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1.
Chem Soc Rev ; 53(14): 7590-7631, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38904177

RESUMO

The Golgi apparatus is an essential organelle constructed by the stacking of flattened vesicles, that is widely distributed in eukaryotic cells and is dynamically regulated during cell cycles. It is a central station which is responsible for collecting, processing, sorting, transporting, and secreting some important proteins/enzymes from the endoplasmic reticulum to intra- and extra-cellular destinations. Golgi-specific fluorescent probes provide powerful non-invasive tools for the real-time and in situ visualization of the temporal and spatial fluctuations of bioactive species. Over recent years, more and more Golgi-targeting probes have been developed, which are essential for the evaluation of diseases including cancer. However, when compared with systems that target other important organelles (e.g. lysosomes and mitochondria), Golgi-targeting strategies are still in their infancy, therefore it is important to develop more Golgi-targeting probes. This review systematically summarizes the currently reported Golgi-specific fluorescent probes, and highlights the design strategies, mechanisms, and biological uses of these probes, we have structured the review based on the different targeting groups. In addition, we highlight the future challenges and opportunities in the development of Golgi-specific imaging agents and therapeutic systems.


Assuntos
Corantes Fluorescentes , Complexo de Golgi , Complexo de Golgi/metabolismo , Corantes Fluorescentes/química , Humanos , Animais
2.
Semin Cancer Biol ; 93: 114-122, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37225047

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer that is characterised by a prominent collagenous stromal reaction/desmoplasia surrounding tumour cells. Pancreatic stellate cells (PSCs) are responsible for the production of this stroma and have been shown to facilitate PDAC progression. Recently, extracellular vesicles (EVs), in particular, small extracellular vesicles (exosomes) have been a topic of interest in the field of cancer research for their emerging roles in cancer progression and diagnosis. EVs act as a form of intercellular communication by carrying their molecular cargo from one cell to another, regulating functions of the recipient cells. Although the knowledge of the bi-directional interactions between the PSCs and cancer cells that promote disease progression has advanced significantly over the past decade, studies on PSC-derived EVs in PDAC are currently rather limited. This review provides an overview of PDAC, pancreatic stellate cells and their interactions with cancer cells, as well as the currently known role of extracellular vesicles derived from PSCs in PDAC progression.


Assuntos
Carcinoma Ductal Pancreático , Vesículas Extracelulares , Neoplasias Pancreáticas , Humanos , Células Estreladas do Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Vesículas Extracelulares/patologia
3.
Proteomics ; 24(11): e2300067, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38570832

RESUMO

Small extracellular vesicles (sEVs) are cell-derived vesicles evolving as important elements involved in all stages of cancers. sEVs bear unique protein signatures that may serve as biomarkers. Pancreatic cancer (PC) records a very poor survival rate owing to its late diagnosis and several cancer cell-derived proteins have been reported as candidate biomarkers. However, given the pivotal role played by stellate cells (PSCs, which produce the collagenous stroma in PC), it is essential to also assess PSC-sEV cargo in biomarker discovery. Thus, this study aimed to isolate and characterise sEVs from mouse PC cells and PSCs cultured alone or as co-cultures and performed proteomic profiling and pathway analysis. Proteomics confirmed the enrichment of specific markers in the sEVs compared to their cells of origin as well as the proteins that are known to express in each of the culture types. Most importantly, for the first time it was revealed that PSC-sEVs are enriched in proteins (including G6PI, PGAM1, ENO1, ENO3, and LDHA) that mediate pathways related to development of diabetes, such as glucose metabolism and gluconeogenesis revealing a potential role of PSCs in pancreatic cancer-related diabetes (PCRD). PCRD is now considered a harbinger of PC and further research will enable to identify the role of these components in PCRD and may develop as novel candidate biomarkers of PC.


Assuntos
Vesículas Extracelulares , Neoplasias Pancreáticas , Células Estreladas do Pâncreas , Proteômica , Animais , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Células Estreladas do Pâncreas/metabolismo , Células Estreladas do Pâncreas/patologia , Camundongos , Vesículas Extracelulares/metabolismo , Proteômica/métodos , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proteoma/análise , Proteoma/metabolismo
4.
Cancer Invest ; 42(5): 408-415, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38785094

RESUMO

A retrospective study on 90 eligible HER2+ ductal carcinoma in situ with microinvasion (DCIS-MI) patients was performed with a median follow-up time of 57 months. The baseline was consistent between the 4-cycle and 6-cycle chemotherapy groups. There were more patients with multiple foci of micrometastasis in the target therapy group in the two groups with or without target therapy (p < 0.01). Postoperative chemotherapy with a 4-cycle regimen can achieve the expected therapeutic effect in patients with HER2+ DCIS-MI, but the role of target therapy in HER2+ DCIS-MI patients has not been confirmed.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Receptor ErbB-2 , Humanos , Feminino , Receptor ErbB-2/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Neoplasias da Mama/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos , Quimioterapia Adjuvante , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/tratamento farmacológico , Carcinoma Intraductal não Infiltrante/cirurgia , Carcinoma Intraductal não Infiltrante/metabolismo , Adulto , Idoso , Invasividade Neoplásica , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
5.
Cerebellum ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429489

RESUMO

COQ8A plays an important role in the biosynthesis of coenzyme Q10 (CoQ10), and variations in COQ8A gene are associated with primary CoQ10 deficiency-4 (COQ10D4), also known as COQ8A-ataxia. The current understanding of the association between the specific variant type, the severity of CoQ10 deficiency, and the degree of oxidative stress in individuals with primary CoQ10 deficiencies remains uncertain. Here we provide a comprehensive analysis of the clinical and genetic characteristics of an 18-year-old patient with COQ8A-ataxia, who exhibited novel compound heterozygous variants (c.1904_1906del and c.637C > T) in the COQ8A gene. These variants reduced the expression levels of COQ8A and mitochondrial proteins in the patient's muscle and skin fibroblast samples, contributed to mitochondrial respiration deficiency, increased ROS production and altered mitochondrial membrane potential. It is worth noting that the optimal treatment for COQ8A-ataxia remains uncertain. Presently, therapy consists of CoQ10 supplementation, however, it did not yield significant improvement in our patient's symptoms. Additionally, we reviewed the response of CoQ10 supplementation and evolution of patients in previous literatures in detail. We found that only half of patients could got notable improvement in ataxia. This research aims to expand the genotype-phenotype spectrum of COQ10D4, address discrepancies in previous reviews regarding the effectiveness of CoQ10 in these disorders, and help to establish a standardized treatment protocol for COQ8A-ataxia.

6.
Parasitology ; 151(5): 514-522, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629119

RESUMO

With many non-human primates (NHPs) showing continued population decline, there is an ongoing need to better understand their ecology and conservation threats. One such threat is the risk of disease, with various bacterial, viral and parasitic infections previously reported to have damaging consequences for NHP hosts. Strongylid nematodes are one of the most commonly reported parasitic infections in NHPs. Current knowledge of NHP strongylid infections is restricted by their typical occurrence as mixed infections of multiple genera, which are indistinguishable through traditional microscopic approaches. Here, modern metagenomics approaches were applied for insight into the genetic diversity of strongylid infections in South-East and East Asian NHPs. We hypothesized that strongylid nematodes occur in mixed communities of multiple taxa, dominated by Oesophagostomum, matching previous findings using single-specimen genetics. Utilizing the Illumina MiSeq platform, ITS-2 strongylid metabarcoding was applied to 90 samples from various wild NHPs occurring in Malaysian Borneo and Japan. A clear dominance of Oesophagostomum aculeatum was found, with almost all sequences assigned to this species. This study suggests that strongylid communities of Asian NHPs may be less species-rich than those in African NHPs, where multi-genera communities are reported. Such knowledge contributes baseline data, assisting with ongoing monitoring of health threats to NHPs.


Assuntos
Variação Genética , Primatas , Animais , Primatas/parasitologia , Infecções por Strongylida/veterinária , Infecções por Strongylida/parasitologia , Infecções por Strongylida/epidemiologia , Japão , Doenças dos Macacos/parasitologia , Doenças dos Macacos/epidemiologia , Metagenômica , Estrongilídios/genética , Estrongilídios/classificação , Estrongilídios/isolamento & purificação , Bornéu , Doenças dos Primatas/parasitologia , Filogenia , Oesophagostomum/genética , Oesophagostomum/classificação , População do Leste Asiático
7.
Proc Natl Acad Sci U S A ; 118(22)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34031248

RESUMO

Germ cells (GCs) are the key carriers delivering genetic information from one generation to the next. In a majority of animals, GCs segregate from somatic cells during embryogenesis by forming germlines. In land plants, GCs segregate from somatic cells during postembryonic development. In a majority of angiosperms, male GCs (archesporial cells) initiate at the four corners of the anther primordia. Little is known about the mechanism underlying this initiation. Here, we discovered that the dynamic auxin distribution in developing anthers coincided with GC initiation. A centripetal auxin gradient gradually formed toward the four corners where GCs will initiate. Local auxin biosynthesis was necessary for this patterning and for GC specification. The GC determinant protein SPOROCYTELESS/NOZZLE (SPL/NZZ) mediated the effect of auxin on GC specification and modified auxin biosynthesis to maintain a centripetal auxin distribution. Our work reveals that auxin is a key factor guiding GC specification in Arabidopsis anthers. Moreover, we demonstrate that the GC segregation from somatic cells is not a simple switch on/off event but rather a complicated process that involves a dynamic feedback circuit among local auxin biosynthesis, transcription of SPL/NZZ, and a progressive GC specification. This finding sheds light on the mystery of how zygote-derived somatic cells diverge into GCs in plants.


Assuntos
Arabidopsis/fisiologia , Flores/metabolismo , Gametogênese Vegetal , Células Germinativas Vegetais , Ácidos Indolacéticos/metabolismo , Arabidopsis/citologia , Proteínas de Arabidopsis/metabolismo , Flores/citologia , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo
8.
Mikrochim Acta ; 191(2): 109, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38246895

RESUMO

Household storage of pharmaceuticals to extract raw materials synthesized from carbon points facilitates the utilization of solid waste resources. A novel ratiometric fluorescence sensing technique was developed to ascertain the presence of horseradish peroxidase (HRP) in fruits and vegetables. The method employed a fluorescent probe, synthesized from expired amoxicillin (referred to as carbon dots, or A-CDs), serving as a reference fluorophore. Additionally, 2,3-diaminophenazine (DAP) was utilized as a specific response signal. DAP resulted from a catalytic reaction system involving phenylenediamine and hydrogen peroxide under the catalysis of HRP. The fluorescence intensity corresponding to DAP at 562 nm exhibited a substantial increase, simultaneous with the fluorescence quenching of A-CDs at 450 nm. The ratiometric fluorescence nanosensors displayed a broad linear range and high sensitivity for the detection of HRP. Across the concentration range 0.01 to 6 U L-1, the fluorescence intensity ratio between DAP and A-CDs demonstrated a proportional increase with rising HRP concentration, achieving an impressive detection limit of 0.002 U L-1. The recovery of HRP in fruit and vegetable samples ranged from 96.1 to 103%, with an RSD value of less than 3.8%. The proposed method facilitated the screening of inhibitors of HRP enzyme activity, contributing to the preservation of freshness in fruits and vegetables.


Assuntos
Frutas , Verduras , Corantes Fluorescentes , Carbono , Peroxidase do Rábano Silvestre
9.
Appl Environ Microbiol ; 89(1): e0186222, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36602328

RESUMO

The importance of the rare microbial biosphere in maintaining biodiversity and ecological functions has been highlighted recently. However, the current understanding of the spatial distribution of rare microbial taxa is still limited, with only a few investigations for rare prokaryotes and virtually none for rare fungi. Here, we investigated the spatial patterns of rare and abundant fungal taxa in alpine grassland soils across 2,000 km of the Qinghai-Tibetan plateau. We found that most locally rare fungal taxa remained rare (13.07%) or were absent (82.85%) in other sites, whereas only a small proportion (4.06%) shifted between rare and abundant among sites. Although they differed in terms of diversity levels and compositions, the distance decay relationships of both the rare and the abundant fungal taxa were valid and displayed similar turnover rates. Moreover, the community assemblies of both rare and abundant fungal taxa were predominantly controlled by deterministic rather than stochastic processes. Notably, the community composition of rare rather than abundant fungal taxa associated with the plant community composition. In summary, this study advances our understanding of the biogeographic features of rare fungal taxa in alpine grasslands and highlights the concordance between plant communities and rare fungal subcommunities in soil. IMPORTANCE Our current understanding of the ecology and functions of rare microbial taxa largely relies on research conducted on prokaryotes. Despite the key ecological roles of soil fungi, little is known about the biogeographic patterns and drivers of rare and abundant fungi in soils. In this study, we investigated the spatial patterns of rare and abundant fungal taxa in Qinghai-Tibetan plateau (QTP) alpine grassland soils across 2,000 km, with a special concentration on the importance of the plant communities in shaping rare fungal taxa. We showed that rare fungal taxa generally had a biogeographic pattern that was similar to that of abundant fungal taxa in alpine grassland soils on the QTP. Furthermore, the plant community composition was strongly related to the community composition of rare taxa but not abundant taxa. In summary, this study significantly increases our biogeographic and ecological knowledge of rare fungal taxa in alpine grassland soils.


Assuntos
Pradaria , Solo , Plantas , Biodiversidade , Tibet , Microbiologia do Solo
10.
Plant Physiol ; 188(2): 1111-1128, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34865119

RESUMO

Chromosome segregation must be under strict regulation to maintain chromosome euploidy and stability. Cell Division Cycle 20 (CDC20) is an essential cell cycle regulator that promotes the metaphase-to-anaphase transition and functions in the spindle assembly checkpoint, a surveillance pathway that ensures the fidelity of chromosome segregation. Plant CDC20 genes are present in multiple copies, and whether CDC20s have the same functions in plants as in yeast and animals is unclear, given the potential for divergence or redundancy among the multiple copies. Here, we studied all three CDC20 genes in rice (Oryza sativa) and constructed two triple mutants by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9-mediated genome editing to explore their roles in development. Knocking out all three CDC20 genes led to total sterility but did not affect vegetative development. Loss of the three CDC20 proteins did not alter mitotic division but severely disrupted meiosis as a result of asynchronous and unequal chromosome segregation, chromosome lagging, and premature separation of chromatids. Immunofluorescence of tubulin revealed malformed meiotic spindles in microsporocytes of the triple mutants. Furthermore, cytokinesis of meiosis I was absent or abnormal, and cytokinesis II was completely prevented in all mutant microsporocytes; thus, no tetrads or pollen formed in either cdc20 triple mutant. Finally, the subcellular structures and functions of the tapetum were disturbed by the lack of CDC20 proteins. These findings demonstrate that the three rice CDC20s play redundant roles but are indispensable for faithful meiotic chromosome segregation and cytokinesis, which are required for the production of fertile microspores.


Assuntos
Divisão Celular/genética , Segregação de Cromossomos/genética , Citocinese/genética , Meiose/genética , Oryza/genética , Produtos Agrícolas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas
11.
J Periodontal Res ; 58(2): 403-413, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36653725

RESUMO

BACKGROUND AND OBJECTIVES: Periodontitis is an immunoinflammatory disease characterized by irreversible periodontal attachment loss and bone destruction. Ferroptosis is a kind of immunogenic cell death that depends on the participation of iron ions and is involved in various inflammatory and immune processes. However, information regarding the relationship between ferroptosis and immunomodulation processes in periodontitis is extremely limited. The purpose of this study was to investigate the correlation between ferroptosis and immune responses in periodontitis. METHODS: Gene expression profiles of gingivae were collected from the Gene Expression Omnibus data portal. After detecting differentially expressed ferroptosis-related genes (FRGs), we used univariate logistic regression analysis followed by logistic least absolute shrinkage and selection operator (LASSO) regression to establish a ferroptosis-related classification model in an attempt to accurately distinguish periodontitis gingival tissues from healthy samples. The infiltration level of immunocytes in periodontitis was then assessed through single-sample gene-set enrichment analysis. Subsequently, we screened out immune-related genes by weighted correlation network analysis and protein-protein interaction (PPI) analysis and constructed an immune-related network based on FRGs and immune-related genes. RESULTS: A total of 24 differentially expressed FRGs were detected, and an 8-FRG combined signature constituted the classification model. The established model showed outstanding discriminating ability according to the results of receiver operating characteristic (ROC) curve analysis. In addition, the periodontitis samples had a higher degree of immunocyte infiltration. Activated B cells had the strongest positive correlation while macrophages had a strong negative correlation with certain FRGs, and we found that XBP1, ALOX5 and their interacting genes might be crucial genes in the immune-related network. CONCLUSIONS: The FRG-based classification model had a satisfactory determination ability, which could bring new insights into the pathogenesis of periodontitis. Those genes in the immune-related network, especially hub genes along with XBP1 and ALOX5, would have the potential to serve as promising targets of immunomodulatory treatments for periodontitis.


Assuntos
Ferroptose , Linfócitos B , Gengiva , Nível de Saúde , Imunomodulação
12.
Bioorg Chem ; 131: 106319, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586300

RESUMO

Hypochlorite (ClO-) plays an important role in the human immune defense system, but high concentrations of ClO- in the endoplasmic reticulum (ER) damage cellular proteins, causing ER stress, cell death, and various diseases. Herein, we developed a simple hydrazone probe (1) featuring aggregation-induced ratiometric emission, which would quickly (within 20 s) and sensitively (detection limit of 15.4 µM) respond to ClO- in an almost pure aqueous solution via a fluorescent ratiometric output. Furthermore, the probe was employed to track the level of ClO- in the ER of HeLa cells and zebrafish.


Assuntos
Retículo Endoplasmático , Corantes Fluorescentes , Ácido Hipocloroso , Animais , Humanos , Retículo Endoplasmático/metabolismo , Corantes Fluorescentes/química , Células HeLa , Ácido Hipocloroso/análise , Ácido Hipocloroso/metabolismo , Peixe-Zebra/metabolismo
13.
Pestic Biochem Physiol ; 194: 105502, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532322

RESUMO

Rice sheath blight caused by Rhizoctonia solani Kühn is a major fungal disease that plagues commercially grown rice. Occurring mainly in leaf sheaths and leaves, the disease leads to great losses in food production. ß-amino-butyric acid (BABA) has been demonstrated to activate an induced resistance response and is a potent inducer of broad-spectrum disease resistance in different plant species. In this study, ß-amino-butyric acid conjugate of phenazine-1-carboxylic acid (PCA) with prominent induced resistance to rice sheath blight was tested. The in vitro fungicidal activity, as well as in vivo efficacy, systemicity, induced resistance and defense enzyme activity of BABA conjugate of PCA against R. solani in rice seedlings was systematically evaluated. The results indicated that in vitro fungicidal activity of PCA-ß-aminobutyric acid (4e) against R. solani was lower than that of PCA, but in vivo curative ability of 4e was the highest among all tested compounds. The systemicity tests in rice seedlings revealed that PCA did not possess phloem mobility, while 4e exhibited moderate phloem mobility but much lower thanα-amino-butyric acid conjugate of PCA (4d). In addition, Compound 4e showed the highest induced activity against rice sheath blight. The observed effects of defense enzymes help to explain this high level of induced activity. The current research results indicate that in rice seedlings, BABA conjugate of PCA induce observable resistance to rice sheath blight and exhibit moderate phloem mobility, which could be used as an induced resistance fungicide against rice sheath blight in commercial rice production. The BABA conjugate of PCA might provide a useful example of induced resistance to R. solani.


Assuntos
Oryza , Oryza/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Rhizoctonia , Plântula
14.
Sensors (Basel) ; 23(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36679475

RESUMO

Fringe projection profilometry (FPP) and digital image correlation (DIC) are widely applied in three-dimensional (3D) measurements. The combination of DIC and FPP can effectively overcome their respective shortcomings. However, the speckle on the surface of an object seriously affects the quality and modulation of fringe images captured by cameras, which will lead to non-negligible errors in the measurement results. In this paper, we propose a fringe image extraction method based on deep learning technology, which transforms speckle-embedded fringe images into speckle-free fringe images. The principle of the proposed method, 3D coordinate calculation, and deformation measurements are introduced. Compared with the traditional 3D-DIC method, the experimental results show that this method is effective and precise.


Assuntos
Tecnologia
15.
Sensors (Basel) ; 23(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850860

RESUMO

Recognizing traffic signs is key to achieving safe automatic driving. With the decreasing cost of LiDAR, the accurate extraction of traffic signs using point cloud data has received wide attention. In this study, we propose combining point cloud and image traffic sign extraction: firstly, we use the improved YoloV3 model to detect traffic signs in panoramic images. The specific improvement is that the convolution block attention module is added to the algorithm framework, the traditional K-means clustering algorithm is improved, and Focal Loss is introduced as the loss function. It shows higher accuracy on the TT100K dataset, with a 1.4% improvement in accuracy compared to the previous YoloV3. Then, the point cloud of the area where the traffic sign is located is extracted by combining the image detection results. On this basis, the outline of the traffic sign is accurately extracted using the reflection intensity, spatial geometry and other information. Compared with the traditional method, the proposed method can effectively reduce the missed detection rate, narrow the range of point cloud, and improve the detection accuracy by 10.2%.

16.
Educ Inf Technol (Dordr) ; : 1-18, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36714439

RESUMO

Evaluating the effectiveness of teaching methods for synchronous online instruction is integral to fostering student engagement and maximizing student learning, particularly in one-time workshops or seminars. Using the lens of social constructivism theory, this study investigated the effect of different approaches of synchronous online instruction on the development of graduate students' research data management (RDM) skills during the post-pandemic era. One experimental group received teacher-centered instruction primarily via lecture and the second experimental group received student-centered instruction with active learning activities. A one-way ANCOVA was used to compare the post-test RDM scores between one control group and the two experimental groups, while controlling for the impact of their pre-test RDM scores. Both experimental groups who received online RDM instruction scored higher than participants from the control group who received no instruction. Additionally, our results indicated that learners who were exposed to more engaged and collaborative instruction demonstrated higher learning outcomes than students who received teacher-centered instruction. These findings suggest that interactive teaching that actively engages the audience is essential for successful synchronous online learning. Simply transferring a lecture-based approach to online teaching will not result in optimal student engagement and learning. The interactive online instructional strategies used in this study (e.g., collective note-taking, Google Jamboard activities) can be applied to any instructional content to engage learners and enhance student learning.

17.
PLoS Pathog ; 16(12): e1009118, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33264360

RESUMO

There are 25 auxin response factors (ARFs) in the rice genome, which play critical roles in regulating myriad aspects of plant development, but their role (s) in host antiviral immune defense and the underneath mechanism remain largely unknown. By using the rice-rice dwarf virus (RDV) model system, here we report that auxin signaling enhances rice defense against RDV infection. In turn, RDV infection triggers increased auxin biosynthesis and accumulation in rice, and that treatment with exogenous auxin reduces OsIAA10 protein level, thereby unleashing a group of OsIAA10-interacting OsARFs to mediate downstream antiviral responses. Strikingly, our genetic data showed that loss-of-function mutants of osarf12 or osarf16 exhibit reduced resistance whereas osarf11 mutants display enhanced resistance to RDV. In turn, OsARF12 activates the down-stream OsWRKY13 expression through direct binding to its promoter, loss-of-function mutants of oswrky13 exhibit reduced resistance. These results demonstrated that OsARF 11, 12 and 16 differentially regulate rice antiviral defense. Together with our previous discovery that the viral P2 protein stabilizes OsIAA10 protein via thwarting its interaction with OsTIR1 to enhance viral infection and pathogenesis, our results reveal a novel auxin-IAA10-ARFs-mediated signaling mechanism employed by rice and RDV for defense and counter defense responses.


Assuntos
Ácidos Indolacéticos/imunologia , Oryza/imunologia , Oryza/virologia , Doenças das Plantas/imunologia , Imunidade Vegetal/imunologia , Reoviridae/imunologia , Regulação da Expressão Gênica de Plantas/imunologia , Interações Hospedeiro-Patógeno/imunologia , Doenças das Plantas/virologia , Proteínas de Plantas/imunologia
18.
Plant Physiol ; 186(4): 2003-2020, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-33930167

RESUMO

The quality control system for messenger RNA (mRNA) is fundamental for cellular activities in eukaryotes. To elucidate the molecular mechanism of 3'-phosphoinositide-dependent protein kinase1 (PDK1), a master regulator that is essential throughout eukaryotic growth and development, we employed a forward genetic approach to screen for suppressors of the loss-of-function T-DNA insertion double mutant pdk1.1 pdk1.2 in Arabidopsis thaliana. Notably, the severe growth attenuation of pdk1.1 pdk1.2 was rescued by sop21 (suppressor of pdk1.1 pdk1.2), which harbors a loss-of-function mutation in PELOTA1 (PEL1). PEL1 is a homolog of mammalian PELOTA and yeast (Saccharomyces cerevisiae) DOM34p, which each form a heterodimeric complex with the GTPase HBS1 (HSP70 SUBFAMILY B SUPPRESSOR1, also called SUPERKILLER PROTEIN7, SKI7), a protein that is responsible for ribosomal rescue and thereby assures the quality and fidelity of mRNA molecules during translation. Genetic analysis further revealed that a dysfunctional PEL1-HBS1 complex failed to degrade the T-DNA-disrupted PDK1 transcripts, which were truncated but functional, and thus rescued the growth and developmental defects of pdk1.1 pdk1.2. Our studies demonstrated the functionality of a homologous PELOTA-HBS1 complex and identified its essential regulatory role in plants, providing insights into the mechanism of mRNA quality control.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo
19.
FASEB J ; 35(2): e21347, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33484481

RESUMO

Pancreatic cancer (PaCa) is characterized by dense stroma that hinders treatment efficacy, with pancreatic stellate cells (PSCs) being a major contributor to this stromal barrier and PaCa progression. Activated PSCs release hepatocyte growth factor (HGF) and insulin-like growth factor (IGF-1) that induce PaCa proliferation, metastasis and resistance to chemotherapy. We demonstrate for the first time that the metastasis suppressor, N-myc downstream regulated gene 1 (NDRG1), is a potent inhibitor of the PaCa-PSC cross-talk, leading to inhibition of HGF and IGF-1 signaling. NDRG1 also potently reduced the key driver of PaCa metastasis, namely GLI1, leading to reduced PSC-mediated cell migration. The novel clinically trialed anticancer agent, di-2-pyridylketone 4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC), which upregulates NDRG1, potently de-sensitized PaCa cells to ligands secreted by activated PSCs. DpC and NDRG1 also inhibited the PaCa-mediated activation of PSCs via inhibition of sonic hedgehog (SHH) signaling. In vivo, DpC markedly reduced PaCa tumor growth and metastasis more avidly than the standard chemotherapy for this disease, gemcitabine. Uniquely, DpC was selectively cytotoxic against PaCa cells, while "re-programming" PSCs to an inactive state, decreasing collagen deposition and desmoplasia. Thus, targeting NDRG1 can effectively break the oncogenic cycle of PaCa-PSC bi-directional cross-talk to overcome PaCa desmoplasia and improve therapeutic outcomes.


Assuntos
Adenocarcinoma/metabolismo , Proteínas de Ciclo Celular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pancreáticas/metabolismo , Células Estromais/metabolismo , Adenocarcinoma/patologia , Animais , Antineoplásicos/toxicidade , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Proteínas Hedgehog/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/patologia , Piridinas/toxicidade , Células Estromais/efeitos dos fármacos , Tiossemicarbazonas/toxicidade , Proteína GLI1 em Dedos de Zinco/metabolismo
20.
J Org Chem ; 87(12): 7989-7994, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35618673

RESUMO

It is generally accepted that N-heterocyclic carbene (NHC)-catalyzed imine transformations are initiated by a nucleophilic attack (NA) by NHC. However, due to significant nucleophilicity of the iminyl nitrogen atom in imines, the electrophilic attack (EA) by electrophiles onto imine would also be a possible mechanism of these kinds of reactions. Therefore, we use the quantum mechanical approach to disclose that both the NA and EA modes could be switchable for a wide range of NHC-catalyzed transformations of imines.

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