cite

Expression of the type III secretion chaperone protein DspF of Erwinia amylovora in apple increases resistance to fire blight

Conference Acta Horticulturae · January 1, 2008 Erwinia amylovora causes fire blight of apple, pear and other rosaceous plants and elicits plant defense responses in non-host plants. Required for these interactions are the clustered bacterial hrp genes, which encode a large set of proteins broadly conse ... Full text Cite

Translocation and chaperone interaction of the Erwinia amylovora secreted effector DspE

Conference Acta Horticulturae · January 1, 2008 Pathogenesis of Erwinia amylovora, the causal agent of fire blight, requires injection of the effector protein DspE into host cells via the type III secretion system (T3SS). Secretion is facilitated by the chaperone protein DspF, but the portion of DspE re ... Full text Cite

Role of stomata in plant innate immunity and foliar bacterial diseases.

Book · January 2008 Pathogen entry into host tissue is a critical first step in causing infection. For foliar bacterial plant pathogens, natural surface openings, such as stomata, are important entry sites. Historically, these surface openings have been considered as passive ... Full text Cite

Overexpression of the apple MpNPR1 gene confers increased disease resistance in Malus x domestica.

Journal Article Molecular plant-microbe interactions : MPMI · December 2007 The NPR1 gene plays a pivotal role in systemic acquired resistance in plants. Its overexpression in Arabidopsis and rice results in increased disease resistance and elevated expression of pathogenesis-related (PR) genes. An NPR1 homolog, MpNPR1-1, was clon ... Full text Cite

Pathogen virulence factors as molecular probes of basic plant cellular functions.

Journal Article Current opinion in plant biology · December 2007 To successfully colonize plants, pathogens have evolved a myriad of virulence factors that allow them to manipulate host cellular pathways in order to gain entry into, multiply and move within, and eventually exit the host for a new infection cycle. In the ... Full text Cite

The Pseudomonas syringae type III effector tyrosine phosphatase HopAO1 suppresses innate immunity in Arabidopsis thaliana.

Journal Article The Plant journal : for cell and molecular biology · November 2007 The bacterial pathogen Pseudomonas syringae pv. tomato (Pst) strain DC3000 infects tomato and Arabidopsis plants, and is a model for studying the molecular basis of bacterial disease. Pst DC3000 secretes a battery of largely uncharacterized effector protei ... Full text Cite

JAZ repressor proteins are targets of the SCF(COI1) complex during jasmonate signalling.

Journal Article Nature · August 2007 Jasmonate and related signalling compounds have a crucial role in both host immunity and development in plants, but the molecular details of the signalling mechanism are poorly understood. Here we identify members of the jasmonate ZIM-domain (JAZ) protein ... Full text Cite

Role of plant stomata in bacterial invasion.

Journal Article Cellular microbiology · July 2007 Stomata are microscopic pores in the epidermis of the aerial parts of terrestrial plants. These pores are essential for photosynthesis, as they allow CO(2) to diffuse into the plant. The size of the stomatal pore changes in response to environmental condit ... Full text Cite

Strategies for obtaining fire blight resistance in apple by rDNA technology

Conference Acta Horticulturae · January 1, 2007 The fire blight disease of apple (Malus x domestica), caused by the bacterium Erwinia amylovora, is difficult to manage on most cultivars because of their susceptibility and the paucity of effective control materials. Because of apple's heterozygosity, sel ... Full text Cite

Plant stomata function in innate immunity against bacterial invasion.

Journal Article Cell · September 2006 Microbial entry into host tissue is a critical first step in causing infection in animals and plants. In plants, it has been assumed that microscopic surface openings, such as stomata, serve as passive ports of bacterial entry during infection. Surprisingl ... Full text Cite

Biotic interactions: towards a unifying and balanced view.

Journal Article Current opinion in plant biology · August 2006 Full text Cite

A bacterial virulence protein suppresses host innate immunity to cause plant disease.

Journal Article Science (New York, N.Y.) · July 2006 Plants have evolved a powerful immune system to defend against infection by most microbial organisms. However, successful pathogens, such as Pseudomonas syringae, have developed countermeasures and inject virulence proteins into the host plant cell to supp ... Full text Cite

The Erwinia amylovora avrRpt2EA gene contributes to virulence on pear and AvrRpt2EA is recognized by Arabidopsis RPS2 when expressed in pseudomonas syringae.

Journal Article Molecular plant-microbe interactions : MPMI · June 2006 The enterobacterium Erwinia amylovora is a devastating plant pathogen causing necrotrophic fire blight disease of apple, pear, and other rosaceous plants. In an attempt to identify genes induced during infection of host plants, we identified and cloned a p ... Full text Cite

Genome-wide transcriptional analysis of the Arabidopsis thaliana interaction with the plant pathogen Pseudomonas syringae pv. tomato DC3000 and the human pathogen Escherichia coli O157:H7.

Journal Article The Plant journal : for cell and molecular biology · April 2006 Pseudomonas syringae pv. tomato DC3000 (Pst) is a virulent pathogen that causes disease on tomato and Arabidopsis. The type III secretion system (TTSS) plays a key role in pathogenesis by translocating virulence effectors from the bacteria into the plant h ... Full text Cite

Transgenic apple lines over-expressing the apple gene MpNPR1 have increased resistance to fire blight

Journal Article Acta Horticulturae · January 1, 2006 The NPR1 gene is thought to be pivotal in the defense cascade caused by systemic acquired resistance and by R gene resistance in plants. Its over-expression in Arabidopsis and rice has resulted in increased disease resistance and elevated PR-gene expressio ... Full text Cite

Suppression of host defense in compatible plant-Pseudomonas syringae interactions.

Journal Article Current opinion in plant biology · August 2005 Despite impressive advances in the study of plant resistance to pathogens, little is known about the molecular basis of plant susceptibility to virulent pathogens. Recent progress in susceptible plant-Pseudomonas syringae interactions has provided a glimps ... Full text Cite

Use of dominant-negative HrpA mutants to dissect Hrp pilus assembly and type III secretion in Pseudomonas syringae pv. tomato.

Journal Article The Journal of biological chemistry · June 2005 The Hrp pilus plays an essential role in the long-distance type III translocation of effector proteins from bacteria into plant cells. HrpA is the structural subunit of the Hrp pilus in Pseudomonas syringae pv. tomato (Pst) DC3000. Little is known about th ... Full text Cite

Powerful screens for bacterial virulence proteins.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · March 2005 Full text Cite

Type III protein secretion mechanism in mammalian and plant pathogens.

Journal Article Biochimica et biophysica acta · November 2004 The type III protein secretion system (TTSS) is a complex organelle in the envelope of many Gram-negative bacteria; it delivers potentially hundreds of structurally diverse bacterial virulence proteins into plant and animal cells to modulate host cellular ... Full text Cite

Regulation of plant arginase by wounding, jasmonate, and the phytotoxin coronatine.

Journal Article The Journal of biological chemistry · October 2004 In mammalian cells, induced expression of arginase in response to wound trauma and pathogen infection plays an important role in regulating the metabolism of L-arginine to either polyamines or nitric oxide (NO). In higher plants, which also utilize arginin ... Full text Cite

A family of conserved bacterial effectors inhibits salicylic acid-mediated basal immunity and promotes disease necrosis in plants.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · June 2004 Salicylic acid (SA)-mediated host immunity plays a central role in combating microbial pathogens in plants. Inactivation of SA-mediated immunity, therefore, would be a critical step in the evolution of a successful plant pathogen. It is known that mutation ... Full text Cite

Over-expression of the apple gene MpNPR1 causes increased disease resistance in Malus x domestica

Conference Acta Horticulturae · January 1, 2004 The NPR1 gene is thought to be pivotal in the defense cascade caused by systemic acquired resistance and by R gene resistance in plants. Its over-expression in Arabidopsis and rice has resulted in increased disease resistance and elevated PR-gene expressio ... Full text Cite

Virulence systems of Pseudomonas syringae pv. tomato promote bacterial speck disease in tomato by targeting the jasmonate signaling pathway.

Journal Article The Plant journal : for cell and molecular biology · November 2003 Pseudomonas syringae pv. tomato strain DC3000 (Pst DC3000) causes bacterial speck disease on tomato. The pathogenicity of Pst DC3000 depends on both the type III secretion system that delivers virulence effector proteins into host cells and the phytotoxin ... Full text Cite

Pseudomonas syringae pv. tomato DC3000 HopPtoM (CEL ORF3) is important for lesion formation but not growth in tomato and is secreted and translocated by the Hrp type III secretion system in a chaperone-dependent manner.

Journal Article Molecular microbiology · September 2003 Pseudomonas syringae pv. tomato DC3000 is a pathogen of tomato and Arabidopsis that injects virulence effector proteins into host cells via a type III secretion system (TTSS). TTSS-deficient mutants have a Hrp- phenotype, that is, they cannot elicit the hy ... Full text Cite

Development of fire blight resistant apple cultivars by genetic engineering

Conference Acta Horticulturae · August 31, 2003 To prove the concept that genetic engineering could be used to create fire blight (FB) resistant strains of apple cultivars, 'Royal Gala' ('RG') was transformed using Agrobacterium with genes for several heterologous lytic proteins (LP), driven by constitu ... Full text Cite

A Pseudomonas syringae type III effector suppresses cell wall-based extracellular defense in susceptible Arabidopsis plants.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 2003 Bacterial effector proteins secreted through the type III secretion system (TTSS) play a crucial role in causing plant and human diseases. Although the ability of type III effectors to trigger defense responses in resistant plants is well understood, the d ... Full text Cite

Type III protein secretion in Pseudomonas syringae.

Journal Article Microbes and infection · April 2003 The type III secretion system is an essential virulence system used by many Gram-negative bacterial pathogens to deliver effector proteins into host cells. This review summarizes recent advancements in the understanding of the type III secretion system of ... Full text Cite

Interplay of the Arabidopsis nonhost resistance gene NHO1 with bacterial virulence.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · March 2003 It is poorly understood why a particular plant species is resistant to the vast majority of potential pathogens that infect other plant species, a phenomenon referred to as "nonhost" resistance. Here, we show that Arabidopsis NHO1, encoding a glycerol kina ... Full text Cite

The Hrp pilus: learning from flagella.

Journal Article Current opinion in microbiology · February 2003 Plant pathogenic bacteria deliver avirulence and virulence effector proteins into plant cells via the hrp-gene-encoded type III secretion system. A key component of this secretion system is a surface appendage called the Hrp pilus. Recent results suggest t ... Full text Cite

Identification of novel hrp-regulated genes through functional genomic analysis of the Pseudomonas syringae pv. tomato DC3000 genome.

Journal Article Molecular microbiology · September 2002 Pseudomonas syringae pv. tomato (Pst) strain DC3000 infects the model plants Arabidopsis thaliana and tomato, causing disease symptoms characterized by necrotic lesions surrounded by chlorosis. One mechanism used by Pst DC3000 to infect host plants is the ... Full text Cite

Effect of Treating Apple Trees with Acibenzolar-S-Methyl on Fire Blight and Expression of Pathogenesis-Related Protein Genes.

Journal Article Plant disease · July 2002 Acibenzolar-S-methyl (ASM, Actigard 50 WG), a synthetic inducer of systemic acquired resistance (SAR) and pathogenesis-related (PR) proteins, was evaluated for the control of fire blight on apple trees in the field and for PR protein gene expression in app ... Full text Cite

DNA sequence and genetic characterization of plasmid pFQ11 from Frankia alni strain CpI1.

Journal Article FEMS microbiology letters · January 2002 An 8551-bp plasmid, pFQ11, from Frankia alni strain CpI1 was sequenced. Its sequence was found to be very similar to that presented for pFQ31 from strain ArI3. Six potential protein-encoding open reading frames (ORFs) were identified, and transcriptional a ... Full text Cite

Secretion of Hrp and Dsp proteins via the Hrp pilus during type III secretion in Erwinia amylovora

Conference Acta Horticulturae · January 1, 2002 The pathogenicity of Erwinia amylovora is controlled in part by the type III protein secretion system, which is encoded by hrp genes. When grown in medium that induces hrp gene expression, E. amylovora strain Ea110 assembled pili. Immunogold labeling and g ... Full text Cite

Role of the Hrp pilus in type III protein secretion in Pseudomonas syringae.

Journal Article Science (New York, N.Y.) · December 2001 Bacterial surface appendages called pili and needle-like filaments are associated with protein and/or DNA transfer to recipient plant, human, or bacterial cells during pathogenesis or conjugation. Although it has long been suspected that pili function as a ... Full text Cite

Visualization of secreted Hrp and Avr proteins along the Hrp pilus during type III secretion in Erwinia amylovora and Pseudomonas syringae.

Journal Article Molecular microbiology · June 2001 Pili are required for protein and/or DNA transfer from bacteria to recipient plant or bacterial cells, based on genetic evidence. However, it has never been shown directly that the effector proteins or DNA are localized along or inside the pili in situ. Fa ... Full text Cite

Immunogold labeling of Hrp pili of Pseudomonas syringae pv. tomato assembled in minimal medium and in planta.

Journal Article Molecular plant-microbe interactions : MPMI · February 2001 Hypersensitive reaction and pathogenicity (hrp) genes are required for Pseudomonas syringae pv. tomato (Pst) DC3000 to cause disease in susceptible tomato and Arabidopsis thaliana plants and to elicit the hypersensitive response in resistant plants. The hr ... Full text Cite

Expression of a functional antizearalenone single-chain Fv antibody in transgenic Arabidopsis plants.

Journal Article Applied and environmental microbiology · August 2000 The efficacy of cloning a recombinant mycotoxin antibody in plants was tested using Arabidopsis as a model. An antizearalenone single-chain Fv (scFv) DNA fragment was first cloned in the newly constructed phage display vector (pEY.5) and then recloned in t ... Full text Cite

Conversion of compatible plant-pathogen interactions into incompatible interactions by expression of the Pseudomonas syringae pv. syringae 61 hrmA gene in transgenic tobacco plants.

Journal Article The Plant journal : for cell and molecular biology · July 2000 The hrmA gene from Pseudomonas syringae pv. syringae has previously been shown to confer avirulence on the virulent bacterium P. syringae pv. tabaci in all examined tobacco cultivars. We expressed this gene in tobacco plants under the control of the tobacc ... Full text Cite

The gene coding for the Hrp pilus structural protein is required for type III secretion of Hrp and Avr proteins in Pseudomonas syringae pv. tomato.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · February 2000 Bacterial surface appendages called pili often are associated with DNA and/or protein transfer between cells. The exact function of pili in the transfer process is not understood and is a matter of considerable debate. The Hrp pilus is assembled by the Hrp ... Full text Cite

A gene family in Arabidopsis thaliana with sequence similarity to NDR1 and HIN1

Journal Article Plant Physiology and Biochemistry · January 1, 2000 The NDR1 gene of Arabidopsis thaliana is required for resistance to certain pathogens. Tobacco NDR1 and HIN1 share sequence similarity and are inducible in response to pathogen infection. In this study, 29 open reading frames were identified in Arabidopsis ... Full text Cite

The hrp pilus and extracellular proteins of erwinia amylovora

Conference Acta Horticulturae · January 1, 1999 Erwinia amylovora is the causal agent of fire blight on apple and pear trees. It elicits a hypersensitive response (HR) on nonhost plant species, such as tobacco. The long-term goal of this project is to produce fire-blight-resistant apple plants expressin ... Full text Cite

The HHR pilus and extracellular proteins of Erwinia amylovora

Conference PROCEEDINGS OF THE EIGHTH INTERNATIONAL WORKSHOP ON FIRE BLIGHT · 1999 Cite

The Pseudomonas syringae pv. tomato HrpW protein has domains similar to harpins and pectate lyases and can elicit the plant hypersensitive response and bind to pectate.

Journal Article Journal of bacteriology · October 1998 The host-specific plant pathogen Pseudomonas syringae elicits the hypersensitive response (HR) in nonhost plants and secretes the HrpZ harpin in culture via the Hrp (type III) secretion system. Previous genetic evidence suggested the existence of another h ... Full text Cite

Type III protein secretion systems in plant and animal pathogenic bacteria.

Journal Article Annual review of phytopathology · January 1998 Among many interesting and sophisticated mechanisms used by bacterial pathogens to subvert eukaryotic hosts is a class of specialized protein secretion systems (known as type III protein secretion systems) that deliver bacterial virulence proteins directly ... Full text Cite

Hrp-controlled interkingdom protein transport: learning from flagellar assembly?

Journal Article Trends in microbiology · December 1997 Plant pathogenic bacteria appear to deliver avirulence and virulence proteins through the cell wall and into the host cells via an Hrp (hypersensitive reaction and pathogenicity)-encoded type III secretion system. Recent results suggest that there is a sim ... Full text Cite

Hrp pilus: an hrp-dependent bacterial surface appendage produced by Pseudomonas syringae pv. tomato DC3000.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · April 1997 Hypersensitive response and pathogenicity (hrp) genes control the ability of major groups of plant pathogenic bacteria to elicit the hypersensitive response (HR) in resistant plants and to cause disease in susceptible plants. A number of Hrp proteins share ... Full text Cite

Elicitation of Plant Hypersensitive Response by Bacteria.

Journal Article Plant physiology · November 1996 Full text Cite

The Pseudomonas syringae Hrp regulation and secretion system controls the production and secretion of multiple extracellular proteins.

Journal Article Journal of bacteriology · November 1996 Pseudomonas syringae pv. tomato DC3000 produces seven to eight major extracellular proteins (EXPs) in a minimal medium inducing hrp genes. Using a polyclonal antibody against DC3000 EXPs, we have determined that the production and secretion of five EXPs (E ... Full text Cite

hrp gene-dependent induction of hin1: a plant gene activated rapidly by both harpins and the avrPto gene-mediated signal.

Journal Article The Plant journal : for cell and molecular biology · October 1996 Two classes of bacterial genes are involved in the elicitation of the plant hypersensitive response (HR) in resistant plants: hrp genes and avr genes. hrp genes have been shown to be involved in the production and secretion of a new class of bacterial viru ... Full text Cite

Expression of the Pseudomonas syringae avirulence protein AvrB in plant cells alleviates its dependence on the hypersensitive response and pathogenicity (Hrp) secretion system in eliciting genotype-specific hypersensitive cell death.

Journal Article The Plant cell · July 1996 The nonpathogenic bacteria Pseudomonas fluorescens and Escherichia coli can elicit a genotype-specific hypersensitive response (HR) in plants if they express both the HR and pathogenesis (Hrp) protein secretion system and the HrpZ harpin from P. syringae p ... Full text Cite

Induction of systemic acquired resistance in cucumber by Pseudomonas syringae pv. syringae 61 HrpZPss protein

Journal Article Plant Journal · January 1, 1996 Systemic acquired resistance (SAR) is an inducible plant defense response and is effective against a broad spectrum of pathogens. Biological induction of SAR usually follows plant cell death resulting from the plant hypersensitive response (HR) elicited by ... Full text Cite

The interaction of harpinPss, with plant cell walls

Journal Article Molecular Plant-Microbe Interactions · January 1, 1996 Erwinia amylovora and Pseudomonas syringae pv. syringae produce elicitors of the hypersensitive reaction (HR), harphiEa and harpinPss, respectively. HarpinEa causes K+ efflux and extracellular alkalinization in suspension-cultured cells of tobacco. These r ... Full text Cite

The HrpZ proteins of Pseudomonas syringae pvs. syringae, glycinea, and tomato are encoded by an operon containing Yersinia ysc homologs and elicit the hypersensitive response in tomato but not soybean.

Journal Article Molecular plant-microbe interactions : MPMI · September 1995 The Pseudomonas syringae pathovars are composed of host-specific plant pathogens that characteristically elicit the defense-associated hypersensitive response (HR) in nonhost plants. P. s. pv. syringae 61 secretes an HR elicitor, harpinPss (HrpZPss), in a ... Full text Cite

Hypersensitive response elicited by Erwinia amylovora harpin requires active plant metabolism

Journal Article Molecular Plant-Microbe Interactions · January 1, 1994 Full text Cite

Pseudomonas syringae pv. syringae harpinPss: a protein that is secreted via the Hrp pathway and elicits the hypersensitive response in plants.

Journal Article Cell · July 1993 The ability of P. syringae to elicit the hypersensitive response in nonhost plants or pathogenesis in hosts is controlled by hrp genes. The P. syringae pv. syringae 61 hrpZ gene encodes harpinPss, a 34.7 kd extracellular protein that elicits hypersensitive ... Full text Cite

The Pseudomonas syringae pv. syringae 61 hrpH product, an envelope protein required for elicitation of the hypersensitive response in plants.

Journal Article Journal of bacteriology · November 1992 Pseudomonas syringae pv. syringae 61 contains a 25-kb cluster of hrp genes that are required for elicitation of the hypersensitive response (HR) in tobacco. TnphoA mutagenesis of cosmid pHIR11, which contains the hrp cluster, revealed two genes encoding ex ... Full text Cite

Harpin, elicitor of the hypersensitive response produced by the plant pathogen Erwinia amylovora.

Journal Article Science (New York, N.Y.) · July 1992 A proteinaceous elicitor of the plant defense reaction known as the hypersensitive response was isolated from Erwinia amylovora, the bacterium that causes fire blight of pear, apple, and other rosaceous plants. The elicitor, named harpin, is an acidic, hea ... Full text Cite

Extracellular secretion of pectate lyase by the Erwinia chrysanthemi out pathway is dependent upon Sec-mediated export across the inner membrane.

Journal Article Journal of bacteriology · July 1991 The plant pathogenic enterobacterium Erwinia chrysanthemi EC16 secretes several extracellular, plant cell wall-degrading enzymes, including pectate lyase isozyme PelE. Secretion kinetics of 35S-labeled PelE indicated that the precursor of PelE was rapidly ... Full text Cite

Cloned Erwinia chrysanthemi out genes enable Escherichia coli to selectively secrete a diverse family of heterologous proteins to its milieu.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · February 1991 The out genes of the enterobacterial plant pathogen Erwinia chrysanthemi are responsible for the efficient extracellular secretion of multiple plant cell wall-degrading enzymes, including four isozymes of pectate lyase, exo-poly-alpha-D-galacturonosidase, ... Full text Cite

Molecular cloning of the structural gene for exopolygalacturonate lyase from Erwinia chrysanthemi EC16 and characterization of the enzyme product.

Journal Article Journal of bacteriology · December 1990 The ability of Erwinia chrysanthemi to cause soft-rot diseases involving tissue maceration in many plants has been linked to the production of endo-pectate lyase E. chrysanthemi EC16 mutant UM1005, however, contains deletions in the pel genes that encode t ... Full text Cite

Molecular cloning, nucleotide sequence, and marker exchange mutagenesis of the exo-poly-alpha-D-galacturonosidase-encoding pehX gene of Erwinia chrysanthemi EC16.

Journal Article Journal of bacteriology · September 1990 The pehX gene encoding extracellular exo-poly-alpha-D-galacturonosidase (exoPG; EC 3.2.1.82) was isolated from a genomic library of the pectate lyase-deficient Erwinia chrysanthemi mutant UM1005 (a Nalr Kanr delta pelABCE derivative of EC16) by immunoscree ... Full text Cite