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Deubiquitinase-targeting chimeras (DUBTACs) have been recently developed to stabilize proteins of interest, which is in contrast to targeted protein degradation (TPD) approaches that degrade disease-causing proteins. However, to date, only the OTUB1 deubiquitinase has been utilized to develop DUBTACs via an OTUB1 covalent ligand, which could unexpectedly compromise the endogenous function of OTUB1 owing to its covalent nature. Here, we show for the first time that deubiquitinase USP7 can be harnessed for DUBTAC development. Based on a noncovalent ligand of USP7, we developed USP7-based DUBTACs that stabilized the ΔF508-CFTR mutant protein as effectively as the previously reported OTUB1-based DUBTAC. Importantly, using two different noncovalent ligands of USP7, we developed the first AMPK DUBTACs that appear to selectively stabilize different isoforms of AMPKß, leading to elevated AMPK signaling. Overall, these results highlight that, in addition to OTUB1, USP7 can be leveraged to develop DUBTACs, thus significantly expanding the limited toolbox for targeted protein stabilization and the development of novel AMPK DUBTACs as potential therapeutics.
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The presence of neurofibrillary tangles containing hyper-phosphorylated tau is a characteristic of Alzheimer's disease (AD) pathology. The positron emission tomography (PET) radioligand sensitive to tau neurofibrillary tangles (18F-AV1451) also binds with iron. This off-target binding effect may be enhanced in older adults on the AD spectrum, particularly those with amyloid-positive biomarkers. Here, we examined group differences in 18F-AV1451 PET after controlling for iron-sensitive measures from magnetic resonance imaging (MRI) and its relationships to tissue microstructure and cognition in 40 amyloid beta positive (Aß+) individuals, 20 amyloid beta negative (Aß-) with MCI and 31 Aß- control participants. After controlling for iron, increased 18F-AV1451 PET uptake was found in the temporal lobe and hippocampus of Aß+ participants compared to Aß- MCI and control participants. Within the Aß+ group, significant correlations were seen between 18F-AV1451 PET uptake and tissue microstructure and these correlations remained significant after controlling for iron. These findings indicate that off-target binding of iron to the 18F-AV1451 ligand may not affect its sensitivity to Aß status or cognition in early-stage AD.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Carbolinas , Disfunção Cognitiva , Ferro , Tomografia por Emissão de Pósitrons , Humanos , Tomografia por Emissão de Pósitrons/métodos , Masculino , Feminino , Idoso , Peptídeos beta-Amiloides/metabolismo , Ferro/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Idoso de 80 Anos ou mais , Córtex Cerebral/metabolismo , Córtex Cerebral/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Hipocampo/metabolismoRESUMO
MOTIVATION: With the rapid advances of RNA sequencing and microarray technologies in non-coding RNA (ncRNA) research, functional tools that perform enrichment analysis for ncRNAs are needed. On the one hand, because of the rapidly growing interest in circRNAs, snoRNAs, and piRNAs, it is essential to develop tools for enrichment analysis for these newly emerged ncRNAs. On the other hand, due to the key role of ncRNAs' interacting target in the determination of their function, the interactions between ncRNA and its corresponding target should be fully considered in functional enrichment. Based on the ncRNA-mRNA/protein-function strategy, some tools have been developed to functionally analyze a single type of ncRNA (the majority focuses on miRNA); in addition, some tools adopt predicted target data and lead to only low-confidence results. RESULTS: Herein, an online tool named RNAenrich was developed to enable the comprehensive and accurate enrichment analysis of ncRNAs. It is unique in (i) realizing the enrichment analysis for various RNA types in humans and mice, such as miRNA, lncRNA, circRNA, snoRNA, piRNA, and mRNA; (ii) extending the analysis by introducing millions of experimentally validated data of RNA-target interactions as a built-in database; and (iii) providing a comprehensive interacting network among various ncRNAs and targets to facilitate the mechanistic study of ncRNA function. Importantly, RNAenrich led to a more comprehensive and accurate enrichment analysis in a COVID-19-related miRNA case, which was largely attributed to its coverage of comprehensive ncRNA-target interactions. AVAILABILITY AND IMPLEMENTATION: RNAenrich is now freely accessible at https://idrblab.org/rnaenr/.
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COVID-19 , MicroRNAs , RNA Longo não Codificante , Humanos , Animais , Camundongos , RNA não Traduzido/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Nucleolar Pequeno , RNA Mensageiro/genética , RNA CircularRESUMO
This study aims to examine the clinical characteristics and outcomes of clinical myocarditis in pediatric patients in China. This is a multicenter retrospective study. Children diagnosed with clinical myocarditis from 20 hospitals in China and admitted between January 1, 2015, and December 30, 2021, were enrolled. The clinical myocarditis was diagnosed based on the "Diagnostic Recommendation for Myocarditis in Children (Version 2018)". The clinical data were collected from their medical records. A total of 1210 patients were finally enrolled in this study. Among them, 45.6% had a history of respiratory tract infection. An abnormal electrocardiogram was observed in 74.2% of patients. Echocardiography revealed that 32.3% of patients had a left ventricular ejection fraction of less than 50%. Cardiac MRI was performed in 4.9% of children with clinical myocarditis, of which 61% showed localized or diffuse hypersignal on T2-weighted images. Serum levels of cardiac troponin I (cTnI), creatine kinase-MB (CK-MB), and N-terminal B-type natriuretic peptide (NT-proBNP) were higher in patients with fulminant myocarditis than in patients with myocarditis, making them potential risk factors for fulminant myocarditis. Following active treatment, 12.1% of patients were cured, and 79.1% were discharged with improvement. CONCLUSION: Clinical myocarditis in children often presents with symptoms outside the cardiovascular system. CK-MB, cTnI, and NT-proBNP are important indicators for assessing clinical myocarditis. The electrocardiogram and echocardiogram findings in children with clinical myocarditis exhibit significant variability but lack specificity. Cardiac MRI can be a useful tool for screening clinical myocarditis. Most children with clinical myocarditis have a favorable prognosis. WHAT IS KNOWN: ⢠Pediatric myocarditis presents complex clinical manifestations and exhibits varying degrees of severity. Children with mild myocarditis generally have a favorable prognosis, while a small number of children with critically ill myocarditis experience sudden onset, hemodynamic disorders, and fatal arrhythmias. Therefore, early diagnosis and timely treatment of myocarditis are imperative. WHAT IS NEW: ⢠To the best of our knowledge, this multicenter retrospective study is the largest ever reported in China, aiming to reveal the clinical characteristics and outcomes of pediatric clinical myocarditis in China. We provided an extensive analysis of the clinical characteristics, diagnosis, treatment, prognosis, and factors impacting disease severity in pediatric clinical myocarditis in China, which provides insights into the epidemiological characteristics of pediatric clinical myocarditis.
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Miocardite , Criança , Humanos , Miocardite/diagnóstico , Miocardite/terapia , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda , Creatina Quinase Forma MB , Arritmias Cardíacas , China/epidemiologiaRESUMO
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the main diseases of wheat worldwide. Mianyang of Sichuan province in Southwest China is one of main regions for winter Pst inoculum production and spring epidemic and provides urediniospores for infecting wheat in the surrounding regions. Understanding the urediniospore dynamics is important to predict and manage stripe rust. In this study, spore trapping coupled with a TaqMan real-time quantitative PCR method was used to monitor airborne Pst urediniospores from December 2019 to December 2022 in Mianyang. Weather conditions (temperature, relative humidity, daily sunshine duration, and precipitation) were collected for the same period. These data were used to study the relationship of airborne urediniospore density with climatic conditions. The results showed that Pst urediniospores were captured all year round, and the annual peak of urediniospore densities occurred in the period from March to April in which the urediniospores accounted for the largest proportion of the annual total urediniospores. The density of urediniospores in the period of March to April was linearly related to the average sunshine duration of 20 days and average temperature of 15 days prior to the final day of a 7-day trapping period. This relationship needs to be tested in other regions where Pst can sporulate during the winter before it can be integrated with Pst infection conditions to predict rust development.
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Doenças das Plantas , Puccinia , Esporos Fúngicos , Triticum , China , Doenças das Plantas/microbiologia , Triticum/microbiologia , Puccinia/fisiologia , Estações do Ano , Temperatura , Basidiomycota/fisiologia , Conceitos MeteorológicosRESUMO
Verticillium dahliae is a soilborne phytopathogenic fungus causing Verticillium wilt on hundreds of plant species. Several sequenced genomes of V. dahliae are available, but functional characterization of most genes has just begun. Based on our previous comparison of the transcriptome from the wild-type and ΔVdCf2 strains, a significant upregulation of the gene cassette, Vd276-280, in the ΔVdCf2 strain was observed. In this study, the functional characterization of the Vd276-280 gene cassette was performed. Agrobacterium-mediated knockout of this gene cassette in V. dahliae significantly inhibited conidiation, melanized microsclerotium formation in the mutant strains, and their virulence towards cotton. Furthermore, deletion of individual genes in the Vd276-280 gene cassette identified that the disruption of VDAG_07276 and VDAG_07280 delayed microsclerotium formation, inhibited conidiation, and reduced virulence towards cotton. Our data suggest that VDAG_07276 and VDAG_07280 in the Vd276-280 gene cassette mainly act as positive regulators of development and virulence in V. dahliae.
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Thyroid cancer is the most prevalent endocrine tumor and its incidence is fast-growing worldwide in recent years. Differentiated thyroid cancer (DTC) is the most common pathological subtype which is typically curable with surgery and Radioactive iodine (RAI) therapy (approximately 85%). Radioactive iodine is the first-line treatment for patients with metastatic Papillary Thyroid Cancer (PTC). However, 60% of patients with aggressive metastasis DTC developed resistance to RAI treatment and had a poor overall prognosis. The molecular mechanisms of RAI resistance include gene mutation and fusion, failure to transport RAI into the DTC cells, and interference with the tumor microenvironment (TME). However, it is unclear whether the above are the main drivers of the inability of patients with DTC to benefit from iodine therapy. With the development of new biological technologies, strategies that bolster RAI function include TKI-targeted therapy, DTC cell redifferentiation, and improved drug delivery via extracellular vesicles (EVs) have emerged. Despite some promising data and early success, overall survival was not prolonged in the majority of patients, and the disease continued to progress. It is still necessary to understand the genetic landscape and signaling pathways leading to iodine resistance and enhance the effectiveness and safety of the RAI sensitization approach. This review will summarize the mechanisms of RAI resistance, predictive biomarkers of RAI resistance, and the current RAI sensitization strategies.
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Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/radioterapia , Radioisótopos do Iodo/uso terapêutico , Biomarcadores , Transdução de Sinais , Microambiente Tumoral/genéticaRESUMO
Resistance to Pseudomonas syringae pv. maculicola 1 (RPM1)-induced protein kinase (RIPK) in Arabidopsis belongs to the receptor-like cytoplasmic kinase (RLCK) family and plays a vital role in immunity. However, the role of RLCKs in the high-temperature seedling-plant (HTSP) resistance of wheat (Triticum aestivum) to Puccinia striiformis f. sp. tritici (Pst), the stripe rust pathogen, remains unclear. Here, we identified a homologous gene of RIPK in wheat, namely TaRIPK. Expression of TaRIPK was induced by Pst inoculation and high temperatures. Silencing of TaRIPK reduced the expression level of TaRPM1, resulting in weaker HTSP resistance. Moreover, TaRIPK interacts with and phosphorylates papain-like cysteine protease 1 (TaPLCP1). Meanwhile, we found that the Pst-secreted protein PSTG_01766 targets TaPLCP1. Transient expression of PSTG_01766 inhibited basal immunity in tobacco (Nicotiana benthamiana) and wheat. The role of PSTG_01766 as an effector involved in HTSP resistance was further supported by host-induced gene silencing and bacterial type three secretion system-mediated delivery into wheat. PSTG_01766 inhibited the TaRIPK-induced phosphorylation of TaPLCP1. Furthermore, PSTG_01766 has the potential to influence the subcellular localization of TaPLCP1. Overall, we suggest that the TaRIPK-TaPLCP1-TaRPM1 module fits the guard model for disease resistance, participating in HTSP resistance. PSTG_01766 decreases HTSP resistance via targeting TaPLCP1. Guarded by wheat and attacked by Pst, TaPLCP1 may serve as a central hub of the defense response. Our findings improve the understanding of the molecular mechanism of wheat HTSP resistance, which may be an important strategy for controlling stripe rust in the face of global warming.
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Basidiomycota , Triticum , Basidiomycota/fisiologia , Resistência à Doença/genética , Papaína/metabolismo , Doenças das Plantas/microbiologia , Proteínas Quinases/metabolismo , Puccinia , Plântula/metabolismo , Temperatura , Nicotiana , Triticum/metabolismoRESUMO
This review summarizes the implications of the primary tumor suppressor protein phosphatase and tensin homolog (PTEN) in aggressive cancer development. PTEN interacts with other cellular proteins or factors suggesting the existence of an intricate molecular network that regulates their oncogenic function. Accumulating evidence has shown that PTEN exists and plays a role in the cytoplasmic organelles and in the nucleus. PTEN blocks phosphoinositide 3-kinases (PI3K)-protein kinase B-mammalian target of rapamycin signaling pathway by dephosphorylating phosphatidylinositol (PI)-3,4,5-triphosphate to PI-4,5-bisphosphate thus counteracting PI3K function. Studies have shown that PTEN expression is tightly regulated at transcriptional, posttranscriptional, and posttranslational levels (including protein-protein interactions and posttranslational modifications). Despite recent advances in PTEN research, the regulation and function of the PTEN gene remain largely unknown. How mutation or loss of specific exons in the PTEN gene occurs and involves in cancer development is not clear. This review illustrates the regulatory mechanisms of PTEN expression and discusses how PTEN participates in tumor development and/or suppression. Future prospects for the clinical applications are also highlighted.
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Biomarcadores Tumorais , Neoplasias , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Neoplasias/patologia , Processamento de Proteína Pós-Traducional , Fosfatidilinositol 3-Quinases/metabolismoRESUMO
With advances in chemically induced proximity technologies, heterobifunctional modalities such as proteolysis targeting chimeras (PROTACs) have been successfully advanced to clinics for treating cancer. However, pharmacologic activation of tumor-suppressor proteins for cancer treatment remains a major challenge. Here, we present a novel Acetylation Targeting Chimera (AceTAC) strategy to acetylate the p53 tumor suppressor protein. We discovered and characterized the first p53Y220C AceTAC, MS78, which recruits histone acetyltransferase p300/CBP to acetylate the p53Y220C mutant. MS78 effectively acetylated p53Y220C lysine 382 (K382) in a concentration-, time-, and p300-dependent manner and suppressed proliferation and clonogenicity of cancer cells harboring the p53Y220C mutation with little toxicity in cancer cells with wild-type p53. RNA-seq studies revealed novel p53Y220C-dependent upregulation of TRAIL apoptotic genes and downregulation of DNA damage response pathways upon acetylation induced by MS78. Altogether, the AceTAC strategy could provide a generalizable platform for targeting proteins, such as tumor suppressors, via acetylation.
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Proteína Supressora de Tumor p53 , Acetilação , Humanos , Linhagem Celular Tumoral , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética , Mutação , Modelos Moleculares , Processamento de Proteína Pós-Traducional , Estrutura Terciária de ProteínaRESUMO
Fusarium head blight (FHB) is a major disease worldwide on cultivated cereals, caused by several Fusarium species. FHB can cause not only yield reduction but also accumulation of mycotoxins in the grain contaminating the food supply. Much of the earlier research has focused on Fusarium pathogenesis, conditions required for disease development and toxin accumulation, and FHB management. However, the Fusarium community composition within the micro-habitat of a single diseased wheat head in the field has had limited investigation. Similarly, the relationship between the Fusarium community structure and mycotoxin accumulation within diseased heads remains unclear. In the present study, we investigated the Fusarium community in diseased heads sampled from different geographical sites in China. Several sites in Shandong province formed a transitional region which contained highly variable profiles of Fusarium OTUs, where a single diseased head could contain more than 10 Fusarium OTUs. Mycotoxin accumulation was independent of geographical properties, however, deoxynivalenol, 15-acetyldeoxynivalenol and zearalenone concentrations showed a significant negative correlation with Fusarium diversity on diseased heads while a significant positive correlation between nivalenol concentration and Fusarium diversity was observed. Taken together, the Fusarium OTU diversity within diseased heads in the field significantly influences mycotoxin accumulation, providing an important point to consider in FHB disease management and mycotoxin research.
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Fusarium , Micotoxinas , Micotoxinas/análise , Fusarium/genética , Triticum , Doenças das Plantas , Grão Comestível/químicaRESUMO
Early diagnosis of Alzheimer's disease (AD) is critical for preventing disease progression, however, the diagnosis of AD remains challenging for most patients due to limitations of current sensing technologies. A common pathological feature found in AD-affected brains is the accumulation of Amyloid-ß (Aß) polypeptides, which lead to neurofibrillary tangles and neuroinflammatory plaques. Here, we developed a portable ultrasensitive FET biosensor chip based on a self-assembled nanoporous membrane for ultrasensitive detection of Aß protein in complex environments. The microscale semiconductor channel was covered with a self-assembled organic nanoporous membrane modified by antibody molecules to pick up and amplify the Aß protein signal. The nanoporous structure helps protect the sensitive channel from non-target proteins and improves its stability since no chemical functionalization process involved, largely reduces background noise of the sensing platform. When a bio-gated target is captured, the doping state of the polymer bulk could be tuned and amplified the strength of the weak signal, achieving ultrasensitive detecting performance (enabling the device to detect target protein less than 1 fg/ml in 1 µl sample). Moreover, the device simplifies the circuit connection by integrating all the connections on a 2 cm × 2 cm chip, avoiding expensive and complex manufacturing processes, and makes it usable for portable prognosis. We believe that this ultrasensitive, portable, low-cost Aß sensor chip shows the great potential in the early diagnosis of AD and large-scale population screening applications.
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Doença de Alzheimer , Técnicas Biossensoriais , Nanoporos , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/análise , Emaranhados Neurofibrilares/patologiaRESUMO
Type 2C protein phosphatases regulate various biological processes in eukaryotes. However, their functions in Verticillium dahliae have not been characterized. In this study, homologs VdPtc1, VdPtc3, VdPtc5, VdPtc6, and VdPtc7 were identified in V. dahliae on the basis of homologous comparison with those in Saccharomyces cerevisiae. VdPtc2 and VdPtc4 are missing in the genome of the V. dahliae XJ592 strain. VdPtc3 is the homolog of Ptc2, Ptc3, and Ptc4 proteins in S. cerevisiae, implying that VdPtc3 may play versatile functions in V. dahliae. VdPtc3 promoted conidium development, melanin, and microsclerotium formation in V. dahliae. The ΔVdPtc3 strains showed increased sensitivity to NaCl and sorbitol and augmented the phosphorylation of p38 mitogen-activated protein kinase homolog Hog1 induced by osmotic stress. Besides, the ΔVdPtc3 strains also showed milder Verticillium wilt symptom on cotton. Furthermore, VdPtc3 interacts with VdAtg1, which modulates melanin and microsclerotium formation, as well as pathogenicity.
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Ascomicetos , Verticillium , Virulência , Saccharomyces cerevisiae , Melaninas/genética , Melaninas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Doenças das Plantas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMO
Somatic embryogenesis receptor kinases (SERKs) belong to the leucine-rich repeat receptor-like kinase (LRR-RLK) subfamily, and many LRR-RLKs have been proven to play a key role in plant immune signal transmission. However, the functions of SERKs in resistance to stripe rust caused by Puccinia striiformis f. sp. tritici remains unknown. Here, we identified a gene, TaSERK1, from Xiaoyan 6, a wheat cultivar possessing high-temperature seedling-plant (HTSP) resistance to the fungal pathogen P. striiformis f. sp. tritici and expresses its resistance at the seedling stage. The expression level of TaSERK1 was upregulated upon P. striiformis f. sp. tritici inoculation under relatively high temperatures. The transcriptional level of TaSERK1 was significantly increased under exogenous salicylic acid and brassinosteroids treatments. The barley stripe mosaic virus-induced gene silencing assay indicated that TaSERK1 positively regulated the HTSP resistance to stripe rust. The transient expression of TaSERK1 in tobacco leaves confirmed its subcellular localization on the plasma membrane. Furthermore, TaSERK1 interacted with and phosphorylated the chaperone protein TaDJA7, which belongs to the heat shock protein 40 subfamily. Silencing TaDJA7 compromised the HTSP resistance to stripe rust. The results indicated that when the membrane immune receptor TaSERK1 perceives the P. striiformis f. sp. tritici infection under relatively high temperatures, it transmits the signal to TaDJA7 to activate HTSP resistance to the pathogen.
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Basidiomycota , Plântula , Plântula/genética , Plântula/microbiologia , Leucina , Temperatura , Proteínas de Repetições Ricas em Leucina , Doenças das Plantas/microbiologia , Basidiomycota/fisiologiaRESUMO
BACKGROUND: Radiotherapy is an essential treatment for chest cancer. Radiation-induced pulmonary fibrosis (RIPF) is an almost irreversible interstitial lung disease; however, its pathogenesis remains unclear. METHODS: We analyzed specific changes in cell populations and potential markers by using single-cell sequencing datasets from the Sequence Read Archive database, PERFORMED from control (0 Gy) and thoracic irradiated (20 Gy) mouse lungs at day 150 post-radiation. We performed IHC and ELISA on lung tissue and cells to validate the potential marker cytokines identified by the analysis on rat thoracic irradiated molds (30 Gy). RESULTS: Single-cell sequencing analysis showed changes in abundance across cell types and at the single-cell level, with B and T cells showing the most significant changes in abundance. And four cytokines, CCL5, ICAM1, PF4, and TNF, were significantly upregulated in lung tissues of RIPF rats and cell supernatants after ionizing radiation. CONCLUSION: Cytokines CCL5, ICAM1, PF4, and TNF may play essential roles in radiation pulmonary fibrosis. They are potential targets for the treatment of radiation pulmonary fibrosis.
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Fibrose Pulmonar , Lesões por Radiação , Pneumonite por Radiação , Camundongos , Ratos , Animais , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Citocinas/metabolismo , Pneumonite por Radiação/etiologia , Pulmão/patologia , Camundongos Endogâmicos C57BLRESUMO
Aegilops species are wheat relatives that harbor valuable disease resistance genes for wheat breeding. The wheat Yr8 near-isogenic line, AvSYr8NIL, has long been believed to carry only Yr8 for race-specific all-stage resistance to stripe rust, caused by Puccinia striiformis f. sp. tritici, derived from Aegilops comosa. However, AvSYr8NIL has been found to have high-temperature adult-plant (HTAP) resistance in our field and greenhouse tests. To confirm both HTAP and Yr8 resistance, seeds from AvSYr8NIL were treated with ethyl methanesulfonate to generate mutant lines. The mutant lines with only Yr8 (M641) and only HTAP resistance (M488) were crossed with the susceptible recurrent parent, Avocet S (AvS). The F1 and F4 lines of AvS/M641 were phenotyped with Yr8-avirulent races in the seedling stage at the low-temperature (4-20oC) profile, while the F1, F2, F4, and F5 lines of AvS/M488 were phenotyped with Yr8-virulent races in the adult-plant stage at the high-temperature (10-30oC) profile. Both Yr8 and the HTAP resistance gene (YrM488) were recessive. The F4 populations of AvS/M641 and AvS/M488 were genotyped using polymorphic Kompetitive allele-specific PCR markers converted from SNPs. Yr8 was mapped to a 0.66 cM fragment and YrM488 to a 1.22 cM interval on chromosome 2D. The physical distance between the two resistance genes was estimated to be over 500 Mb, indicating their distinct loci. The mutant lines with separated resistance genes would be useful in enhancing our understanding of different types of resistance and in further studying the interactions between wheat and the stripe rust pathogen.
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Verticillium wilt is primarily caused by the fungus Verticillium dahliae and represents one of the most important worldwide soilborne plant diseases. The causal agent can be spread by microsclerotia and conidia attached to seeds during national/international trade or in soil between fields. Consequently, accurate, sensitive, and rapid detection of V. dahliae from complex samples is critical for restricting entry of the pathogen to a new region/environment and enforcing early management of Verticillium wilt. Based on CRISPR/Cas12a and recombinant polymerase amplification (RPA) technologies, we developed an accurate, sensitive, and rapid detection method for V. dahliae with paper-based lateral flow strips. A highly efficient and specific CRISPR RNA (crRNA) was designed for the GAPDH gene of V. dahliae and was validated using several closely related Verticillium spp. Excluding the time required for the DNA extraction from the complex samples, a minimum of 40 min was required for the detection time. The RPA-CRISPR/Cas12a detection system had a lower detection limit of â¼10 copies of genomic DNA per reaction and was able to successfully detect as little as one microsclerotium per gram of soil. In addition, field samples displaying symptoms suggestive of V. dahliae were able to be positively identified for the presence of V. dahliae. Taken together, this study broadens the applications of CRISPR/Cas12a nucleic acid detection to soilborne crop diseases and will contribute to the future development of field-deployable diagnostic tools.
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Ascomicetos , Sistemas CRISPR-Cas , Comércio , Internacionalidade , Solo , TecnologiaRESUMO
Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici Erikss. (Pst), is a devastating disease resulting in yield reduction. Because the temperature limits the overwintering and oversummering of Pst, it cannot complete the whole year cycle in most areas of China. Longnan, located in the southeast of Gansu Province, is one of the annual cycle areas of Pst, which can supply urediniospores in autumn to eastern wheat-growing areas in China. In this study, a TaqMan real-time quantitative PCR (TaqMan-qPCR) detection system for Pst urediniospores was established, and the detection limit was a single urediniospore. The dynamics of Pst urediniospores in Longnan were monitored by spore trapping and TaqMan-qPCR for 3 years. Meanwhile, the meteorological conditions including air temperature, relative humidity, and precipitation were recorded. Results showed that Pst urediniospores can be captured from March to December, and two peaks of urediniospore density appeared in May and June, respectively. The density of urediniospore is closely related to temperature and precipitation from March to June. In addition, we found that the density of Pst urediniospore had the peak value when the average air temperature was 10 to 21°C, and the relative humidity was 60 to 85% from May to June. The exponential model could describe the variation of Pst urediniospore density based on average temperature and precipitation from March to June. It is worth mentioning that the exponential model based on average temperature 7 days before spore capture has a great advantage in predicting the urediniospore density in the air. This study laid a foundation for establishment of a prediction model for wheat stripe rust based on the density of urediniospores and meteorological factors.
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Basidiomycota , Doenças das Plantas , Puccinia , Basidiomycota/genética , ChinaRESUMO
Wheat near-isogenic line AvSYr17NIL carrying Yr17, originally from Aegilops ventricosa for all-stage resistance to Puccinia striiformis f. sp. tritici, also shows nonrace-specific, high-temperature adult-plant (HTAP) resistance to the stripe rust pathogen. To separate and identify the HTAP resistance gene, seeds of AvSYr17NIL were treated with ethyl methanesulfonate. Mutant lines with only HTAP resistance were obtained, and one of the lines, M1225, was crossed with the susceptible recurrent parent Avocet S (AvS). Field responses of the F2 plants and F3 lines, together with the parents, were recorded at the adult-plant stage in Pullman and Mount Vernon, WA under natural P. striiformis f. sp. tritici infection. The parents and the F4 population were phenotyped with a Yr17-virulent P. striiformis f. sp. tritici race in the adult-plant stage under the high-temperature profile in the greenhouse. The phenotypic results were confirmed by testing the F5 population in the field under natural P. striiformis f. sp. tritici infection. The F2 data indicated a single recessive gene, temporarily named YrM1225, for HTAP resistance. The F4 lines were genotyped with Kompetitive allele-specific PCR markers converted from single-nucleotide polymorphism markers polymorphic between M1225 and AvS. The HTAP resistance gene was mapped on the short arm of chromosome 2A in an interval of 7.5 centimorgans using both linkage and quantitative trait locus mapping approaches. The separation of the HTAP resistance gene from Yr17 should improve the understanding and utilization of the different types of resistance.
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Aegilops , Basidiomycota , Aegilops/genética , Locos de Características Quantitativas , Temperatura , Mapeamento Cromossômico , Basidiomycota/fisiologiaRESUMO
Seeds play a critical role in the production of American ginseng. Seeds are also one of the most important media for the long-distant dissemination and the crucial way for pathogen survival. Figuring out the pathogens carried by seeds is the basis for effective management of seedborne diseases. In this paper, we tested the fungi carried by the seeds of American ginseng from the main production areas of China using incubation and highly throughput sequencing methods. The seed-carried rates of fungi in Liuba, Fusong, Rongcheng, and Wendeng were 100, 93.8, 75.2, and 45.7%, respectively. Sixty-seven fungal species, which belonged to 28 genera, were isolated from the seeds. Eleven pathogens were identified from the seed samples. Among the pathogens, Fusarium spp. were found in all of the seed samples. The relative abundance of Fusarium spp. in the kernel was higher than that in the shell. Alpha index showed that the fungal diversity between seed shell and kernel differed significantly. Nonmetric multidimensional scaling analysis revealed that the samples from different provinces and between seed shell and kernel were distinctly separated. The inhibition rates of four fungicides to seed-carried fungi of American ginseng were 71.83% for Tebuconazole SC, 46.67% for Azoxystrobin SC, 46.08% for Fludioxonil WP, and 11.11% for Phenamacril SC. Fludioxonil, a conventional seed treatment agent, showed a low inhibitory effect on seed-carried fungi of American ginseng.