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1.
Plant Cell ; 35(5): 1572-1592, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36762404

RESUMO

Mitogen-activated protein (MAP) kinase signaling cascades play important roles in eukaryotic defense against various pathogens. Activation of the extracellular ATP (eATP) receptor P2K1 triggers MAP kinase 3 and 6 (MPK3/6) phosphorylation, which leads to an elevated plant defense response. However, the mechanism by which P2K1 activates the MAPK cascade is unclear. In this study, we show that in Arabidopsis thaliana, P2K1 phosphorylates the Raf-like MAP kinase kinase kinase (MAPKKK) INTEGRIN-LINKED KINASE 5 (ILK5) on serine 192 in the presence of eATP. The interaction between P2K1 and ILK5 was confirmed both in vitro and in planta and their interaction was enhanced by ATP treatment. Similar to P2K1 expression, ILK5 expression levels were highly induced by treatment with ATP, flg22, Pseudomonas syringae pv. tomato DC3000, and various abiotic stresses. ILK5 interacts with and phosphorylates the MAP kinase MKK5. Moreover, phosphorylation of MPK3/6 was significantly reduced upon ATP treatment in ilk5 mutant plants, relative to wild-type (WT). The ilk5 mutant plants showed higher susceptibility to P. syringae pathogen infection relative to WT plants. Plants expressing only the mutant ILK5S192A protein, with decreased kinase activity, did not activate the MAPK cascade upon ATP addition. These results suggest that eATP activation of P2K1 results in transphosphorylation of the Raf-like MAPKKK ILK5, which subsequently triggers the MAPK cascade, culminating in activation of MPK3/6 associated with an elevated innate immune response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , MAP Quinase Quinase Quinases/genética , Proteínas de Arabidopsis/metabolismo , Imunidade Inata , Receptores Purinérgicos/metabolismo , Trifosfato de Adenosina/metabolismo , Pseudomonas syringae/fisiologia , Regulação da Expressão Gênica de Plantas , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Imunidade Vegetal/genética
2.
Drug Resist Updat ; 67: 100915, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36641841

RESUMO

AIMS: This study aims at investigating the role of a neighbor long non-coding RNA (lncRNA) of HDAC4 (LOC85009) in docetaxel (DTX) resistance of lung adenocarcinoma (LUAD). METHODS: RT-qPCR was used to analyze LOC85009 expression in DTX-resistant LUAD cells. In vitro and in vivo experiments were applied to detect the influence of LOC85009 on LUAD cell growth and xenograft tumor growth. DNA pull down assay, RNA pull down assay, ChIP assay, CoIP assay and RIP assay were performed to identify the direct interactions between factors. RESULTS: LOC85009 was lowly-expressed in DTX-resistant LUAD cells. Functionally, LOC85009 overexpression inhibited DTX resistance and cell proliferation but triggered cell apoptosis. Moreover, we identified that LOC85009 was transferred from LUAD cells to DTX-resistant LUAD cells via exosomes. Exosomal LOC85009 inhibited DTX resistance, proliferation and autophagy while induced apoptosis in DTX-resistant cells. Additionally, we found that LOC85009 sequestered ubiquitin-specific proteinase 5 (USP5) to destabilize upstream transcription factor 1 (USF1) protein, thereby inactivating ATG5 transcription. CONCLUSIONS: Exosomal LOC85009 inhibits DTX resistance through regulation of ATG5-induced autophagy via USP5/USF1 axis, suggesting that LOC85009 might be a potential target to reverse DTX resistance in the treatment of LUAD.


Assuntos
Adenocarcinoma , Docetaxel , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , MicroRNAs , Humanos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Autofagia/genética , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 5 Relacionada à Autofagia/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , MicroRNAs/genética
3.
Drug Resist Updat ; 68: 100933, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36821972

RESUMO

Alternative polyadenylation (APA) is a widespread mechanism generating RNA molecules with alternative 3' ends. Herein, we discovered that TargetScan includes a novel XBP1 transcript with a longer 3' untranslated region (UTR) (XBP1-UL) than that included in NCBI. XBP1-UL exhibited a lowered level in blood samples from lung adenocarcinoma (LUAD) patients and in those after DDP treatment. Consistently, XBP1-UL was reduced in A549 cells compared to normal BEAS-2B cells, as well as in DDP-treated/resistant A549 cells relative to controls. Moreover, due to decreased usage of the distal polyadenylation site (PAS) in 3'UTR, XBP1-UL level was lowered in A549 cells and decreased further in DDP-resistant A549 (A549/DDP) cells. Importantly, use of the distal PAS (dPAS) and XBP1-UL level were gradually reduced in A549 cells under increasing concentrations of DDP, which was attributed to DDP-induced endoplasmic reticulum (ER) stress. Furthermore, XBP1 transcripts with shorter 3'UTR (XBP1-US) were more stable and presented stronger potentiation on DDP resistance. The choice of proximal PAS (pPAS) was attributed to CPSF6 elevation, which was caused by BRCA1-distrupted R-loop accumulation in CPSF6 5'end. DDP-induced nuclear LINC00221 also facilitated CPSF6-induced pPAS choice in the pre-XBP1 3'end. Finally, we found that unlike the unspliced XBP1 protein (XBP1-u), the spliced form XBP1-s retarded p53 degradation to facilitate DNA damage repair of LUAD cells. The current study provides new insights into tumor progression and DDP resistance in LUAD, which may contribute to improved LUAD treatment.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Regiões 3' não Traduzidas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Resistencia a Medicamentos Antineoplásicos/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Linhagem Celular Tumoral , Apoptose , Proteína 1 de Ligação a X-Box/genética
4.
J Stroke Cerebrovasc Dis ; 32(4): 107037, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36745952

RESUMO

BACKGROUND: We aimed to develop and validate a clinical score to identify the factors which contribute to variation in, and influence clinician's decision-making about treating acute ischemic stroke (AIS) patients with Intravenous thrombolysis (IVT). METHODS: We retrospectively included consecutive AIS patients within 4.5 hours after onset in the emergency department (ED), who were admitted to a comprehensive stroke center in Jiangsu province, China. The patients were randomly divided into derivation (60%) and validation data sets (40%) to develop and validate the clinical score. Multivariable stepwise forward logistic regression was performed to identify the independent predictors of IVT offering in the derivation data. RESULTS: Out of 526 included patients, 418 patients received thrombolytic therapy. Nine patient factors were associated with the likelihood of thrombolysis (age, time to hospital, National Institute of Health stroke scale (NIHSS) score, great vessel, facial paralysis, dizziness, headache, history of stroke, and neutrophil ratio). The c-statistics of the Intravenous Thrombolysis Score in the derivation cohort (n= 316) and validation cohort(n = 210) were 0.795 and 0.751, respectively. The performance of the scoring model was validated with a calibration plot showing good predictive accuracy for the scores in the derivation data (calibrated P = 0.861) and validation data (calibrated P = 0.876). CONCLUSIONS: The Intravenous Thrombolysis Score for predicting the possibility of offering IVT to AIS patients indicates that clinicians differ in their thresholds for the treatment across a number of patient-related factors, which will be linked to training professional development programmes and address the impact of non-medical influences on decision-making using evidence-based strategies.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Fibrinolíticos , Ativador de Plasminogênio Tecidual , AVC Isquêmico/tratamento farmacológico , Estudos Retrospectivos , Isquemia Encefálica/terapia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento
5.
J Stroke Cerebrovasc Dis ; 32(11): 107342, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37689030

RESUMO

BACKGROUND AND PURPOSE: We investigated the association between serum globulin levels upon hospital admission and in-hospital short-term outcomes in acute ischemic stroke (AIS) patients. METHODS: A total of 3,127 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included in the present study. We divided patients into 4 groups according to their level of admission serum globulin: Q1 (<23.5 g/L), Q2 (23.5-26.4 g/L), Q3 (26.4-29.9 g/L), and Q4 (≥29.9 g/L). Logistic regression models were used to estimate the effect of serum globulin on the short-term outcomes, including all cause in-hospital mortality, poor outcome upon discharge (modified Rankin Scale score ≥3) and in-hospital pneumonia in AIS patients. RESULTS: The median National Institutes of Health Stroke Scale (NIHSS) score was 4.0 (IQR, 2.0-7.0). The risk of in-hospital mortality was significantly higher in patients with highest serum globulin level (Q4) compared to those with lowest (Q1) (adjusted odds ratio [OR] 2.30; 95% confidence interval [CI], 1.12-4.70; P-trend =0.026). The highest serum globulin level (Q4) was associated with a 1.32-fold and 1.62-fold increase in the risk of poor outcome upon discharge (adjusted OR 1.32; 95% CI, 1.00-1.75; P-trend = 0.070) and in-hospital pneumonia (adjusted OR 1.62; 95% CI, 1.18-2.23; P-trend = 0.001) in comparison to Q1 after adjustment for potential covariates. CONCLUSIONS: A high level of serum globulin upon hospital admission was independently associated with all cause in-hospital mortality, poor outcome upon discharge and in-hospital pneumonia in relative mild AIS patients.

6.
Mol Cancer ; 21(1): 150, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864549

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) are implicated in the development of multiple cancers. In our previous study, we demonstrated that HDAC1/4-mediated silencing of microRNA-200b (miR-200b) enhances docetaxel (DTX)-resistance of human lung adenocarcinoma (LAD) cells. METHODS AND RESULTS: Herein, we probed the function of LncRNA MARCKSL1-2 (MARCKSL1-transcript variant 2, NR_052852.1) in DTX resistance of LAD cells. It was found that MARCKSL1-2 expression was markedly reduced in DTX-resistant LAD cells. Through gain- or loss- of function assays, colony formation assay, EdU assay, TUNEL assay, and flow cytometry analysis, we found that MARCKSL1-2 suppressed the growth and DTX resistance of both parental and DTX-resistant LAD cells. Moreover, we found that MARCKSL1-2 functioned in LAD through increasing miR-200b expression and repressing HDAC1. Mechanistically, MARCKSL1-2 recruited the suppressor of zeste 12 (SUZ12) to the promoter of histone deacetylase 1 (HDAC1) to strengthen histone H3 lysine 27 trimethylation (H3K27me3) of HDAC1 promoter, thereby reducing HDAC1 expression. MARCKSL1-2 up-regulated miR-200b by blocking the suppressive effect of HDAC1 on the histone acetylation modification at miR-200b promoter. Furthermore, in vivo analysis using mouse xenograft tumor model supported that overexpression of MARCKSL1-2 attenuated the DTX resistance in LAD tumors. CONCLUSIONS: We confirmed that MARCKSL1-2 alleviated DTX resistance in LAD cells by abolishing the inhibitory effect of HDAC1 on miR-200b via the recruitment of SUZ12. MARCKSL1-2 could be a promising target to improve the chemotherapy of LAD.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Adenocarcinoma/genética , Animais , Proteínas de Ligação a Calmodulina/genética , Proteínas de Ligação a Calmodulina/metabolismo , Proteínas de Ligação a Calmodulina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Docetaxel/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 1/genética , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas dos Microfilamentos , RNA Longo não Codificante/genética , Taxoides/farmacologia
7.
BMC Anesthesiol ; 22(1): 371, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456961

RESUMO

Neuroinflammation is the main pathological mechanism of cognitive dysfunction caused by neurodegenerative diseases, and effective preventive and therapeutic measures are not available. We predicted the key targets of gastrodin's effects upon neuroinflammation through Network Pharmacology and molecular docking. Then the predicted targets were used to study how gastrodin affected cognitive dysfunction triggered by lipopolysaccharide-induced neuroinflammation in rats and its mechanisms. Three-month-old male rats were intraperitoneally injected with lipopolysaccharide for 3 days (d), 7 d and 14 d respectively. Gastrodin improved learning and memory ability of rats with neuroinflammation. Lipopolysaccharide enhanced the levels of pro-inflammatory cytokines, such as TNF-α, IL-1ß and IL-6, in rat hippocampus, which could be reversed by gastrodin. Gastrodin also inhibited the activation of microglia. Our findings suggested that gastrodin exerted neuroprotective effects in rats with neuroinflammation by impacting the TLR4-NF-kB-NLRP3 pathway. Therefore, gastrodin may be a potential therapeutic agent for neuroinflammation-induced cognitive dysfunction.


Assuntos
Disfunção Cognitiva , Inflamassomos , Masculino , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR , Lipopolissacarídeos/toxicidade , Simulação de Acoplamento Molecular , Doenças Neuroinflamatórias , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia
8.
Proc Natl Acad Sci U S A ; 111(30): 11199-204, 2014 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-25028496

RESUMO

Tiller angle, a key agronomic trait for achieving ideal plant architecture and increasing grain yield, is regulated mainly by shoot gravitropism. Strigolactones (SLs) are a group of newly identified plant hormones that are essential for shoot branching/rice tillering and have further biological functions as yet undetermined. Through screening for suppressors of lazy1 (sols), a classic rice mutant exhibiting large tiller angle and defective shoot gravitropism, we identified multiple SOLS that are involved in the SL biosynthetic or signaling pathway. We show that SL biosynthetic or signaling mutants can rescue the spreading phenotype of lazy1 (la1) and that SLs can inhibit auxin biosynthesis and attenuate rice shoot gravitropism, mainly by decreasing the local indoleacetic acid content. Although both SLs and LA1 are negative regulators of polar auxin transport, SLs do not alter the lateral auxin transport of shoot base, unlike LA1, which is a positive regulator of lateral auxin transport in rice. Genetic evidence demonstrates that SLs and LA1 participate in regulating shoot gravitropism and tiller angle in distinct genetic pathways. In addition, the SL-mediated shoot gravitropism is conserved in Arabidopsis. Our results disclose a new role of SLs and shed light on a previously unidentified mechanism underlying shoot gravitropism. Our study indicates that SLs could be considered as an important tool to achieve ideal plant architecture in the future.


Assuntos
Gravitropismo/fisiologia , Oryza/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Brotos de Planta/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/fisiologia , Transporte Biológico Ativo/fisiologia , Ácidos Indolacéticos , Oryza/genética , Reguladores de Crescimento de Plantas/genética , Proteínas de Plantas/genética , Brotos de Planta/genética , Proteínas Repressoras/genética
9.
Plant Cell ; 25(5): 1657-73, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23645630

RESUMO

The critical developmental switch from heterotrophic to autotrophic growth of plants involves light signaling transduction and the production of reactive oxygen species (ROS). ROS function as signaling molecules that regulate multiple developmental processes, including cell death. However, the relationship between light and ROS signaling remains unclear. Here, we identify transcriptional modules composed of the basic helix-loop-helix and bZIP transcription factors PHYTOCHROME-INTERACTING FACTOR1 (PIF1), PIF3, ELONGATED HYPOCOTYL5 (HY5), and HY5 HOMOLOGY (HYH) that bridge light and ROS signaling to regulate cell death and photooxidative response. We show that pif mutants release more singlet oxygen and exhibit more extensive cell death than the wild type during Arabidopsis thaliana deetiolation. Genome-wide expression profiling indicates that PIF1 represses numerous ROS and stress-related genes. Molecular and biochemical analyses reveal that PIF1/PIF3 and HY5/HYH physically interact and coordinately regulate the expression of five ROS-responsive genes by directly binding to their promoters. Furthermore, PIF1/PIF3 and HY5/HYH function antagonistically during the seedling greening process. In addition, phytochromes, cryptochromes, and CONSTITUTIVE PHOTOMORPHOGENIC1 act upstream to regulate ROS signaling. Together, this study reveals that the PIF1/PIF3-HY5/HYH transcriptional modules mediate crosstalk between light and ROS signaling and sheds light on a new mechanism by which plants adapt to the light environments.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Nucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas de Transporte/genética , Criptocromos/genética , Criptocromos/metabolismo , Proteínas de Ligação a DNA , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Immunoblotting , Luz , Mutação , Proteínas Nucleares/genética , Fitocromo/genética , Fitocromo/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Plântula/genética , Plântula/metabolismo , Plântula/efeitos da radiação , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Ubiquitina-Proteína Ligases
10.
Plant Cell ; 25(1): 242-56, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23314848

RESUMO

Photomorphogenesis is a critical plant developmental process that involves light-mediated transcriptome changes, histone modifications, and inhibition of hypocotyl growth. However, the chromatin-based regulatory mechanism underlying this process remains largely unknown. Here, we identify ENHANCED PHOTOMORPHOGENIC1 (EPP1), previously known as PICKLE (PKL), an ATP-dependent chromatin remodeling factor of the chromodomain/helicase/DNA binding family, as a repressor of photomorphogenesis in Arabidopsis thaliana. We show that PKL/EPP1 expression is repressed by light in the hypocotyls in a photoreceptor-dependent manner. Furthermore, we reveal that the transcription factor ELONGATED HYPOCOTYL5 (HY5) binds to the promoters of cell elongation-related genes and recruits PKL/EPP1 through their physical interaction. PKL/EPP1 in turn negatively regulates HY5 by repressing trimethylation of histone H3 Lys 27 at the target loci, thereby regulating the expression of these genes and, thus, hypocotyl elongation. We also show that HY5 possesses transcriptional repression activity. Our study reveals a crucial role for a chromatin remodeling factor in repressing photomorphogenesis and demonstrates that transcription factor-mediated recruitment of chromatin-remodeling machinery is important for plant development in response to changing light environments.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , DNA Helicases/genética , Regulação da Expressão Gênica de Plantas , Hipocótilo/genética , Proteínas Nucleares/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Cromatina/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Histonas/genética , Histonas/metabolismo , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/fisiologia , Hipocótilo/efeitos da radiação , Luz , Metilação , Modelos Moleculares , Mutagênese Insercional , Proteínas Nucleares/metabolismo , Fotorreceptores de Plantas , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão , Transcrição Gênica , Técnicas do Sistema de Duplo-Híbrido
11.
Photosynth Res ; 126(2-3): 331-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25910753

RESUMO

Chlorophyll biosynthesis plays a crucial role in the greening process and survival of etiolated seedlings and yet the mechanism underlying the regulation of this process is poorly understood. Upon light stimulation, NADPH: protochlorophyllide oxidoreductase (POR) catalyzes the reduction of protochlorophyllide (Pchlide) to chlorophyllide. Whereas this represents a key step in the chlorophyll biosynthetic pathway, the regulation of POR remains largely unknown. Three POR isoforms exist in Arabidopsis thaliana, i.e., PORA, PORB, and PORC. In this study, we identified a transcription factor, REVEILLE1 (RVE1), that binds directly to the PORA promoter through the EE-box cis-regulatory element. Analysis of PORA expression in RVE1 loss-of-function (rve1) and overexpression (RVE1-OX) Arabidopsis plants showed that RVE1 positively regulates the transcription of PORA. We found that Pchlide levels were reduced in RVE1-OX seedlings. Furthermore, rve1 etiolated seedlings had lower greening rates than the wild type when exposed to light, whereas RVE1-OX seedlings had higher greening rates. In addition, when etiolated seedlings were exposed to light, RVE1-OX plants had less reactive oxygen species (ROS) accumulation and cell death than the wild type, and had reduced levels of ROS-responsive gene expression. Taken together, our study reveals an important role for RVE1 in regulating chlorophyll biosynthesis and promoting seedling greening during early plant growth and development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Protoclorifilida/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Clorofila/metabolismo , Luz , NADP/metabolismo , Plântula/enzimologia , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação , Fatores de Transcrição/genética
12.
Plant Cell ; 24(5): 1984-2000, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22634759

RESUMO

Successful chlorophyll biosynthesis during initial light exposure is critical for plant survival and growth, as excess accumulation of chlorophyll precursors in darkness can cause photooxidative damage to cells. Therefore, efficient mechanisms have evolved to precisely regulate chlorophyll biosynthesis in plants. Here, we identify FAR-RED ELONGATED HYPOCOTYL3 (FHY3) and FAR-RED IMPAIRED RESPONSE1 (FAR1), two transposase-derived transcription factors, as positive regulators of chlorophyll biosynthesis in Arabidopsis thaliana. We show that null mutations in FHY3 and FAR1 cause reduced protochlorophyllide (a precursor of chlorophyll) levels in darkness and less photobleaching in the light. We find that FHY3 directly binds to the promoter and activates expression of HEMB1, which encodes 5-aminolevulinic acid dehydratase in the chlorophyll biosynthetic pathway. We reveal that PHYTOCHROME-INTERACTING FACTOR1 physically interacts with the DNA binding domain of FHY3, thereby partly repressing FHY3/FAR1-activated HEMB1 expression. Strikingly, FHY3 expression is upregulated by white light. In addition, our genetic data indicate that overexpression, severe reduction, or lack of HEMB1 impairs plant growth and development. Together, our findings reveal a crucial role of FHY3/FAR1 in regulating chlorophyll biosynthesis, thus uncovering a new layer of regulation by which light promotes plant dark-light transition in early seedling development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Clorofila/biossíntese , Proteínas Nucleares/metabolismo , Fitocromo/metabolismo , Plântula/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas Nucleares/genética , Fitocromo/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Ligação Proteica/fisiologia , Plântula/genética
13.
Mol Cancer ; 13: 165, 2014 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-24996221

RESUMO

BACKGROUND: Docetaxel resistance remains a major obstacle in the treatment of non-small cell lung cancer (NSCLC). High-mobility group box 1 (HMGB1) has been shown to promote autophagy protection in response to antitumor therapy, but the exact molecular mechanism underlying HMGB1-mediated autophagy has not been clearly defined. METHODS: Lung adenocarcinoma (LAD) cells were transfected with pcDNA3.1-HMGB1 or HMGB1 shRNA, followed by docetaxel treatment. Cell viability and proliferation were tested by MTT assay and colony formation assay, respectively. Annexin V flow cytometric analysis and western blot analysis of activated caspase3 and cleaved PARP were used to evaluate apoptosis, while immunofluorescence microscopy and transmission electron microscopy were applied to assess autophagy activity. The formation of the Beclin-1-PI3K-III complex was examined by immunoprecipitation analysis. NOD/SCID mice were inoculated with docetaxel-resistant SPC-A1/DTX cells transfected with control or HMGB1 shRNA. RESULTS: HMGB1 translocated from the nucleus to the cytoplasm in LAD cells exposed to docetaxel and acted as a positive regulator of autophagy, which inhibited apoptosis and increased drug resistance. Suppression of HMGB1 restored the sensitivity of LAD cells to docetaxel both in vivo and in vitro. Mechanistic investigation revealed that HMGB1 promoted the formation of the Beclin-1-PI3K-III complex through activating the mitogen-activated protein kinase (MEK)-extracellular signal-regulated kinase (ERK) signaling pathway, thereby regulating autophagosome formation. CONCLUSIONS: Our results demonstrated that HMGB1-regulated autophagy is a significant contributor to docetaxel resistance in LAD cells. Suppression of HMGB1 or limiting HMGB1 cytosolic translocation diminished autophagic protection in response to docetaxel in LAD cells.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Autofagia/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína HMGB1/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Taxoides/farmacologia , Adenocarcinoma/enzimologia , Adenocarcinoma/ultraestrutura , Adenocarcinoma de Pulmão , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Linhagem Celular Tumoral , Citoproteção/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Docetaxel , Regulação para Baixo/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/ultraestrutura , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Biológicos , Complexos Multiproteicos/metabolismo , Fosfatidilinositol 3-Quinases , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-38965748

RESUMO

OBJECTIVE: To investigate the role of the microRNA (miRNA)-669f-5p/deoxycytidylate deaminase (Dctd) axis in sevoflurane inducing cognitive dysfunction in aged mice. METHODS: Sixty-six C57BL/6J mice were used in the experiment model and were randomly divided into the sevoflurane group and the control group. The mice in the sevoflurane group were anesthetised with 3.4% sevoflurane, whereas those in the control group were air-treated for the same period. The study was then performed using bioinformatics sequencing, as well as in vitro and in vivo validation. RESULTS: The mice in the sevoflurane group showed significant cognitive impairments in terms of a decrease in both spatial learning and memory abilities. Experimental doses of miR-669f-5p agonist exhibited no obvious effect on cognitive function following sevoflurane inhalation, but inhibiting the expression of miR-669f-5p could alleviate the impairments. Based on the results of the bioinformatics sequencing, miR-669f-5p/Dctd and the toll-like receptor (TLR) signalling pathway could be the key miRNA, gene and pathway leading to postoperative cognitive dysfunction following sevoflurane inhalation. The aged mice showed significantly increased expression of miR-669f-5p in the hippocampus following sevoflurane inhalation, and upregulating/inhibiting its expression could increase/decrease TLR expression in the hippocampus. Furthermore, miR-669f-5p could reduce the expression of the Dctd gene by binding to its 3'untranslated region. CONCLUSION: The miR-669f-5p/Dctd axis plays an important role in sevoflurane inducing cognitive dysfunction in aged mice, providing a new direction for further development of therapeutic strategies concerning the prevention and treatment of cognitive dysfunction associated with sevoflurane anaesthesia.

15.
Photosynth Res ; 117(1-3): 267-79, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23479128

RESUMO

Carotenoids with conjugated carbonyl groups possess special photophysical properties which have been studied in some water-soluble light-harvesting proteins (Polívka and Sundström, Chem Rev 104:2021-2071, 2004). However, siphonaxanthin-type light-harvesting complexes of photosystem II (LHCII) in siphonous green alga have received fewer studies. In the present study, we determined sequences of genes for several Bryopsis corticulans Lhcbm proteins, which showed that they belong to the group of major LHCII and diverged early from green algae and higher plants. Analysis of pigment composition indicated that this siphonaxanthin-type LHCII contained in total 3 siphonaxanthin and siphonein but no lutein and violaxanthin. In addition, 2 chlorophylls a in higher plant LHCII were replaced by chlorophyll b. These changes led to an increased absorption in green and blue-green light region compared with higher plant LHCII. The binding sites for chlorophylls, siphonaxanthin, and siphonein were suggested based on the structural comparison with that of higher plant LHCII. All of the ligands for the chlorophylls were completely conserved, suggesting that the two chlorophylls b were replaced by chlorophyll a without changing their binding sites in higher plant LHCII. Comparisons of the absorption spectra of isolated siphonaxanthin and siphonein in different organic solutions and the effect of heat treatment suggested that these pigments existed in a low hydrophobic protein environment, leading to an enhancement of light harvesting in the green light region. This low hydrophobic protein environment was maintained by the presence of more serine and threonine residues in B. corticulans LHCII. Finally, esterization of siphonein may also contribute to the enhanced harvesting of green light.


Assuntos
Clorófitas/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Xantofilas/metabolismo , Absorção , Proteínas de Algas/química , Sequência de Aminoácidos , Centrifugação com Gradiente de Concentração , Interações Hidrofóbicas e Hidrofílicas , Complexos de Proteínas Captadores de Luz/isolamento & purificação , Dados de Sequência Molecular , Complexo de Proteína do Fotossistema II/isolamento & purificação , Filogenia , Pigmentos Biológicos/metabolismo , Alinhamento de Sequência , Soluções , Solventes , Espectrometria de Fluorescência , Temperatura
16.
Ibrain ; 9(4): 446-462, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38680509

RESUMO

Postoperative cognitive dysfunction (POCD) is a decrease in mental capacity that can occur days to weeks after a medical procedure and may become permanent and rarely lasts for a longer period of time. With the continuous development of research, various viewpoints in academic circles have undergone subtle changes, and the role of anesthesia depth and anesthesia type seems to be gradually weakened; Alzheimer's disease (AD) is a latent and progressive neurodegenerative disease in the elderly. The protein hypothesis and the synaptic hypothesis are well-known reasons. These changes will also lead to the occurrence of an inflammatory cascade. The exact etiology and pathogenesis need to be studied. The reasonable biological mechanism affecting brain protein deposition, neuroinflammation, and acetylcholine-like effect has a certain relationship between AD and POCD. Whereas there is still further uncertainty about the mechanism and treatment, and it is elusive whether POCD is a link in the continuous progress of AD or a separate entity, which has doubts about the diagnosis and treatment of the disease. Therefore, this review is based on the current common clinical characteristics of AD and POCD, and pathophysiological research, to search for their common points and explore the direction and new strategies for future treatment.

17.
J Neuroimmunol ; 379: 578070, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37148600

RESUMO

Microglia-mediated neuroinflammatory responses play a key role in perioperative neurocognitive disorders (PND). Triggering receptor expressed on myeloid cells-1 (TREM1) has been shown to be a key regulator of inflammation. However, its role in PND remains largely unknown. This study aimed to evaluate the role of TREM1 in sevoflurane-induced PND. We applied AAV knockdown TREM1 in hippocampal microglia in aging mice. The mice were then subjected to neurobehavioral and biochemical testing after the intervention of sevoflurane. We found that sevoflurane inhalation can cause PND in mice, increase hippocampal TREM1 expression, polarize microglia to M1 type, upregulate TNF-α and IL-1ß expression (pro-inflammatory), and inhibit TGF-ß and IL-10 expression (anti-inflammatory). Knocking down TREM1 can improve sevoflurane-induced cognitive dysfunction, reduce M1 type marker iNOS, and increase M2 type marker ARG, improving the neuroinflammation. TREM1 is a target for sevoflurane-induced PND prevention.


Assuntos
Inflamação , Microglia , Camundongos , Animais , Microglia/metabolismo , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Sevoflurano/efeitos adversos , Sevoflurano/metabolismo , Inflamação/metabolismo , Transtornos Neurocognitivos/metabolismo
18.
ACS Omega ; 8(17): 15479-15487, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151510

RESUMO

Efficient flotation of low-rank coal is of great significance for the development of green and low-carbon cycles. Temperature is a crucial parameter of flotation, but the mechanism of its effect on flotation lacks understanding. In this paper, the mechanism was studied by kinetic flotation, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, low-temperature liquid-nitrogen adsorption (LP-N2A), X-ray photoelectron spectroscopy (XPS), and molecular dynamics simulation. The flotation combustible recovery gradually decreases as temperature rises. Compared with 60 °C, the combustible recovery at 5 °C increases by 18.13%. The desorption energy for oil droplets decreases as the temperature rises. As a result, the oil droplets are easier to desorb at high temperatures. The SEM and LP-N2A results demonstrate that the pores and fractures of the coal sample are well developed. Also, the oil-water interfacial tension and viscosity of oil droplets decrease as the temperature rises, while the diffusion ability increases. These increase the volume of oil droplets that penetrate into the pores, resulting in poor spreadability of oil droplets on the coal surface. The average volume of bubbles gradually increases as temperature rises, which renders the flotation foam unstable and worsens the flotation. Therefore, the flotation performance is better at low temperatures.

19.
Curr Neurovasc Res ; 20(2): 207-217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37282646

RESUMO

BACKGROUND: To investigate the combined effect of red blood cell distribution width (RDW) and inflammatory biomarkers on in-hospital outcomes of acute ischemic stroke(AIS) patients with thrombolysis. METHODS: 417 AIS patients with thrombolysis were included. The participants were divided into four groups according to the cut-off of white blood cell (WBC) or C reactive protein (CRP) and RDW: LWLR, LWHR, HWLR, and HWHR; or LCLR, LCHR, HCLR, and HCHR (L-low, Hhigh, W-WBC, C-CRP, R-RDW). Logistic regression models were used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of in-hospital pneumonia and functional outcome across the four subgroups. RESULTS: Patients with higher RDW and inflammatory biomarkers levels have the highest risk of in-hospital outcomes. Compared with patients in the LWLR group, the ORs (95% CIs) of those in the HWHR group were 12.16 (4.21-35.14) and 9.31 (3.19-27.17) for in-hospital pneumonia and functional outcome. The ORs (95% CIs) of those in the HCHR group were 6.93 (2.70-17.78) and 3.38 (1.10-10.39) for in-hospital pneumonia and functional outcome, compared with patients in the LCLR group. Simultaneously adding RDW and WBC or CRP to the basic model with established risk factors significantly improved risk discrimination and reclassification for pneumonia and functional outcome (all p <0.05). CONCLUSIONS: Combined RDW and inflammatory biomarkers within 4.5 hours had a better predictive power for in-hospital outcomes of AIS patients with thrombolysis.


Assuntos
AVC Isquêmico , Pneumonia , Humanos , AVC Isquêmico/diagnóstico , AVC Isquêmico/tratamento farmacológico , Estudos Retrospectivos , Biomarcadores , Proteína C-Reativa/metabolismo , Hospitais , Eritrócitos/metabolismo , Terapia Trombolítica , Pneumonia/tratamento farmacológico , Prognóstico
20.
Front Aging Neurosci ; 15: 1238588, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37842121

RESUMO

Objective: The aim of this study was to explore the influential mechanism of the relationship between sleep quality and activities of daily living (ADL) in patients with Parkinson's disease (PD), we hypothesized disease severity as a mediator and assumed the mediating process was regulated by cognition. Methods: 194 individuals with PD (95 women and 99 men) were enrolled in study. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality of PD patients. Patients' ADL, disease severity and cognition were measured by the Unified Parkinson's Disease Rating Scale-II (UPDRSII), Hoehn-Yahr (H-Y) Scale, and Mini-Mental State Examination (MMSE). We investigated the mediating role of disease severity and the moderating effect of cognition on the association between sleep quality and ADL in PD patients. Results: The score of UPDRSII was positively correlated with the score of PSQI and H-Y stage, while the score of MMSE was negatively correlated with the score of H-Y stage and UPDRSII. Sleep quality predicts disease severity, and disease severity predicts ADL. Disease severity mediated the relationship between sleep quality and ADL, and the mediating effect was 0.179. Cognition alone did not affect ADL, but the interaction between disease severity and cognition was significantly affected ADL, confirming the moderating effect of cognition in PD patients. Conclusion: Disease severity mediated the association between sleep quality and ADL, good cognition significantly reduced disease severity's mediating influence on the relationship between sleep quality and ADL. Our study indicated a close relationship between ADL and sleep and cognition in PD, and also provided new insights into the overall management of PD and a better quality of life of PD patients.

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