RESUMO
Protein secretion and vacuole formation are vital processes in plant cells, playing crucial roles in various aspects of plant development, growth, and stress responses. Multiple regulators have been uncovered to be involved in these processes. In animal cells, the transcription factor TFEB has been extensively studied and its role in lysosomal biogenesis is well understood. However, the transcription factors governing protein secretion and vacuole formation in plants remain largely unexplored. In recent years, an increasing number of bioinformatics databases and tools have been developed, facilitating computational prediction and analysis of the function of genes or proteins in specific cellular processes. Leveraging these resources, this chapter aims to provide practical guidance on how to effectively utilize these existing databases and tools for the analysis of key transcription factors involved in regulating protein secretion and vacuole formation in plants, with a particular focus on Arabidopsis and other higher plants. The findings from this analysis can serve as a valuable resource for future experimental investigations and the development of targeted strategies to manipulate protein secretion and vacuole formation in plants.
Assuntos
Biologia Computacional , Fatores de Transcrição , Vacúolos , Vacúolos/metabolismo , Biologia Computacional/métodos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Transporte Proteico , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genéticaRESUMO
Initiation of flowering is a key switch for plants to shift from the vegetative growth to the phase of reproductive growth. This critical phase is essential not only for achieving successful reproduction, but also for facilitating environmental adaptation and maximizing yield potential. In the past decades, the environmental factors and genetic pathways that control flowering time have undergone extensive investigation in both model plant Arabidopsis and various crop species. The impact of environmental factors on plant flowering time is well documented. This paper focuses on the multilayered modulation of flowering time. Recent multi-omics approaches, and genetic screens have revealed additional components that modulate flowering time across various levels, encompassing chromatin modification, transcriptional and post-transcriptional control, as well as translational and post-translational regulation. The interplay between these various layers of regulation creates a finely-tuned system that can respond to a wide variety of inputs and allows plants to adjust flowering time in response to changing environmental conditions. In this review, we present a comprehensive overview of the recent progress made in understanding the intricate regulation of flowering time in plants, emphasizing the pivotal molecular components and their intricate interactions. Additionally, we provide an exhaustive list of key genes implicated in the intricate modulation of flowering time and offer a detailed summary of regulators of FLOWERING LOCUS T (FT) and FLOWERING LOCUS (FLC). We also discuss the implications of this knowledge for crop improvement and adaptation to changing environments.
Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismoRESUMO
Transcription factors play crucial roles in almost all physiological processes including leaf senescence. Cell death is a typical symptom appearing in senescing leaves, which is also classified as developmental programmed cell death (PCD). However, the link between PCD and leaf senescence still remains unclear. Here, we found a WRKY transcription factor WRKY47 positively modulates age-dependent leaf senescence in Arabidopsis (Arabidopsis thaliana). WRKY47 was expressed preferentially in senescing leaves. A subcellular localization assay indicated that WRKY47 was exclusively localized in nuclei. Overexpression of WRKY47 showed precocious leaf senescence, with less chlorophyll content and higher electrolyte leakage, but loss-of-function mutants of WRKY47 delayed this biological process. Through qRT-PCR and dual luciferase reporter assays, we found that WRKY47 could activate the expression of senescence-associated genes (SAGs) and PCD-associated genes to regulate leaf senescence. Furthermore, through electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-qPCR, WRKY47 was found to bind to W-box fragments in promoter regions of BFN1 (Bifunctional Nuclease 1) and MC6 (Metacaspase 6) directly. In general, our research revealed that WRKY47 regulates age-dependent leaf senescence by activating the transcription of two PCD-associated genes.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Senescência Vegetal , Fatores de Transcrição , Apoptose/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/genética , Senescência Vegetal/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Most pathogenic DMD variants are detectable and interpretable by standard genetic testing for dystrophinopthies. However, approximately 1â¼3% of dystrophinopthies patients still do not have a detectable DMD variant after standard genetic testing, most likely due to structural chromosome rearrangements and/or deep intronic pseudoexon-activating variants. Here, we report on a boy with a suspected diagnosis of Becker muscular dystrophy (BMD) who remained without a detectable DMD variant after exonic DNA-based standard genetic testing. Dystrophin mRNA studies and genomic Sanger sequencing were performed in the boy, followed by in silico splicing analyses. We successfully detected a novel deep intronic disease-causing variant in the DMD gene (c.2380 + 3317A > T), which consequently resulting in a new dystrophin pseudoexon activation through the enhancement of a cryptic donor splice site. The patient was therefore genetically diagnosed with BMD. Our case report further emphasizes the significant role of disease-causing splicing variants within deep intronic regions in genetically undiagnosed dystrophinopathies.
RESUMO
Potassium (K+), being an essential macronutrient in plants, plays a central role in many aspects. Root growth is highly plastic and is affected by many different abiotic stresses including nutrient deficiency. The Shaker-type K+ channel Arabidopsis (Arabidopsis thaliana) K+ Transporter 1 (AKT1) is responsible for K+ uptake under both low and high external K+ conditions. However, the upstream transcription factor of AKT1 is not clear. Here, we demonstrated that the WRKY6 transcription factor modulates root growth to low potassium (LK) stress in Arabidopsis. WRKY6 showed a quick response to LK stress and also to many other abiotic stress treatments. The two wrky6 T-DNA insertion mutants were highly sensitive to LK treatment, whose primary root lengths were much shorter, less biomass and lower K+ content in roots than those of wild-type plants, while WRKY6-overexpression lines showed opposite phenotypes. A further investigation showed that WRKY6 regulated the expression of the AKT1 gene via directly binding to the W-box elements in its promoter through EMSA and ChIP-qPCR assays. A dual luciferase reporter analysis further demonstrated that WRKY6 enhanced the transcription of AKT1. Genetic analysis further revealed that the overexpression of AKT1 greatly rescued the short root phenotype of the wrky6 mutant under LK stress, suggesting AKT1 is epistatic to WRKY6 in the control of LK response. Further transcriptome profiling suggested that WRKY6 modulates LK response through a complex regulatory network. Thus, this study unveils a transcription factor that modulates root growth under potassium deficiency conditions by affecting the potassium channel gene AKT1 expression.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Raízes de Plantas , Potássio , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Potássio/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Canais de PotássioRESUMO
RATIONALE: Ectopic ACTH-producing pituitary adenoma (EAPA) of the clivus region is extraordinarily infrequent condition and merely a few reports have been reported to date. PATIENT CONCERNS: The patient was a 53-year-old woman who presented with Cushing-like appearances and a soft tissue mass in the clivus region. DIAGNOSES: The final diagnosis of clivus region EAPA was established by clinical, radiological and histopathological findings. INTERVENTIONS: The patient underwent gross total clivus tumor resection via transsphenoidal endoscopy. OUTCOMES: Half a year after surgery, the patient Cushing-like clinical manifestations improved significantly, and urinary free cortisol and serum adrenocorticotropin (ACTH) returned to normal. LESSONS: Given the extreme scarcity of these tumors and their unique clinical presentations, it may be possible to misdiagnose and delayed treatment. Accordingly, it is especially crucial to summarize such lesions through our present case and review the literature for their precise diagnosis and the selection of optimal treatment strategies.
Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Síndrome de Cushing , Neoplasias Hipofisárias , Feminino , Humanos , Pessoa de Meia-Idade , Adenoma Hipofisário Secretor de ACT/complicações , Adenoma Hipofisário Secretor de ACT/diagnóstico , Adenoma Hipofisário Secretor de ACT/cirurgia , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/etiologia , Síndrome de Cushing/cirurgia , Adenoma/complicações , Adenoma/diagnóstico , Adenoma/cirurgia , Endoscopia/efeitos adversos , Imageamento por Ressonância Magnética/efeitos adversos , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/cirurgiaRESUMO
A magnetic chitosan/TiO2 composite material (MCT) was developed. MCT was successfully synthesized by a one-pot method using chitosan, TiO2, and Fe3O4. The absorption equilibrium time of MCT was 40 min in absorbing vanadium(v), the optimal adsorption pH was 4, and the maximum adsorption capacity of vanadium(v) was 117.1 mg g-1. The spent MCT was applied to photocatalytic reactions for reutilization. The decolorization rates for the degradation of rhodamine B (RhB) by new and spent MCT were 86.4% and 94.3%, respectively. The new and spent MCT exhibited absorption bands at 397 and 455 nm, respectively, which showed that the spent MCT was red-shifted to the cyan light region. These results indicated that the forbidden band widths of the new and spent MCT were about 3.12 and 2.72 eV, respectively. The mechanism of the degradation reaction showed that the hydroxyl radicals as oxidants in the spent MCT mediated the photocatalytic degradation of RhB. In addition, the superoxide anion radical formation of hydroxyl radicals was the main reaction, and the hole generation of hydroxyl radicals was the subordinate reaction. The N-de-ethylated intermediates and organic acids were monitored by MS and HPLC.
RESUMO
In plants, the endomembrane system is tightly regulated in response to environmental stresses for maintaining cellular homeostasis. Autophagosomes, the double membrane organelles forming upon nutrient deprivation or stress induction, degrade bulky cytosolic materials for nutrient turnover. Though abiotic stresses have been reported to induce plant autophagy, few receptors or regulators for selective autophagy have been characterized for specific stresses. Here, we have applied immunoprecipitation followed by tandem mass spectrometry using the autophagosome marker protein ATG8 as bait and have identified the E3 ligase of the ufmylation system Ufl1 as a bona fide ATG8 interactor under salt stress. Notably, core components in the ufmylation cascade, Ufl1 and Ufm1, interact with the autophagy kinase complexes proteins ATG1 and ATG6. Cellular and genetic analysis showed that Ufl1 is important for endoplasmic reticulum (ER)-phagy under persisting salt stress. Loss-of-function mutants of Ufl1 display a salt stress hypersensitive phenotype and abnormal ER morphology. Prolonged ER stress responses are detected in ufl1 mutants that phenocopy the autophagy dysfunction atg5 mutants. Consistently, expression of ufmylation cascade components is up-regulated by salt stress. Taken together, our study demonstrates the role of ufmylation in regulating ER homeostasis under salt stress through ER-phagy.
Assuntos
Arabidopsis , Arabidopsis/genética , Resposta a Proteínas não Dobradas , Estresse do Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/metabolismo , Autofagia/fisiologia , Estresse SalinoRESUMO
ADP-ribosylation factor (ARF) family proteins, one type of small guanine-nucleotide-binding (G) proteins, play a central role in regulating vesicular traffic and organelle structures in eukaryotes. The Arabidopsis (Arabidopsis thaliana) genome contains more than 21 ARF proteins, but relatively little is known about the functional heterogeneity of ARF homologs in plants. Here, we characterized the function of a unique ARF protein, ARFD1B, in Arabidopsis. ARFD1B exhibited both cytosol and punctate localization patterns, colocalizing with a Golgi marker in protoplasts and transgenic plants. Distinct from other ARF1 homologs, overexpression of a dominant-negative mutant form of ARFD1B did not alter the localization of the Golgi marker mannosidase I (ManI)-RFP in Arabidopsis cells. Interestingly, the ARFD1 artificial microRNA knockdown mutant arfd1 displayed a deleterious growth phenotype, while this phenotype was restored in complemented plants. Further, confocal imaging and transmission electron microscopy analyses of the arfd1 mutant revealed defective cell plate formation and abnormal Golgi morphology. Pull-down and liquid chromatography-tandem mass spectrometry analyses identified Coat Protein I (COPI) components as interacting partners of ARFD1B, and subsequent bimolecular fluorescence complementation, yeast (Saccharomyces cerevisiae) two-hybrid, and co-immunoprecipitation assays further confirmed these interactions. These results demonstrate that ARFD1 is required for cell plate formation, maintenance of Golgi morphology, and plant growth in Arabidopsis.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , MicroRNAs , Fator 1 de Ribosilação do ADP/metabolismo , Fatores de Ribosilação do ADP/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Complexo I de Proteína do Envoltório/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Complexo de Golgi/metabolismo , Guanina/metabolismo , MicroRNAs/metabolismo , Nucleotídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismoRESUMO
In eukaryotes, secretory proteins traffic from the endoplasmic reticulum (ER) to the Golgi apparatus via coat protein complex II (COPII) vesicles. Intriguingly, during nutrient starvation, the COPII machinery acts constructively as a membrane source for autophagosomes during autophagy to maintain cellular homeostasis by recycling intermediate metabolites. In higher plants, essential roles of autophagy have been implicated in plant development and stress responses. Nonetheless, the membrane sources of autophagosomes, especially the participation of the COPII machinery in the autophagic pathway and autophagosome biogenesis, remains elusive in plants. Here, we provided evidence in support of a novel role of a specific Sar1 homolog AtSar1d in plant autophagy in concert with a unique Rab1/Ypt1 homolog AtRabD2a. First, proteomic analysis of the plant ATG (autophagy-related gene) interactome uncovered the mechanistic connections between ATG machinery and specific COPII components including AtSar1d and Sec23s, while a dominant negative mutant of AtSar1d exhibited distinct inhibition on YFP-ATG8 vacuolar degradation upon autophagic induction. Second, a transfer DNA insertion mutant of AtSar1d displayed starvation-related phenotypes. Third, AtSar1d regulated autophagosome progression through specific recognition of ATG8e by a noncanonical motif. Fourth, we demonstrated that a plant-unique Rab1/Ypt1 homolog AtRabD2a coordinates with AtSar1d to function as the molecular switch in mediating the COPII functions in the autophagy pathway. AtRabD2a appears to be essential for bridging the specific AtSar1d-positive COPII vesicles to the autophagy initiation complex and therefore contributes to autophagosome formation in plants. Taken together, we identified a plant-specific nexus of AtSar1d-AtRabD2a in regulating autophagosome biogenesis.
Assuntos
Proteínas de Arabidopsis/metabolismo , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/metabolismo , Proteínas R-SNARE/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Autofagossomos/metabolismo , Autofagia/fisiologia , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/fisiologia , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Fagossomos/metabolismo , Transporte Proteico/fisiologia , Proteômica/métodos , Proteínas R-SNARE/fisiologia , Vacúolos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas rab de Ligação ao GTP/fisiologiaRESUMO
Plant flowering is crucial for the onset and progression of reproduction processes. The control of flowering time is a sophisticated system with multiple known regulatory mechanisms in plants. Here, we show that MYB117 participates in the flowering time regulation in Arabidopsis as myb117 mutants exhibited early flowering phenotypes under long-day condition. Transcriptome analysis of myb117 mutants revealed 410 differentially expressed genes between wild type and myb117-1 mutants, where selective genes including the Flowering Locus T (FT) were further confirmed by qRT-PCR analysis. Further, in vivo dual-luciferase and chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) assays showed that MYB117 directly binds to the promoter of FT to suppress its expression. Taken together, we have revealed the transcriptome profile of myb117 mutants and identified MYB117 as a negative regulator in controlling flowering time through regulating the expression of FT in Arabidopsis.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Flores/fisiologia , Fatores Genéricos de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Modelos Biológicos , Filogenia , Regiões Promotoras Genéticas , Ligação Proteica , Fatores de Tempo , Fatores Genéricos de Transcrição/genética , Transcrição GênicaRESUMO
Flowering time is crucial for successful reproduction in plants, the onset and progression of which are strictly controlled. However, flowering time is a complex and environmentally responsive history trait and the underlying mechanisms still need to be fully characterized. Post-translational regulation of the activities of transcription factors (TFs) is a dynamic and essential mechanism for plant growth and development. CRL3BPM E3 ligase is a CULLIN3-based E3 ligase involved in orchestrating protein stability via the ubiquitin proteasome pathway. Our study shows that the mutation of MYB106 induced early flowering phenotype while over-expression of MYB106 delayed Arabidopsis flowering. Transcriptome analysis of myb106 mutants reveals 257 differentially expressed genes between wild type and myb106-1 mutants, including Flowering Locus T (FT) which is related to flowering time. Moreover, in vitro electrophoretic mobility shift assays (EMSA), in vivo chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR) assays and dual luciferase assays demonstrate that MYB106 directly binds to the promoter of FT to suppress its expression. Furthermore, we confirm that MYB106 interacts with BPM proteins which are further identified by CRL3BPM E3 ligases as the substrate. Taken together, we have identified MYB106 as a negative regulator in the control of flowering time and a new substrate for CRL3BPM E3 ligases in Arabidopsis.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a life-threatening disease with a high mortality rate, which was a common complication of fat embolism syndrome (FES). Ursodeoxycholic acid (UDCA) has been reported to exert potent anti-inflammatory effects under various conditions. In vivo, perinephric fat was injected via tail vein to establish a rat FES model, the anti-inflammatory effects of UDCA on FES-induced lung injury were investigated through histological examination, ELISA, qRT-PCR, Western blot and immunofluorescence. In vitro, human lung microvascular endothelial cells (HPMECs) were employed to understand the protective effects of UDCA. The extent of ALI/ARDS was evaluated and validated by reduced PaO2 /FiO2 ratios, increased lung wet/dry (W/D) ratios and impaired alveolar-capillary barrier, up-regulation of ALI-related proteins in lung tissues (including myeloperoxidase [MPO], vascular cell adhesion molecule 1 [VCAM-1], intercellular cell adhesion molecule-1 [ICAM-1]), elevated protein concentration and increased proinflammatory cytokines levels (TNF-α and IL-1ß) in bronchoalveolar lavage fluid (BALF). Pre-treatment with UDCA remarkably alleviated these pathologic and biochemical changes of FES-induced ALI/ARDS; our data demonstrated that pre-treatment with UDCA attenuated the pathologic and biochemical changes of FES-induced ARDS, which provided a possible preventive therapy for lung injury caused by FES.
Assuntos
Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/prevenção & controle , Embolia Gordurosa/complicações , Substâncias Protetoras/farmacologia , Ácido Ursodesoxicólico/farmacologia , Lesão Pulmonar Aguda/patologia , Animais , Biomarcadores , Biópsia , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Imunofluorescência , Humanos , Imuno-Histoquímica , Masculino , Ratos , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/prevenção & controleRESUMO
Reactive oxygen species (ROS) and salicylic acid (SA) are two factors regulating leaf senescence and defense against pathogens. However, how a single gene integrates both ROS and SA pathways remains poorly understood. Here, we show that Arabidopsis WRKY55 transcription factor positively regulates ROS and SA accumulation, and thus leaf senescence and resistance against the bacterial pathogen Pseudomonas syringaeWRKY55 is predominantly expressed in senescent leaves and encodes a transcriptional activator localized to nuclei. Both inducible and constitutive overexpression of WRKY55 accelerates leaf senescence, whereas mutants delay it. Transcriptomic sequencing identified 1448 differentially expressed genes, of which 1157 genes are upregulated by WRKY55 expression. Accordingly, the ROS and SA contents in WRKY55-overexpressing plants are higher than those in control plants, whereas the opposite occurs in mutants. Moreover, WRKY55 positively regulates defense against P. syringae Finally, we show that WRKY55 activates the expression of RbohD, ICS1, PBS3 and SAG13 by binding directly to the W-box-containing fragments. Taken together, our work has identified a new WRKY transcription factor that integrates both ROS and SA pathways to regulate leaf senescence and pathogen resistance.
Assuntos
Proteínas de Arabidopsis/biossíntese , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/metabolismo , Fatores de Transcrição/biossíntese , Arabidopsis/genética , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Pseudomonas syringae , Fatores de Transcrição/genéticaRESUMO
Leaf senescence represents the final stage of leaf growth and development, and its onset and progression are strictly regulated; however, the underlying regulatory mechanisms remain largely unknown. In this study we found that WRKY42 was highly induced during leaf senescence. Loss-of-function wrky42 mutants showed delayed leaf senescence whereas the overexpression of WRKY42 accelerated senescence. Transcriptome analysis revealed 2721 differentially expressed genes between wild-type and WRKY42-overexpressing plants, including genes involved in salicylic acid (SA) and reactive oxygen species (ROS) synthesis as well as several senescence-associated genes (SAGs). Moreover, WRKY42 activated the transcription of isochorismate synthase 1 (ICS1), respiratory burst oxidase homolog F (RbohF) and a few SAG genes. Consistently, the expression of these genes was reduced in wrky42 mutants but was markedly increased in transgenic Arabidopsis overexpressing WRKY42. Both in vitro electrophoretic mobility shift assays (EMSAs) and in vivo chromatin immunoprecipitation and dual luciferase assays demonstrated that WRKY42 directly bound to the promoters of ICS1 and RbohF, as well as a few SAGs, to activate their expression. Genetic analysis further showed that mutations of ICS1 and RbohF suppressed the early senescence phenotype evoked by WRKY42 overexpression. Thus, we have identified WRKY42 as a novel transcription factor positively regulating leaf senescence by directly activating the transcription of ICS1, RbohF and SAGs, without any seed yield penalty.
Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/metabolismo , Fatores de Transcrição/fisiologia , Envelhecimento/genética , Envelhecimento/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/fisiologia , Folhas de Planta/fisiologia , Fatores de Transcrição/metabolismoRESUMO
Salicylic acid (SA) and reactive oxygen species (ROS) are two well-defined inducers of leaf senescence. Here, we identified a novel WRKY transcription factor gene WSR1 (WRKY regulating SA and ROS 1) in Brassica napus (rapeseed) in promoting SA and ROS production, which eventually led to leaf senescence thereafter. Its expression increased in senescing leaves. Ca2+-dependent protein kinase (CPK) 5 and -6 interacted with and phosphorylated BnaWSR1. Overexpression of phosphomimic BnaWSR1 (BnaWSR1ca) in rapeseed protoplasts elicited ROS production and cell death while its ectopic expression in Arabidopsis enhanced SA and ROS levels and, hence, accelerated leaf senescence. Furthermore, BnaWSR1ca activated the expression of Isochorismate Synthase 1 (ICS1), Respiratory Burst Oxidase Homologue (Rboh) D, and Senescence-Associated Gene 14 (SAG14). Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) assays demonstrated that BnaWSR1ca directly bound to promoter regions of ICS1, RbohD, and SAG14. These data have identified a CPK-WSR1 module that integrates SA and ROS to control cell death and leaf senescence.
Assuntos
Brassica napus/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/metabolismo , Fatores de Transcrição/metabolismo , Brassica napus/genética , Senescência Celular , Regulação da Expressão Gênica de Plantas , Fosforilação , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas Quinases/genética , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: To evaluate whether the level of myeloid-derived suppressor cells is related to the complication of sepsis after esophageal cancer surgery and whether changing the myeloid-derived suppressor cells levels can improve the prognosis of patients cancer-related sepsis. METHODS: A total of 178 esophageal cancer patients from Harbin Medical University Cancer Hospital were included in this study. Blood samples were taken from the patients for the analysis of the levels of G-MDSCs and M-MDSCs by flow cytometry. The conditions of the patients was recorded. Male C57BL/6 mice were implanted with Lewis lung cancer cells (2 × 106/mice) by subcutaneous injection into the iliac fossa. Three weeks later, we performed CLP in the mice. All-trans-retinoic acid (ATRA) was intraperitoneally injected at 20 mg/kg, and the control group was injected with 0.9 % NS. We observed the mortality of the mice with cancer-related sepsis. RESULTS: In all, 95 % of the esophageal cancer patients had a high level of G-MDSCs (>50 %). A high level of G-MDSCs (>82.5 %) can lead to high morbidity from sepsis after surgery. The increase in M-MDSCs was suggestive of a poor prognosis in patients with cancer-related sepsis. ATRA can improve the survival of patients with cancer-related sepsis. CONCLUSIONS: A high level of G-MDSCs can be used to determine the incidence of sepsis in preoperative esophageal cancer patients, M-MDSCs might be effective prognostic indicators for cancer-sepsis patients, and changing the MDSC levels can improve the mortality of patients with cancer-related sepsis.
Assuntos
Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/complicações , Contagem de Leucócitos , Células Supressoras Mieloides/metabolismo , Sepse/etiologia , Idoso , Animais , Biomarcadores , Modelos Animais de Doenças , Suscetibilidade a Doenças , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/cirurgia , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Masculino , Camundongos , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Fatores de Risco , Sepse/diagnóstico , Sepse/mortalidade , Análise de SobrevidaRESUMO
OBJECTIVE: To investigate the protective effects of curcumin on LPS-induced septic acute kidney injury and to explore its underlying molecular mechanisms. METHODS: A mouse model of septic acute kidney injury (AKI) was given an intraperitoneal injection of lipopolysaccharide (LPS), followed by administration of variable levels of curcumin (intragastric). And NRK cells were used as the kidney cell model for all in vitro studies. RESULTS: Curcumin significantly decreased the levels of serum Scr, BUN, and Cyc c and reduced kidney injury in LPS-induced AKI mice. Kidney tissues of LPS-induced AKI mice showed an increase in PVT1, ED-1, TNF-α, IL-1ß, IL-6, p-IkBα/IkBα, p-p65/p65, p-JNK/JNK, and p-c-JUN/c-JUN expression levels; however, treatment with curcumin significantly reduced this effect. Curcumin increased the survival rate NRK cells exposed to LPS-induced inflammation in vitro. Moreover, NRK cells that overexpressed PVT1 had lower survival rates than WT NRK cells obtained from mice that received curcumin treatment after treating with LPS. Additionally, curcumin reduced the LPS-induced increase in Bax, cleaved-caspase3/caspase 3, p-IkBα/IkBα, p-p65/p65, p-JNK/JNK, and p-c-JUN/c-JUN protein expression, and increased Bcl2 protein expression in NRK cells. However, the extent of these changes was low in NRK cells that overexpressed PVT1. CONCLUSION: Curcumin decreased PVT1 expression in LPS-induced septic acute kidney tissues and reduced LPS-induced septic acute kidney injury in mice. This might be related to the inhibition of the JNK/NF-κB pathway by curcumin through suppression of lncRNA PVT1.
Assuntos
Injúria Renal Aguda/induzido quimicamente , Curcumina/farmacologia , Lipopolissacarídeos/toxicidade , Sepse/induzido quimicamente , Animais , Linhagem Celular , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
OBJECTIVES: The aim of this study was to identify the prevalence of peripherally inserted central catheter (PICC) malposition and the influence of guide wire removal on tip location in PICCs and determine whether related factors, including age, sex, side of insertion and brand of catheter, influence the PICC tip location. SETTING: Single-centre research institute in China recruiting patients from the hospital. PARTICIPANTS: A total of 837 adult patients with inserted PICCs were recruited from October 2016 to May 2017. INTERVENTIONS: This was a cross-sectional study aiming to identify the prevalence of PICC malposition and the influence of guide wire removal on tip location in PICCs. A linear regression model and a variance of factorial design analysis were performed. The PICC tip location was documented on a postinsertion chest X-ray. Multivariable analyses were performed based on the following related factors: age, sex, side of insertion and brand of catheter. RESULTS: The tip location moved a mean of 17.4 mm among the 837 included patients. The prevalence of PICC malposition was 83.6% (700/837), while 16.4% (137/837) of PICCs remained in correct location. The mean movement caused by guide wire removal without an adjusted tail end was (-1.95±26.90) mm. The difference between tail end adjustment movement and actual tip position movement in each PICC was (33.0±17.1) mm in type C, which was significantly higher than the findings for type A (12.8±13.3) mm and type B (12.9±12.7) mm. CONCLUSIONS: PICC malposition is a frequent event. Different catheter brands were associated with different ranges of movement in tip location after guide wire removal. The age and sex of the patients and the insertion side did not influence the extent of movement.
Assuntos
Cateterismo Periférico/métodos , Cateteres Venosos Centrais/estatística & dados numéricos , Átrios do Coração , Falha de Prótese , Veia Cava Superior , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
This study aims to examine the impact of ursodeoxycholic acid (UDCA) on pulmonary edema and explore the underlying molecular mechanisms. The effects of UDCA on pulmonary edema were assessed through hematoxylin and eosin (H&E) staining, lung dry/wet (W/D) ratio, TNF-α/IL-1ß levels of bronchoalveolar lavage fluid (BALF), protein expression of epithelial sodium channel (ENaC), and Na+ /K+ -ATPase. Besides, the detailed mechanisms were explored in primary rat alveolar type (AT) II epithelial cells by determining the effects of BOC-2 (ALX [lipoxin A4 receptor] inhibitor), Rp-cAMP (cAMP inhibitor), LY294002 (PI3K inhibitor), and H89 (PKA inhibitor) on the therapeutic effects of UDCA against lipopolysaccharide (LPS)-induced changes. Histological examination suggested that LPS-induced lung injury was obviously attenuated by UDCA. BALF TNF-α/IL-1ß levels and lung W/D ratios were decreased by UDCA in LPS model rats. UDCA stimulated alveolar fluid clearance (AFC) though the upregulation of ENaC and Na+ /K+ -ATPase. BOC-2, Rp-cAMP, and LY294002 largely suppressed the therapeutic effects of UDCA. Significant attenuation of pulmonary edema and lung inflammation was revealed in LPS-challenged rats after the UDCA treatment. The therapeutic efficacy of UDCA against LPS was mainly achieved through the ALX/cAMP/PI3K pathway. Our results suggested that UDCA might be a potential drug for the treatment of pulmonary edema induced by LPS.