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1.
Int J Mol Sci ; 25(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38397062

RESUMO

The ubiquitin/26S proteasome system is a crucial regulatory mechanism that governs various cellular processes in plants, including signal transduction, transcriptional regulation, and responses to biotic and abiotic stressors. Our study shows that the RING-H2-type E3 ubiquitin ligase, Arabidopsis Tóxicos en Levadura 2 (ATL2), is involved in response to fungal pathogen infection. Under normal growth conditions, the expression of the ATL2 gene is low, but it is rapidly and significantly induced by exogenous chitin. Additionally, ATL2 protein stability is markedly increased via chitin treatment, and its degradation is prolonged when 26S proteasomal function is inhibited. We found that an atl2 null mutant exhibited higher susceptibility to Alternaria brassicicola, while plants overexpressing ATL2 displayed increased resistance. We also observed that the hyphae of A. brassicicola were strongly stained with trypan blue staining, and the expression of A. brassicicola Cutinase A (AbCutA) was dramatically increased in atl2. In contrast, the hyphae were weakly stained, and AbCutA expression was significantly reduced in ATL2-overexpressing plants. Using bioinformatics, live-cell confocal imaging, and cell fractionation analysis, we revealed that ATL2 is localized to the plasma membrane. Further, it is demonstrated that the ATL2 protein possesses E3 ubiquitin ligase activity and found that cysteine 138 residue is critical for its function. Moreover, ATL2 is necessary to successfully defend against the A. brassicicola fungal pathogen. Altogether, our data suggest that ATL2 is a plasma membrane-integrated protein with RING-H2-type E3 ubiquitin ligase activity and is essential for the defense response against fungal pathogens in Arabidopsis.


Assuntos
Alternaria , Proteínas de Arabidopsis , Arabidopsis , Imunidade Vegetal , Alternaria/imunologia , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Quitina/metabolismo , Regulação da Expressão Gênica de Plantas , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
J Integr Plant Biol ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869289

RESUMO

Pathogens generate and secrete effector proteins to the host plant cells during pathogenesis to promote virulence and colonization. If the plant carries resistance (R) proteins that recognize pathogen effectors, effector-triggered immunity (ETI) is activated, resulting in a robust immune response and hypersensitive response (HR). The bipartite effector AvrRps4 from Pseudomonas syringae pv. pisi has been well studied in terms of avirulence function. In planta, AvrRps4 is processed into two parts. The C-terminal fragment of AvrRps4 (AvrRps4C) induces HR in turnip and is recognized by the paired resistance proteins AtRRS1/AtRPS4 in Arabidopsis. Here, we show that AvrRps4C targets a group of Arabidopsis WRKY, including WRKY46, WRKY53, WRKY54, and WRKY70, to induce its virulence function. Indeed, AvrRps4C suppresses the general binding and transcriptional activities of immune-positive regulator WRKY54 and WRKY54-mediated resistance. AvrRps4C interferes with WRKY54's binding activity to target gene SARD1 in vitro, suggesting WRKY54 is sequestered from the SARD1 promoter by AvrRps4C. Through the interaction of AvrRps4C with four WRKYs, AvrRps4 enhances the formation of homo-/heterotypic complexes of four WRKYs and sequesters them in the cytoplasm, thus inhibiting their function in plant immunity. Together, our results provide a detailed virulence mechanism of AvrRps4 through its C-terminus.

3.
J Integr Plant Biol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888228

RESUMO

Callose, a ß-1,3-glucan plant cell wall polymer, regulates symplasmic channel size at plasmodesmata (PD) and plays a crucial role in a variety of plant processes. However, elucidating the molecular mechanism of PD callose homeostasis is limited. We screened and identified an Arabidopsis mutant plant with excessive callose deposition at PD and found that the mutated gene was α1-COP, a member of the coat protein I (COPI) coatomer complex. We report that loss of function of α1-COP elevates the callose accumulation at PD by affecting subcellular protein localization of callose degradation enzyme PdBG2. This process is linked to the functions of ERH1, an inositol phosphoryl ceramide synthase, and glucosylceramide synthase through physical interactions with the α1-COP protein. Additionally, the loss of function of α1-COP alters the subcellular localization of ERH1 and GCS proteins, resulting in a reduction of GlcCers and GlcHCers molecules, which are key sphingolipid (SL) species for lipid raft formation. Our findings suggest that α1-COP protein, together with SL modifiers controlling lipid raft compositions, regulates the subcellular localization of GPI-anchored PDBG2 proteins, and hence the callose turnover at PD and symplasmic movement of biomolecules. Our findings provide the first key clue to link the COPI-mediated intracellular trafficking pathway to the callose-mediated intercellular signaling pathway through PD.

4.
Plant Biotechnol J ; 21(1): 17-45, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36036862

RESUMO

Plant pathogens destroy crops and cause severe yield losses, leading to an insufficient food supply to sustain the human population. Apart from relying on natural plant immune systems to combat biological agents or waiting for the appropriate evolutionary steps to occur over time, researchers are currently seeking new breakthrough methods to boost disease resistance in plants through genetic engineering. Here, we summarize the past two decades of research in disease resistance engineering against an assortment of pathogens through modifying the plant immune components (internal and external) with several biotechnological techniques. We also discuss potential strategies and provide perspectives on engineering plant immune systems for enhanced pathogen resistance and plant fitness.


Assuntos
Sistemas CRISPR-Cas , Resistência à Doença , Humanos , Resistência à Doença/genética , Engenharia Genética/métodos , Produtos Agrícolas/genética , Caminhada , Edição de Genes/métodos , Doenças das Plantas/genética , Genoma de Planta , Melhoramento Vegetal
5.
Langmuir ; 39(13): 4829-4837, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36947726

RESUMO

Hierarchical functional organic-inorganic hybrid particles for versatile control of surface wettability have attracted much attention in a wide range of applications from makeup cosmetics to anti-smudging optoelectronic devices. In this study, superhydrophobic and oleophobic organic-inorganic hybrid particles were prepared by a simple and systematic fabrication strategy using the synergistic combination of commonly available silica particles and polydimethylsiloxanes (PDMSs) with hydrophobic chain ends. Various types of PDMSs with different chain lengths and chemical structures were surface-grafted to silica microparticles through facile physical dispersion and subsequent thermal treatment to form hydrogen bonds or covalent bonds between the inorganic silica and organic PDMS polymers and thus induce a core-shell structure for the hybrid particles, which imparts superhydrophobicity and oleophobicity to the surface of silica particles. The prepared PDMS-coated silica hybrid particles with long PDMS chains exhibited a water contact angle of 151.2° and an oil contact angle of 15.2° due to the rough surface morphology and hydrophobic long-chain effects. Furthermore, the resulting organic-inorganic hybrid particles were thermally stable up to 420 °C. This controlled approach endowed the organic-inorganic hybrid particles with both superhydrophobic and oleophobic surfaces and, therefore, these particles were proven to be suitable for waterproof applications.

6.
Planta ; 256(2): 38, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35821288

RESUMO

MAIN CONCLUSION: Based on transcriptomic analysis of wild-type and mutant tomato plants, ARPC1 was found to be important for trichome formation and development and it plays a key role in terpene synthesis. Trichomes are protruding epidermal cells in plant species. They function as the first defense layer against biotic and abiotic stresses. Despite the essential role of tomato trichomes in defense against herbivores, the understanding of their development is still incomplete. Therefore, the aim of this study was to identify genes involved in trichome formation and morphology and terpene synthesis, using transcriptomic techniques. To achieve this, we examined leaf morphology and compared the expression levels of some putative genes involved in trichome formation between wild-type (WT) and hairless-3 (hl-3) tomato mutant. The hl-3 plants displayed swollen and distorted trichomes and reduced trichome density (type I and IV) and terpene synthesis compared with that of the WT plants. Gene expression analysis showed that Actin-Related Protein Component1 (ARPC1) was expressed more highly in the WT than in the hl-3 mutant, indicating its critical role in trichome morphology and density. Additionally, the expression of MYC1 and several terpene synthase genes (TPS9, 12, 20), which are involved in type VI trichome initiation and terpene synthesis, was lower in the hl-3 mutant than in the WT plants. Moreover, transformation of the hl-3 mutant with WT ARPC1 restored normal trichome structure and density, and terpene synthesis. Structural and amino acid sequence analysis showed that there was a missplicing mutation in the hl-3 mutant, which was responsible for the abnormal trichome structure and density, and impaired terpene synthesis. Overall, the findings of this study demonstrated that ARPC1 is involved in regulating trichome structure and terpene synthesis in tomato.


Assuntos
Solanum lycopersicum , Tricomas , Actinas/metabolismo , Solanum lycopersicum/metabolismo , Folhas de Planta/metabolismo , Terpenos/metabolismo , Tricomas/genética , Tricomas/metabolismo
7.
Mol Plant Microbe Interact ; 34(3): 270-278, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33147120

RESUMO

Pathogens utilize a repertoire of effectors to facilitate pathogenesis, but when the host recognizes one of them, it causes effector-triggered immunity. The Pseudomonas type III effector AvrRps4 is a bipartite effector that is processed in planta into a functional 133-amino acid N-terminus (AvrRps4-N) and 88-amino acid C-terminus (AvrRps4-C). Previous studies found AvrRps4-C to be sufficient to trigger the hypersensitive response (HR) in turnip. In contrast, our recent work found that AvrRps4-N but not AvrRps4-C triggered HR in lettuce, whereas both were required for resistance induction in Arabidopsis. Here, we initially compared AvrRps4 recognition by turnip and lettuce using transient expression. By serial truncation, we identified the central conserved region consisting of 37 amino acids as essential for AvrRps4-N recognition, whereas the putative type III secretion signal peptide or the C-terminal 13 amino acids were dispensable. Surprisingly, the conserved arginine at position 112 (R112) that is required for full-length AvrRps4 processing is also required for the recognition of AvrRps4-N by lettuce. Mutating R112 to hydrophobic leucine or negatively charged glutamate abolished the HR-inducing capacity of AvrRps4-N, while a positively charged lysine at this position resulted in a slow and weak HR. Together, our results suggest an AvrRps4-N recognition-specific role of R112 in lettuce.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Proteínas de Bactérias , Interações Hospedeiro-Patógeno , Lactuca , Pseudomonas syringae , Arabidopsis/genética , Arginina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno/genética , Lactuca/genética , Lactuca/microbiologia , Doenças das Plantas/microbiologia , Pseudomonas syringae/genética
8.
Neuroimage ; 240: 118333, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229063

RESUMO

Compassion is closely associated with prosocial behavior. Although there is growing interest in developing strategies that cultivate compassion, most available strategies rely on effortful reflective processes. Furthermore, few studies have investigated neurocognitive mechanisms underlying compassion-dependent improvement of prosocial responses. We devised a novel implicit compassion promotion task that operates based on association learning and examined its prosocial effects in two independent experiments. In Experiment 1, healthy adults were assigned to either the compassion or control group. For the intervention task, the compassion group completed word fragments that were consistently related to compassionate responses toward others; in contrast, the control group completed word fragments related to emotionally neutral responses toward others. Following the intervention task, we measured attentional biases to fearful, sad, and happy faces. Prosocial responses were assessed using two measures of helping: the pen-drop test and the helping intentions rating test. In Experiment 2, independent groups of healthy adults completed the same intervention tasks used in Experiment 1. Inside a functional MRI scanner, participants rated empathic care and distress based on either distressful or neutral video clips. Outside the scanner, we assessed the degree of helping intentions toward the victims depicted in the distressful clips. The results of Experiment 1 showed that the compassion promotion task reduced attentional vigilance to fearful faces, which in turn mediated a compassion promotion task-dependent increase in helping intentions. In Experiment 2, relative to the control group, the compassion group showed reduced empathic distress and increased activity in the medial orbitofrontal cortex in response to others' suffering. Furthermore, increased functional connectivity of the medial orbitofrontal and inferior parietal cortex, predicted by reduced empathic distress, explained the increase in helping intentions. These results suggest the potential of implicit compassion promotion intervention to modulate compassion-related and prosocial responses as well as highlight the brain activation and connectivity related to these responses, contributing to our understanding of the neurocognitive mechanisms underlying compassion-dependent prosocial improvement.


Assuntos
Altruísmo , Viés de Atenção/fisiologia , Cognição/fisiologia , Empatia/fisiologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Lobo Parietal/diagnóstico por imagem , Estimulação Luminosa/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
9.
Plant Cell Rep ; 40(6): 999-1011, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33074435

RESUMO

KEY MESSAGE: CRISPR/Cas9-based multiplexed editing of SlHyPRP1 resulted in precise deletions of its functional motif(s), thereby resulting in salt stress-tolerant events in cultivated tomato. Crop genetic improvement to address environmental stresses for sustainable food production has been in high demand, especially given the current situation of global climate changes and reduction of the global food production rate/population rate. Recently, the emerging clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas)-based targeted mutagenesis has provided a revolutionary approach to crop improvement. The major application of CRISPR/Cas in plant genome editing has been the generation of indel mutations via error-prone nonhomologous end joining (NHEJ) repair of DNA DSBs. In this study, we examined the power of the CRISPR/Cas9-based novel approach in the precise manipulation of protein domains of tomato hybrid proline-rich protein 1 (HyPRP1), which is a negative regulator of salt stress responses. We revealed that the precise elimination of SlHyPRP1 negative-response domain(s) led to high salinity tolerance at the germination and vegetative stages in our experimental conditions. CRISPR/Cas9-based domain editing may be an efficient tool to engineer multidomain proteins of important food crops to cope with global climate changes for sustainable agriculture and future food security.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Proteínas de Plantas/genética , Estresse Salino/fisiologia , Solanum lycopersicum/genética , Agrobacterium tumefaciens/genética , Alelos , Clonagem Molecular , Produtos Agrícolas/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Germinação/genética , Solanum lycopersicum/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Domínios Proteicos , RNA Guia de Cinetoplastídeos , Estresse Salino/genética , Transformação Bacteriana
10.
Adv Health Sci Educ Theory Pract ; 26(4): 1207-1227, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33877486

RESUMO

There is growing concern about a potential decline in empathy among medical students over time. Despite the importance of empathy toward patients in medicine, it remains unclear the nature of the changes in empathy among medical students. Thus, we systematically investigated affective and cognitive empathy for patients among medical students using neuroscientific approach. Nineteen medical students who completed their fifth-year medical curriculum and 23 age- and sex-matched nonmedical students participated in a functional magnetic resonance imaging study. Inside a brain scanner, all participants read empathy-eliciting scenarios while adopting either the patient or doctor perspective. Brain activation and self-reported ratings during the experience of empathy were obtained. Behavioral results indicated that all participants reported greater emotional negativity and empathic concern in association with the patient perspective condition than with the doctor perspective condition. Functional brain imaging results indicated that neural activity in the posterior superior temporal region implicated in goal-relevant attention reorienting was overall increased under the patient perspective than the doctor perspective condition. Relative to nonmedical students, medical students showed decreased activity in the temporoparietal region implicated in mentalizing under the patient perspective versus doctor perspective condition. Notably, this same region showed increased activity under the doctor versus patient condition in medical students relative to nonmedical students. This study is among the first to investigate the neural mechanisms of empathy among medical students and the current findings point to the cognitive empathy system as the locus of the primary brain differences associated with empathy toward patients.


Assuntos
Empatia , Estudantes de Medicina , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética
11.
Int J Mol Sci ; 22(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299060

RESUMO

Pseudomonas syringae-secreted HopA1 effectors are important determinants in host range expansion and increased pathogenicity. Their recent acquisitions via horizontal gene transfer in several non-pathogenic Pseudomonas strains worldwide have caused alarming increase in their virulence capabilities. In Arabidopsis thaliana, RESISTANCE TO PSEUDOMONAS SYRINGAE 6 (RPS6) gene confers effector-triggered immunity (ETI) against HopA1pss derived from P. syringae pv. syringae strain 61. Surprisingly, a closely related HopA1pst from the tomato pathovar evades immune detection. These responsive differences in planta between the two HopA1s represents a unique system to study pathogen adaptation skills and host-jumps. However, molecular understanding of HopA1's contribution to overall virulence remain undeciphered. Here, we show that immune-suppressive functions of HopA1pst are more potent than HopA1pss. In the resistance-compromised ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) null-mutant, transcriptomic changes associated with HopA1pss-elicited ETI are still induced and carry resemblance to PAMP-triggered immunity (PTI) signatures. Enrichment of HopA1pss interactome identifies proteins with regulatory roles in post-transcriptional and translational processes. With our demonstration here that both HopA1 suppress reporter-gene translations in vitro imply that the above effector-associations with plant target carry inhibitory consequences. Overall, with our results here we unravel possible virulence role(s) of HopA1 in suppressing PTI and provide newer insights into its detection in resistant plants.


Assuntos
Arabidopsis/imunologia , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno , Degradação do RNAm Mediada por Códon sem Sentido , Doenças das Plantas/imunologia , Imunidade Vegetal , Pseudomonas syringae/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas de Bactérias/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Virulência
12.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946790

RESUMO

Plants rely on multiple immune systems to protect themselves from pathogens. When pattern-triggered immunity (PTI)-the first layer of the immune response-is no longer effective as a result of pathogenic effectors, effector-triggered immunity (ETI) often provides resistance. In ETI, host plants directly or indirectly perceive pathogen effectors via resistance proteins and launch a more robust and rapid defense response. Resistance proteins are typically found in the form of nucleotide-binding and leucine-rich-repeat-containing receptors (NLRs). Upon effector recognition, an NLR undergoes structural change and associates with other NLRs. The dimerization or oligomerization of NLRs signals to downstream components, activates "helper" NLRs, and culminates in the ETI response. Originally, PTI was thought to contribute little to ETI. However, most recent studies revealed crosstalk and cooperation between ETI and PTI. Here, we summarize recent advancements in our understanding of the ETI response and its components, as well as how these components cooperate in the innate immune signaling pathways. Based on up-to-date accumulated knowledge, this review provides our current perspective of potential engineering strategies for crop protection.


Assuntos
Imunidade Vegetal , Resistência à Doença/genética , Resistência à Doença/imunologia , Evolução Molecular , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/genética , Modelos Imunológicos , Proteínas NLR/genética , Proteínas NLR/imunologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia
13.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34204013

RESUMO

Plant immunity is mediated in large part by specific interactions between a host resistance protein and a pathogen effector protein, named effector-triggered immunity (ETI). ETI needs to be tightly controlled both positively and negatively to enable normal plant growth because constitutively activated defense responses are detrimental to the host. In previous work, we reported that mutations in SUPPRESSOR OF rps4-RLD1 (SRFR1), identified in a suppressor screen, reactivated EDS1-dependent ETI to Pseudomonas syringae pv. tomato (Pto) DC3000. Besides, mutations in SRFR1 boosted defense responses to the generalist chewing insect Spodoptera exigua and the sugar beet cyst nematode Heterodera schachtii. Here, we show that mutations in SRFR1 enhance susceptibility to the fungal necrotrophs Fusarium oxysporum f. sp. lycopersici (FOL) and Botrytis cinerea in Arabidopsis. To translate knowledge obtained in AtSRFR1 research to crops, we generated SlSRFR1 alleles in tomato using a CRISPR/Cas9 system. Interestingly, slsrfr1 mutants increased expression of SA-pathway defense genes and enhanced resistance to Pto DC3000. In contrast, slsrfr1 mutants elevated susceptibility to FOL. Together, these data suggest that SRFR1 is functionally conserved in both Arabidopsis and tomato and functions antagonistically as a negative regulator to (hemi-) biotrophic pathogens and a positive regulator to necrotrophic pathogens.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/microbiologia , Botrytis/fisiologia , Resistência à Doença/imunologia , Fusarium/fisiologia , Imunidade Vegetal , Alelos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência de Bases , Sistemas CRISPR-Cas/genética , Resistência à Doença/genética , Edição de Genes , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Vetores Genéticos/metabolismo , Solanum lycopersicum/genética , Mutação/genética , Imunidade Vegetal/genética , Plasmídeos/genética
14.
PLoS Pathog ; 14(3): e1006984, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29601603

RESUMO

Bacterial effector proteins secreted into host plant cells manipulate those cells to the benefit of the pathogen, but effector-triggered immunity (ETI) occurs when effectors are recognized by host resistance proteins. The RPS4/RRS1 pair recognizes the Pseudomonas syringae pv. pisi effector AvrRps4. AvrRps4 is processed in planta into AvrRps4N (133 amino acids), homologous to the N-termini of other effectors including the native P. syringae pv. tomato strain DC3000 effector HopK1, and AvrRps4C (88 amino acids). Previous data suggested that AvrRps4C alone is necessary and sufficient for resistance when overexpressed in heterologous systems. We show that delivering AvrRps4C from DC3000, but not from a DC3000 hopK1- strain, triggers resistance in the Arabidopsis accession Col-0. Delivering AvrRps4C in tandem with AvrRps4N, or as a chimera with HopK1N, fully complements AvrRps4-triggered immunity. AvrRps4N in the absence of AvrRps4C enhances virulence in Col-0. In addition, AvrRps4N triggers a hypersensitive response in lettuce that is attenuated by coexpression of AvrRps4C, further supporting the role of AvrRps4N as a bona fide effector domain. Based on these results we propose that evolutionarily, fusion of AvrRps4C to AvrRps4N may have counteracted recognition of AvrRps4N, and that the plant RPS4/RRS1 resistance gene pair was selected as a countermeasure. We conclude that AvrRps4 represents an unusual chimeric effector, with recognition in Arabidopsis by RPS4/RRS1 requiring the presence of both processed effector moieties.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas de Bactérias/metabolismo , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Pseudomonas syringae/patogenicidade , Virulência , Arabidopsis/imunologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Doenças das Plantas/imunologia
15.
Adv Health Sci Educ Theory Pract ; 25(2): 283-295, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31559561

RESUMO

This study aimed to (1) evaluate the effects of an empathy education program, and (2) explore functional magnetic resonance imaging (fMRI) as a potential empathy assessment tool. An empathy enhancement program for premedical students was developed. The Korean version of the Jefferson Scale of Empathy-Student version (JSE-S) and Interpersonal Reactivity Index (K-IRI) were used to measure self-assessed changes in empathy. Clinical vignettes demonstrating empathy tasks were presented to participants undergoing fMRI, to assess regional changes in the brain. Self-reported empathy scores and brain activity signals using fMRI from before and after the program were compared. The JSE-S total and perspective taking scores significantly increased after the program. Data from the fMRI revealed noticeable differences in cognitive regions associated with empathy, namely the right superior medial frontal gyrus and left precentral gyrus. This study results support the prior evidence of positive impact of empathy education. In addition, the authors suggest that brain fMRI might be used in measuring the effectiveness of empathy education.


Assuntos
Encéfalo/diagnóstico por imagem , Educação Médica , Empatia , Imageamento por Ressonância Magnética , Psicometria , Feminino , Humanos , Masculino , Relações Médico-Paciente , República da Coreia , Autorrelato , Estudantes de Medicina/psicologia , Adulto Jovem
16.
Adv Health Sci Educ Theory Pract ; 25(2): 297, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31620964

RESUMO

Due to an unfortunate turn of events, the funding note was omitted from the original publication. The correct funding note is published here and should be treated as definitive.

17.
Plant J ; 93(4): 637-650, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29232015

RESUMO

Unlike animals, plants do not have an adaptive immune system and have instead evolved sophisticated and multi-layered innate immune mechanisms. To overcome plant immunity, pathogens secrete a diverse array of effectors into the apoplast and virtually all cellular compartments to dampen immune signaling and interfere with plant functions. Here we describe the scope of the arms race throughout the cell and summarize various strategies used by both plants and pathogens. Through studying the ongoing evolutionary battle between plants and key pathogens, we may yet uncover potential ways to achieve the ultimate goal of engineering broad-spectrum resistant crops without affecting food quality or productivity.


Assuntos
Interações Hospedeiro-Patógeno , Doenças das Plantas , Proteínas de Plantas/metabolismo , Evolução Biológica , Membrana Celular/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal , Proteínas de Plantas/imunologia , Receptores de Reconhecimento de Padrão/imunologia , Receptores de Reconhecimento de Padrão/metabolismo , Fatores de Transcrição/metabolismo
18.
J Synchrotron Radiat ; 26(Pt 4): 1127-1138, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31274436

RESUMO

PAL-XFEL utilizes a three-chicane bunch compression (3-BC) scheme (the very first of its kind in operation) for free-electron laser (FEL) operation. The addition of a third bunch compressor allows for more effective mitigation of coherent synchrotron radiation during bunch compression and an increased flexibility of system configuration. Start-to-end simulations of the effects of radiofrequency jitter on the electron beam performance show that using the 3-BC scheme leads to better performance compared with the two-chicane bunch compression scheme. Together with the high performance of the linac radiofrequency system, it enables reliable operation of PAL-XFEL with unprecedented stability in terms of arrival timing, pointing and intensity; an arrival timing jitter of better than 15 fs, a transverse position jitter of smaller than 10% of the photon beam size, and an FEL intensity jitter of smaller than 5% are consistently achieved.

19.
Foot Ankle Surg ; 25(3): 316-322, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29409176

RESUMO

BACKGROUND: We aimed to compare the clinical and radiographic outcomes of minimally invasive surgery (MIS) and distal chevron metatarsal osteotomy (DCMO) for young female patients with mild-to-moderate juvenile hallux valgus deformity. METHODS: We retrospectively reviewed the radiographs and clinical findings of young female patients with mild-to-moderate juvenile hallux valgus who underwent MIS (25 feet) or DCMO (30 feet). In 12 of 25 MIS feet, 2.0-mm bio-absorbable pins were used as an additional fixation device crossing the osteotomy site, and 1.4-mm Kirschner wires were used in the remaining 13 feet. RESULTS: Radiographic and clinical parameters preoperatively and at the final follow-up were not significantly different between the 2 groups. There were no significant differences in the increments of hallux valgus angle (HVA), distal metatarsal articular angle, medial sesamoid position, first metatarsal length, metatarsal length index, or relative second metatarsal length. Two MIS subgroups according to the additional fixation device showed no significant differences in HVA, the first to second intermetatarsal angle lateral translation ratio, or plantar offset at the final follow-up. CONCLUSIONS: MIS for young female patients with mild-to-moderate juvenile hallux valgus deformity had similar radiographic and clinical outcomes compared to DCMO. Regarding additional fixation crossing the osteotomy site, both temporary Kirschner wires and absorbable pins showed no radiographic differences in terms of correction maintenance. LEVEL OF EVIDENCE: 3.


Assuntos
Hallux Valgus/diagnóstico por imagem , Hallux Valgus/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Adolescente , Adulto , Fios Ortopédicos , Estética , Feminino , Humanos , Ossos do Metatarso/diagnóstico por imagem , Ossos do Metatarso/cirurgia , Osteotomia , Satisfação do Paciente , Estudos Retrospectivos
20.
Semin Cell Dev Biol ; 56: 150-162, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27174437

RESUMO

The plant immune system is a complex network of components that function together to sense the presence and activity of potential biotic threats, and integrate these signals into an appropriate output, namely the transcription of genes that activate an immune response that is commensurate with the perceived threat. Given the variety of biotic threats a plant must face the immune response must be plastic, but because an immune response is costly to the plant in terms of energy expenditure and development it must also be under tight control. To meet these needs transcriptional control is exercised at multiple levels. In this article we will review some of the latest developments in understanding how the plant immune response is regulated at the level of transcription. New roles are being discovered for the long-studied WRKY and TGA transcription factor families, while additional critical defense functions are being attributed to TCPs and other transcription factors. Dynamically controlling access to DNA through post-translational modification of histones is emerging as an essential component of priming, maintaining, attenuating, and repressing transcription in response to biotic stress. Unsurprisingly, the plant's transcriptional response is targeted by pathogen effectors, and in turn resistance proteins stand guard over and participate in transcriptional regulation. Together, these multiple layers lead to the observed complexity of the plant transcriptional immune response, with different transcription factors or chromatin components playing a prominent role depending on the plant-pathogen interaction being studied.


Assuntos
Regulação da Expressão Gênica de Plantas , Imunidade Inata/genética , Imunidade Vegetal/genética , Animais , Histonas/metabolismo , Humanos , Fatores de Transcrição/metabolismo
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