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1.
Plant J ; 113(2): 308-326, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36441009

RESUMO

Sorghum is an important food and feed crop globally; its production is hampered by anthracnose disease caused by the fungal pathogen Colletotrichum sublineola (Cs). Here, we report identification and characterization of ANTHRACNOSE RESISTANCE GENE 2 (ARG2) encoding a nucleotide-binding leucine-rich repeat (NLR) protein that confers race-specific resistance to Cs strains. ARG2 is one of a cluster of several NLR genes initially identified in the sorghum differential line SC328C that is resistant to some Cs strains. This cluster shows structural and copy number variations in different sorghum genotypes. Different sorghum lines carrying independent ARG2 alleles provided the genetic validation for the identity of the ARG2 gene. ARG2 expression is induced by Cs, and chitin induces ARG2 expression in resistant but not in susceptible lines. ARG2-mediated resistance is accompanied by higher expression of defense and secondary metabolite genes at early stages of infection, and anthocyanin and zeatin metabolisms are upregulated in resistant plants. Interestingly, ARG2 localizes to the plasma membrane when transiently expressed in Nicotiana benthamiana. Importantly, ARG2 plants produced higher shoot dry matter than near-isogenic lines carrying the susceptible allele suggesting an absence of an ARG2 associated growth trade-off. Furthermore, ARG2-mediated resistance is stable at a wide range of temperatures. Our observations open avenues for resistance breeding and for dissecting mechanisms of resistance.


Assuntos
Colletotrichum , Sorghum , Sorghum/genética , Variações do Número de Cópias de DNA , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Melhoramento Vegetal , Genótipo , Resistência à Doença/genética
2.
Phytopathology ; 114(8): 1940-1949, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38717940

RESUMO

Phyllachora maydis is an ascomycete foliar fungal pathogen and the causal agent of tar spot in maize. Although P. maydis is considered an economically important foliar pathogen of maize, our general knowledge of the trophic lifestyle and functional role of effector proteins from this fungal pathogen remains limited. Here, we utilized a genome-informed approach to predict the trophic lifestyle of P. maydis and functionally characterized a subset of candidate effectors from this fungal pathogen. Leveraging the most recent P. maydis genome annotation and the CATAStrophy pipeline, we show that this fungal pathogen encodes a predicted carbohydrate-active enzymes (CAZymes) repertoire consistent with that of biotrophs. To investigate fungal pathogenicity, we selected 18 candidate effector proteins that were previously shown to be expressed during primary disease development. We assessed whether these putative effectors share predicted structural similarity with other characterized fungal effectors and determined whether any suppress plant immune responses. Using AlphaFold2 and Foldseek, we showed that one candidate effector, PM02_g1115, adopts a predicted protein structure similar to that of an effector from Verticillium dahlia. Furthermore, transient expression of candidate effector-fluorescent protein fusions in Nicotiana benthamiana revealed two putative effectors, PM02_g378 and PM02_g2610, accumulated predominantly in the cytosol, and three candidate effectors, PM02_g1115, PM02_g7882, and PM02_g8240, consistently attenuated chitin-mediated reactive oxygen species production. Collectively, the results presented herein provide insights into the predicted trophic lifestyle and putative functions of effectors from P. maydis and will likely stimulate continued research to elucidate the molecular mechanisms used by P. maydis to induce tar spot.


Assuntos
Ascomicetos , Proteínas Fúngicas , Doenças das Plantas , Zea mays , Zea mays/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Ascomicetos/genética , Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genoma Fúngico/genética , Virulência , Fatores de Virulência/genética , Nicotiana/microbiologia , Nicotiana/imunologia
3.
J Toxicol Environ Health A ; 87(19): 763-772, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38922578

RESUMO

Sarcoidosis is a chronic granulomatous disease predominantly affecting the lungs and inducing significant morbidity and elevated mortality rate. The etiology of the disease is unknown but may involve exposure to an antigenic agent and subsequent inflammatory response resulting in granuloma formation. Various environmental and occupational risk factors have been suggested by previous observations, such as moldy environments, insecticides, and bird breeding. Our study investigated the association of air pollution with diagnosis of sarcoidosis using a case-control design. Penn State Health electronic medical records from 2005 to 2018 were examined for adult patients with (cases) and without (controls) an International Classification of Disease (ICD)-9 or -10 code for sarcoidosis. Patient addresses were geocoded and 24-hr residential-level air pollution concentrations were estimated using spatio-temporal models of particulate matter <2.5 µm (PM2.5), ozone, and PM2.5 elemental carbon (EC) and moving averages calculated. In total, 877 cases and 34,510 controls were identified. Logistic regression analysis did not identify significant associations between sarcoidosis incidence and air pollution exposure estimates. However, the odds ratio (OR) for EC for exposures occurring 7-10 years prior did approach statistical significance, and ORs exhibited an increasing trend for longer averaging periods. Data suggested a latency period of more than 6 years for PM2.5 and EC for reasons that are unclear. Overall, results for PM2.5 and EC suggest that long-term exposure to traffic-related air pollution may contribute to the development of sarcoidosis and emphasize the need for additional research and, if the present findings are substantiated, for public health interventions addressing air quality as well as increasing disease surveillance in areas with a large burden of PM2.5 and EC.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Material Particulado , Sarcoidose , Humanos , Poluição do Ar/efeitos adversos , Feminino , Pessoa de Meia-Idade , Masculino , Sarcoidose/epidemiologia , Sarcoidose/etiologia , Sarcoidose/induzido quimicamente , Estudos de Casos e Controles , Adulto , Material Particulado/análise , Material Particulado/efeitos adversos , Incidência , Pennsylvania/epidemiologia , Exposição Ambiental/efeitos adversos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos , Idoso
4.
Am Fam Physician ; 109(1): 19-29, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38227868

RESUMO

Sarcoidosis is a multisystem granulomatous inflammatory disease of unknown etiology that can involve any organ. Ongoing dyspnea and dry cough in a young to middle-aged adult should increase the suspicion for sarcoidosis. Symptoms can present at any age and affect any organ system; however, pulmonary sarcoidosis is the most common. Extrapulmonary manifestations often involve cardiac, neurologic, ocular, and cutaneous systems. Patients with sarcoidosis can exhibit constitutional symptoms such as fever, unintentional weight loss, and fatigue. The early recognition and diagnosis of sarcoidosis are challenging because there is no diagnostic standard for testing, initial symptoms vary, and patients may be asymptomatic. Consensus guidelines recommend a holistic approach when diagnosing sarcoidosis that focuses on clinical presentation and radiographic findings, biopsy with evidence of noncaseating granulomas, involvement of more than one organ system, and elimination of other etiologies of granulomatous disease. Corticosteroids are the initial treatment for active disease, with refractory cases often requiring immunosuppressive or biologic therapies. Transplantation can be considered for advanced and end-stage disease depending on organ involvement.


Assuntos
Sarcoidose Pulmonar , Sarcoidose , Adulto , Pessoa de Meia-Idade , Humanos , Sarcoidose/terapia , Sarcoidose/tratamento farmacológico , Sarcoidose Pulmonar/diagnóstico , Sarcoidose Pulmonar/tratamento farmacológico , Corticosteroides/uso terapêutico , Dispneia/diagnóstico , Diagnóstico Diferencial
5.
Br J Dermatol ; 188(3): 407-419, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36680309

RESUMO

BACKGROUND: Hidradenitis suppurativa (HS) is a debilitating inflammatory skin disease characterized by painful nodules, drainage and scarring in skin folds. Injectable adalimumab is the only drug approved by the US Food and Drug Administration for the treatment of HS. Although systemic Janus kinase (JAK) inhibitors show promise, serious side-effects have been reported. There are no highly effective topical treatments for HS; furthermore, the contribution of epidermal keratinocytes to the intense inflammation has largely been unexplored. OBJECTIVES: We investigated the role of keratinocytes and epidermal immune cells in HS inflammation at all Hurley stages of disease severity. We aimed to determine whether ruxolitinib can mitigate inflammation from keratinocytes and to develop a better understanding of how topical therapeutics might benefit patients with HS. METHODS: We used skin samples from 87 patients with HS (Hurley stages I-III) and 39 healthy controls to compare keratinocyte- and immune cell-driven epidermal inflammation, in addition to the response of lesional HS keratinocytes to treatment with interferon (IFN)-γ and ruxolitinib. We used haematoxylin and eosin staining, immunohistochemistry, immunoblotting and quantitative reverse-transcription polymerase chain reaction assessments in whole skin, isolated epidermis, and cultured keratinocytes from healthy controls and both nonlesional and lesional HS skin to identify and define epidermal and keratinocyte-mediated inflammation in HS and how this may be targeted by therapeutics. RESULTS: HS lesional keratinocytes autonomously secreted high levels of chemokines, such as CCL2, CCL3 and CXCL3, which recruited neutrophils, CD8 T cells, and natural killer cells to the epidermis. Keratinocytes were the dominant source of tumour necrosis factor-α and interleukin (IL)-6 in HS lesions with little to no contribution from underlying dermal immune cells. In the presence of IFN-γ, which is dependent on immune cell infiltrate in vivo, keratinocytes expressed increased levels of additional cytokines including IL-1ß, IL-12, IL-23 and IL-36γ. The JAK inhibitor ruxolitinib mitigated the expression of inflammatory cytokines and chemokines in HS lesional keratinocytes, thus providing a rationale for future study as a topical treatment for HS. CONCLUSIONS: This study demonstrates that keratinocytes actively recruit immune cells to HS epidermis and interactions between these cells drive a broad inflammatory profile in HS epidermis. Targeting epidermal inflammation in HS with novel topical formulations may be highly efficacious with reduced systemic side-effects.


Assuntos
Hidradenite Supurativa , Humanos , Hidradenite Supurativa/tratamento farmacológico , Queratinócitos/metabolismo , Epiderme/metabolismo , Inflamação , Citocinas/metabolismo
6.
J Cutan Pathol ; 50(5): 405-409, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36843055

RESUMO

Cutaneous VCL::ALK fusion spindle (ovoid) cell tumor is unique. Recently emerged RAS::MAP tyrosine kinase fusion sarcomas more commonly involve subcutis, skeletal muscle and even bone. We share our experience with a novel cutaneous VCL::ALK spindle cell tumor. An 11-year-old male presented with a back pedunculated pink-red papule thought to be a pyogenic granuloma. Biopsy histopathology revealed an epithelial collarette with pedunculated tumor extending to deep dermis/subcutis interface. The combination of spindled and epithelioid cells, an ovoid myopericytoid appearance within myxoid to collagenous stroma, low to moderate MIB1 and focal S100 protein without SOX10 immunostaining, were suggestive of a novel RAS::MAPK tyrosine kinase fusion sarcoma that is well described. ALK immunostain being positive, a next-generation sequencing comprehensive fusion panel was performed to reveal a VCL::ALK fusion. While epithelioid fibrous histiocytoma shares this fusion and similar dermal location and collarette pedunculation, this and other entities were excluded by older patient age, deeper dermal involvement, ovoid-to-spindled morphology, central pericytoid vasculature, myxoid stroma, moderate cellularity with low to moderate MIB1 expression, superficial ulceration, and focal S100 protein expression. Complete excision was performed with favorable follow-up to date. This novel VCL::ALK fusion spindle (ovoid) cell tumor of the dermis is best considered as part of the recently emerged RAS::MAP tyrosine kinase fusion sarcomas.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Masculino , Humanos , Criança , Quinase do Linfoma Anaplásico/genética , Proteínas Tirosina Quinases , Sarcoma/patologia , Proteínas S100 , Vinculina
7.
Phytopathology ; 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38079374

RESUMO

Tar spot, a disease caused by the ascomycete fungal pathogen Phyllachora maydis, is considered one of the most significant yield-limiting diseases of maize (Zea mays L.) within the United States. P. maydis may also be found in association with other fungi, forming a disease complex which is thought to result in the characteristic fish eye lesions. Understanding how P. maydis colonizes maize leaf cells is essential for developing effective disease control strategies. Here, we used histological approaches to elucidate how P. maydis infects and multiplies within susceptible maize leaves. We collected tar spot-infected maize leaf samples from four different fields in northern Indiana at three different time points during the growing season. Samples were chemically fixed and paraffin-embedded for high-resolution light and scanning electron microscopy. We observed a consistent pattern of disease progression in independent leaf samples collected across different geographical regions. Each stroma contained a central pycnidium that produced asexual spores. Perithecia with sexual spores developed in the stomatal chambers adjacent to the pycnidium, and a cap of spores formed over the stroma. P. maydis reproductive structures formed around but not within the vasculature. We observed P. maydis associated with two additional fungi, one of which is likely a member of the Paraphaeosphaeria genus; the other is an unknown fungi. Our data provide fundamental insights into how this pathogen colonizes and spreads within maize leaves. This knowledge can inform new approaches to managing tar spot, which could help mitigate the significant economic losses caused by this disease.

8.
J Drugs Dermatol ; 22(11): 7180, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943265

RESUMO

Calcinosis cutis can occur idiopathically or be associated with injury, metabolic disease, and different rheumatologic diseases such as scleroderma and dermatomyositis.


Assuntos
Calcinose Cutânea , Humanos , Calcinose Cutânea/terapia , Agulhas
9.
J Drugs Dermatol ; 22(12): e47-e48, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051834

RESUMO

Calcinosis cutis can occur idiopathically or be associated with injury, metabolic disease, and different rheumatologic diseases such as scleroderma and dermatomyositis. Calcinosis cutis is often treatment-resistant and leads to decreased quality of life and pain. Medical therapies, such as bisphosphonates, warfarin, tetracyclines, calcium channel blockers, colchicine, laser therapy and surgery, lithotripsy, and even stem cell transplantation have been used with varying success.1 Lesions of calcinosis cutis can persist even when systemic disease is adequately controlled leaving the patient with a painful reminder of their underlying disease.


Assuntos
Calcinose Cutânea , Dermatopatias , Humanos , Agulhas/efeitos adversos , Dermatopatias/diagnóstico , Dermatopatias/etiologia
10.
J Drugs Dermatol ; 22(12): 1178-1182, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051838

RESUMO

BACKGROUND: Herpes zoster increases the risk for stroke and myocardial infarction. Zoster vaccination's impact on this risk is understudied. This retrospective work sought to determine if prophylactic herpes zoster vaccination may reduce the risk of stroke, myocardial infarction, and/or mortality. METHODS: A cohort analysis utilized TriNetX, a national, federated database. In one analysis, patients who received 2 doses of recombinant zoster vaccine (RZV) were compared to adults without RZV. A 1:1 propensity-score match analysis was conducted to adjust for demographics and comorbidities in calculating adjusted relative risks (aRR) with 95% confidence intervals. First-time incidences for myocardial infarction, stroke, and mortality were assessed after 3 years. A subgroup analysis between RZV and zoster vaccine live (ZVL) was also assessed. RESULTS: Matched cohorts of 7,657 patients revealed that adults who received 2 doses of RZV were at lower risk of MI (aRR [95% CI]) = (0.73 [0.55, 0.96]) and mortality (0.7 [0.57, 0.88]) while having similar risk for stroke (0.97 [0.75, 1.26]). Further subgroup analysis also revealed a reduced risk of 3-year mortality when compared to the ZVL cohort (0.84 [0.74, 0.95]). Sample size and comorbidities included in the analysis were limited by using a large database. CONCLUSIONS: RZV reduces the 3-year risk for myocardial infarction and mortality. J Drugs Dermatol. 2023;22(12):1178-1182. doi:10.36849/JDD.7415.


Assuntos
Doenças Cardiovasculares , Vacina contra Herpes Zoster , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Vacinas Sintéticas
11.
Health Commun ; : 1-12, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37528775

RESUMO

The association of medical experts with politically left-leaning cities and states early in the COVID-19 pandemic may have exacerbated vaccine hesitancy in right-leaning states of the US. Criticism from outside experts violates rules of communication between social groups (i.e. an intergroup sensitivity effect), leading to rejection of messages promoting vaccine safety and efficacy. In two studies, we document the effects of shared geographical group membership for medical expert messages promoting vaccination. We also found evidence that satisfying conversational norms against intergroup criticism reduces message rejection. Specifically, an invitation from ingroup political elites for a doctor to speak reduced the negative effects of unshared group identity.

12.
Phytopathology ; 112(12): 2538-2548, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35815936

RESUMO

Most fungal pathogens secrete effector proteins into host cells to modulate their immune responses, thereby promoting pathogenesis and fungal growth. One such fungal pathogen is the ascomycete Phyllachora maydis, which causes tar spot disease on leaves of maize (Zea mays). Sequencing of the P. maydis genome revealed 462 putatively secreted proteins, of which 40 contain expected effector-like sequence characteristics. However, the subcellular compartments targeted by P. maydis effector candidate (PmEC) proteins remain unknown, and it will be important to prioritize them for further functional characterization. To test the hypothesis that PmECs target diverse subcellular compartments, cellular locations of super yellow fluorescent protein-tagged PmEC proteins were identified using a Nicotiana benthamiana-based heterologous expression system. Immunoblot analyses showed that most of the PmEC-fluorescent protein fusions accumulated protein in N. benthamiana, indicating that the candidate effectors could be expressed in dicot leaf cells. Laser-scanning confocal microscopy of N. benthamiana epidermal cells revealed that most of the P. maydis putative effectors localized to the nucleus and cytosol. One candidate effector, PmEC01597, localized to multiple subcellular compartments including the nucleus, nucleolus, and plasma membrane, whereas an additional putative effector, PmEC03792, preferentially labelled both the nucleus and nucleolus. Intriguingly, one candidate effector, PmEC04573, consistently localized to the stroma of chloroplasts as well as stroma-containing tubules (stromules). Collectively, these data suggest that effector candidate proteins from P. maydis target diverse cellular organelles and could thus provide valuable insights into their putative functions, as well as host processes potentially manipulated by this fungal pathogen.


Assuntos
Doenças das Plantas , Zea mays , Doenças das Plantas/microbiologia , Zea mays/microbiologia , Células Vegetais/metabolismo , Phyllachorales/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
13.
J Drugs Dermatol ; 21(11): 1252-1254, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36342728

RESUMO

Pretibial myxedema (PTM) is a rare complication of Graves' disease. It is characterized by non-pitting edema with hyperpigmented hyperkeratotic papules and plaques on bilateral lower legs. Effective treatments for patients with PTM are lacking. The etiology of PTM is unknown; however, it may be similar to the mechanism of thyroid-associated ophthalmopathy (TAO). Activated fibroblasts produce inflammatory cytokines and synthesize excessive glycosaminoglycans (GAG) that accumulate in the dermis and subcutaneous tissue. A recent, novel pathway implicates IGF-1 receptor as a mediator in this process. We present two patients with refractory PTM that improved following treatment with teprotumumab, an IGF-1 receptor inhibitor approved for use in TAO. J Drugs Dermatol. 2022;21(11):1252-1254. doi:10.36849/JDD.6854.


Assuntos
Anticorpos Monoclonais Humanizados , Doença de Graves , Mixedema , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Doença de Graves/complicações , Doença de Graves/diagnóstico , Doença de Graves/tratamento farmacológico , Mixedema/diagnóstico , Mixedema/tratamento farmacológico , Mixedema/etiologia , Receptor IGF Tipo 1
14.
Mol Plant Microbe Interact ; 34(12): 1346-1349, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34505817

RESUMO

The first of three International Society for Molecular Plant-Microbe Interactions (IS-MPMI) eSymposia was convened on 12 and 13 July 2021, with the theme "Molecular Mechanism & Structure-Zooming in on Plant Immunity". Hosted by Jian-Min Zhou (Beijing, China) and Jane Parker (Cologne, Germany), the eSymposium centered on "Top 10 Unanswered Questions in MPMI" number five: Does effector-triggered immunity (ETI) potentiate and restore pattern-triggered immunity (PTI)-or is there really a binary distinction between ETI and PTI? Since the previous International Congress of IS-MPMI in 2019, substantial progress has been made in untangling the complex signaling underlying plant immunity, including a greater understanding of the structure and function of key proteins. A clear need emerged for the MPMI community to come together virtually to share new knowledge around plant immunity. Over the course of two synchronous, half days of programming, participants from 32 countries attended two plenary sessions with engaging panel discussions and networked through interactive hours and poster breakout rooms. In this report, we summarize the concerted effort by multiple laboratories to study the molecular mechanisms underlying ETI and PTI, highlighting the essential role of plant resistosomes in the formation of calcium channels during an immune response. We conclude our report by forming new questions about how overlapping signaling mechanisms are controlled.[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
Imunidade Vegetal , Plantas , China , Doenças das Plantas , Transdução de Sinais
15.
J Drugs Dermatol ; 20(12): 1350-1351, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34898161

RESUMO

Perniosis (also known as pernio or chilblains), is a condition characterized by the development of pruritic, painful erythrocyanotic skin lesions induced by exposure to cold temperatures.2 When perniosis occurs in conjunction with clinical or laboratory features of systemic lupus erythematosus, the condition is further classified as chilblain lupus erythematosus (CHLE). CHLE is a rare condition with limited treatment options especially in refractory cases.3 Here we discuss the utility of therapeutic botulinum toxin injections in the treatment of severe, ulcerative CHLE. J Drugs Dermatol. 2021;20(12):1350-1351. doi:10.36849/JDD.6176.


Assuntos
Pérnio , Lúpus Eritematoso Sistêmico , Temperatura Baixa , Humanos
16.
Mol Plant Microbe Interact ; 33(7): 932-944, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32267815

RESUMO

The Arabidopsis resistance protein RPS5 is activated by proteolytic cleavage of the protein kinase PBS1 by the Pseudomonas syringae effector protease AvrPphB. We have previously shown that replacing seven amino acids at the cleavage site of PBS1 with a motif cleaved by the NIa protease of turnip mosaic virus (TuMV) enables RPS5 activation upon TuMV infection. However, this engineered resistance conferred a trailing necrosis phenotype indicative of a cell-death response too slow to contain the virus. We theorized this could result from a positional mismatch within the cell between PBS1TuMV, RPS5, and the NIa protease. To test this, we relocalized PBS1TuMV and RPS5 to cellular sites of NIa accumulation. These experiments revealed that relocation of RPS5 away from the plasma membrane compromised RPS5-dependent cell death in Nicotiana benthamiana, even though PBS1 was efficiently cleaved. As an alternative approach, we tested whether overexpression of plasma membrane-localized PBS1TuMV could enhance RPS5 activation by TuMV. Significantly, overexpressing the PBS1TuMV decoy protein conferred complete resistance to TuMV when delivered by either agrobacterium or by aphid transmission, showing that RPS5-mediated defense responses are effective against bacterial and viral pathogens. Lastly, we have now extended this PBS1 decoy approach to soybean by modifying a soybean PBS1 ortholog to be cleaved by the NIa protease of soybean mosaic virus (SMV). Transgenic overexpression of this soybean PBS1 decoy conferred immunity to SMV, demonstrating that we can use endogenous PBS1 proteins in crop plants to engineer economically relevant disease resistant traits.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/virologia , Resistência à Doença/genética , Glycine max/virologia , Doenças das Plantas/virologia , Potyvirus/patogenicidade , Proteínas Serina-Treonina Quinases/genética , Animais , Arabidopsis/genética , Plantas Geneticamente Modificadas/virologia , Glycine max/genética
17.
Nat Chem Biol ; 14(2): 118-125, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29200206

RESUMO

Given the importance of ubiquitin-specific protease 7 (USP7) in oncogenic pathways, identification of USP7 inhibitors has attracted considerable interest. Despite substantial efforts, however, the development of validated deubiquitinase (DUB) inhibitors that exhibit drug-like properties and a well-defined mechanism of action has proven particularly challenging. In this article, we describe the identification, optimization and detailed characterization of highly potent (IC50 < 10 nM), selective USP7 inhibitors together with their less active, enantiomeric counterparts. We also disclose, for the first time, co-crystal structures of a human DUB enzyme complexed with small-molecule inhibitors, which reveal a previously undisclosed allosteric binding site. Finally, we report the identification of cancer cell lines hypersensitive to USP7 inhibition (EC50 < 30 nM) and demonstrate equal or superior activity in these cell models compared to clinically relevant MDM2 antagonists. Overall, these findings demonstrate the tractability and druggability of DUBs, and provide important tools for additional target validation studies.


Assuntos
Antineoplásicos/química , Descoberta de Drogas , Peptidase 7 Específica de Ubiquitina/antagonistas & inibidores , Sítio Alostérico , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Cinética , Oxirredução , Inibidores de Proteases/química , Ligação Proteica , Conformação Proteica , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Especificidade por Substrato , Proteína Supressora de Tumor p53/química
18.
Mol Plant Microbe Interact ; 32(6): 760-769, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30676230

RESUMO

In Arabidopsis, recognition of the AvrPphB effector protease from Pseudomonas syringae is mediated by the disease resistance (R) protein RPS5, which is activated by AvrPphB-induced cleavage of the Arabidopsis protein kinase PBS1. The recognition specificity of RPS5 can be altered by substituting the AvrPphB cleavage site within PBS1 with cleavage sequences for other proteases, including proteases from viruses. AvrPphB also activates defense responses in soybean (Glycine max), suggesting that soybean may contain an R protein analogous to RPS5. It was unknown, however, whether this response is mediated by cleavage of a soybean PBS1-like protein. Here, we show that soybean contains three PBS1 orthologs and that their products are cleaved by AvrPphB. Further, transient expression of soybean PBS1 derivatives containing a five-alanine insertion at their AvrPphB cleavage sites activated cell death in soybean protoplasts, demonstrating that soybean likely contains an AvrPphB-specific resistance protein that is activated by a conformational change in soybean PBS1 proteins. Significantly, we show that a soybean PBS1 decoy protein modified to contain a cleavage site for the soybean mosaic virus (SMV) NIa protease triggers cell death in soybean protoplasts when cleaved by this protease, indicating that the PBS1 decoy approach will work in soybean, using endogenous PBS1 genes. Lastly, we show that activation of the AvrPphB-dependent cell death response effectively inhibits systemic spread of SMV in soybean. These data also indicate that decoy engineering may be feasible in other crop plant species that recognize AvrPphB protease activity.


Assuntos
Proteínas de Bactérias , Glycine max , Peptídeo Hidrolases , Potyvirus , Proteínas de Bactérias/metabolismo , Peptídeo Hidrolases/metabolismo , Potyvirus/enzimologia , Engenharia de Proteínas , Glycine max/metabolismo , Glycine max/virologia
19.
Mol Plant Microbe Interact ; 32(5): 550-565, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30480480

RESUMO

The Pseudomonas syringae cysteine protease AvrPphB activates the Arabidopsis resistance protein RPS5 by cleaving a second host protein, PBS1. AvrPphB induces defense responses in other plant species, but the genes and mechanisms mediating AvrPphB recognition in those species have not been defined. Here, we show that AvrPphB induces defense responses in diverse barley cultivars. We also show that barley contains two PBS1 orthologs, that their products are cleaved by AvrPphB, and that the barley AvrPphB response maps to a single locus containing a nucleotide-binding leucine-rich repeat (NLR) gene, which we termed AvrPphB Response 1 (Pbr1). Transient coexpression of PBR1 with wild-type AvrPphB but not with a protease inactive mutant triggered defense responses, indicating that PBR1 detects AvrPphB protease activity. Additionally, PBR1 coimmunoprecipitated with barley and Nicotiana benthamiana PBS1 proteins, suggesting mechanistic similarity to detection by RPS5. Lastly, we determined that wheat cultivars also recognize AvrPphB protease activity and contain two putative Pbr1 orthologs. Phylogenetic analyses showed, however, that Pbr1 is not orthologous to RPS5. Our results indicate that the ability to recognize AvrPphB evolved convergently and imply that selection to guard PBS1-like proteins occurs across species. Also, these results suggest that PBS1-based decoys may be used to engineer protease effector recognition-based resistance in barley and wheat.


Assuntos
Arabidopsis , Evolução Biológica , Hordeum , Peptídeo Hidrolases/metabolismo , Arabidopsis/classificação , Arabidopsis/metabolismo , Proteínas de Bactérias/genética , Hordeum/classificação , Hordeum/metabolismo , Filogenia , Doenças das Plantas/imunologia , Pseudomonas syringae/enzimologia
20.
J Am Acad Dermatol ; 81(5): 1115-1119, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30776397

RESUMO

BACKGROUND: Total-body skin examinations (TBSEs) are commonly performed in clinical practice. There is limited research on best practices for performing a TBSE. OBJECTIVE: To optimize the TBSE. METHODS: We performed an observational cohort study by video recording 5 dermatology faculty and 5 residents conducting their regular TBSE on both a healthy male and female patient. Examination time, physician movements, patient movements, sequence of body parts examined, and body parts missed were analyzed by using an analytic hierarchy process matrix. Differences were evaluated by a t test of unequal variance. P values < .05 were deemed significant. RESULTS: We identified an optimal format for conducting a TBSE that is efficient and accurate. LIMITATIONS: This study was conducted with only standard healthy examiners and patients, rather than individuals with a variety of physical or mental disabilities. The structure of the study was not hypothesis driven, and we assumed that the engineers observing the physicians performing the examination would identify the most optimal TBSE. CONCLUSION: Our results indicate that a standardized process of performing a TBSE minimizes the chance of missing a body area. This could also have implications on teaching a standardized TBSE to medical students, residents, and physicians.


Assuntos
Detecção Precoce de Câncer/métodos , Exame Físico , Neoplasias Cutâneas/diagnóstico , Estudos de Coortes , Feminino , Humanos , Masculino , Exame Físico/métodos , Exame Físico/normas
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