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1.
Nature ; 631(8020): 393-401, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38776962

RESUMO

AMPylation is a post-translational modification in which AMP is added to the amino acid side chains of proteins1,2. Here we show that, with ATP as the ligand and actin as the host activator, the effector protein LnaB of Legionella pneumophila exhibits AMPylase activity towards the phosphoryl group of phosphoribose on PRR42-Ub that is generated by the SidE family of effectors, and deubiquitinases DupA and DupB in an E1- and E2-independent ubiquitination process3-7. The product of LnaB is further hydrolysed by an ADP-ribosylhydrolase, MavL, to Ub, thereby preventing the accumulation of PRR42-Ub and ADPRR42-Ub and protecting canonical ubiquitination in host cells. LnaB represents a large family of AMPylases that adopt a common structural fold, distinct from those of the previously known AMPylases, and LnaB homologues are found in more than 20 species of bacterial pathogens. Moreover, LnaB also exhibits robust phosphoryl AMPylase activity towards phosphorylated residues and produces unique ADPylation modifications in proteins. During infection, LnaB AMPylates the conserved phosphorylated tyrosine residues in the activation loop of the Src family of kinases8,9, which dampens downstream phosphorylation signalling in the host. Structural studies reveal the actin-dependent activation and catalytic mechanisms of the LnaB family of AMPylases. This study identifies, to our knowledge, an unprecedented molecular regulation mechanism in bacterial pathogenesis and protein phosphorylation.


Assuntos
Monofosfato de Adenosina , Proteínas de Bactérias , Legionella pneumophila , Fosfotirosina , Transdução de Sinais , Humanos , Actinas/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , ADP-Ribosilação , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Hidrólise , Legionella pneumophila/enzimologia , Legionella pneumophila/metabolismo , Legionella pneumophila/patogenicidade , Ligantes , Modelos Moleculares , N-Glicosil Hidrolases/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Tirosina/metabolismo , Tirosina/química , Ubiquitina/metabolismo , Ubiquitinação , Enzimas Desubiquitinantes/metabolismo , Dobramento de Proteína , Fosfotirosina/química , Fosfotirosina/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(15): e2313903121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557178

RESUMO

Electromagnetic radiation (EMR) in the environment, particularly in the microwave range, may constitute a public health concern. Exposure to 2.4 GHz EMR modulated by 100 Hz square pulses was recently reported to markedly increase wakefulness in mice. Here, we demonstrate that a similar wakefulness increase can be induced by the modulation frequency of 1,000 Hz, but not 10 Hz. In contrast to the carrier frequency of 2.4 GHz, 935 MHz EMR of the same power density has little impact on wakefulness irrespective of modulation frequency. Notably, the replacement of the 100 Hz square-pulsed modulation by sinusoidal-pulsed modulation of 2.4 GHz EMR still allows a marked increase of wakefulness. In contrast, continuous sinusoidal amplitude modulation of 100 Hz with the same time-averaged power output fails to trigger any detectable change of wakefulness. Therefore, alteration of sleep behavior by EMR depends upon not just carrier frequency but also frequency and mode of the modulation. These results implicate biological sensing mechanisms for specific EMR in animals.


Assuntos
Radiação Eletromagnética , Vigília , Camundongos , Animais , Campos Eletromagnéticos
3.
Plant J ; 119(4): 1859-1879, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923625

RESUMO

In the field, necrosis area induced by pathogens is usually surrounded by a red circle in apple fruits. However, the underlying molecular mechanism of this phenomenon remains unclear. In this study, we demonstrated that accumulated salicylic acid (SA) induced by fungal infection promoted anthocyanin biosynthesis through MdNPR1-MdTGA2.2 module in apple (Malus domestica). Inoculating apple fruits with Valsa mali or Botryosphaeria dothidea induced a red circle surrounding the necrosis area, which mimicked the phenotype observed in the field. The red circle accumulated a high level of anthocyanins, which was positively correlated with SA accumulation stimulated by fungal invasion. Further analysis showed that SA promoted anthocyanin biosynthesis in a dose-dependent manner in both apple calli and fruits. We next demonstrated that MdNPR1, a master regulator of SA signaling, positively regulated anthocyanin biosynthesis in both apple and Arabidopsis. Moreover, MdNPR1 functioned as a co-activator to interact with and enhance the transactivation activity of MdTGA2.2, which could directly bind to the promoters of anthocyanin biosynthetic and regulatory genes to promote their transcription. Suppressing expression of either MdNPR1 or MdTGA2.2 inhibited coloration of apple fruits, while overexpressing either of them significantly promoted fruit coloration. Finally, we revealed that silencing either MdNPR1 or MdTGA2.2 in apple fruits repressed SA-induced fruit coloration. Therefore, our data determined that fungal-induced SA promoted anthocyanin biosynthesis through MdNPR1-MdTGA2.2 module, resulting in a red circle surrounding the necrosis area in apple fruits.


Assuntos
Antocianinas , Ascomicetos , Frutas , Regulação da Expressão Gênica de Plantas , Malus , Doenças das Plantas , Proteínas de Plantas , Ácido Salicílico , Malus/microbiologia , Malus/genética , Malus/metabolismo , Ácido Salicílico/metabolismo , Antocianinas/biossíntese , Antocianinas/metabolismo , Ascomicetos/fisiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/microbiologia , Frutas/metabolismo , Frutas/genética , Arabidopsis/microbiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
5.
Mol Ther ; 32(3): 766-782, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38273656

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic lethal disease in the absence of demonstrated efficacy for preventing progression. Although macrophage-mediated alveolitis is determined to participate in myofibrotic transition during disease development, the paradigm of continuous macrophage polarization is still under-explored due to lack of proper animal models. Here, by integrating 2.5 U/kg intratracheal Bleomycin administration and 10 Gy thorax irradiation at day 7, we generated a murine model with continuous alveolitis-mediated fibrosis, which mimics most of the clinical features of our involved IPF patients. In combination with data from scRNA-seq of patients and a murine IPF model, a decisive role of CCL2/CCR2 axis in driving M1 macrophage polarization was revealed, and M1 macrophage was further confirmed to boost alveolitis in leading myofibroblast activation. Multiple sticky-end tetrahedral framework nucleic acids conjunct with quadruple ccr2-siRNA (FNA-siCCR2) was synthesized in targeting M1 macrophages. FNA-siCCR2 successfully blocked macrophage accumulation in pulmonary parenchyma of the IPF murine model, thus preventing myofibroblast activation and leading to the disease remitting. Overall, our studies lay the groundwork to develop a novel IPF murine model, reveal M1 macrophages as potential therapeutic targets, and establish new treatment strategy by using FNA-siCCR2, which are highly relevant to clinical scenarios and translational research in the field of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Macrófagos , Humanos , Camundongos , Animais , Modelos Animais de Doenças , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose , DNA , Bleomicina
6.
Biochemistry ; 63(7): 855-864, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498694

RESUMO

AQP4-IgG is an autoantibody associated with neuromyelitis optica spectroscopic disorder (NMOSD), a central nervous system inflammatory disease that requires early diagnosis and treatment. We designed two fusion proteins, AQP4-DARPin1 and AQP4-DARPin2, comprising the complete antigenic epitopes of aquaporin-4 (AQP4) and the constant region of the scaffold protein DARPin. These fusion proteins were expressed and purified from Escherichia coli and coated on microplates to develop an efficient method for detecting AQP4-IgG. Molecular dynamics simulation revealed that the fusion of AQP4 extracellular epitopes with DARPin did not alter the main structure of DARPin. The purified AQP4-DARPins bound recombinant antibody rAb-53 (AQP4-IgG) with affinities of 135 and 285 nM, respectively. Enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation demonstrated that AQP4-DARPin1 specifically recognized AQP4-IgG in the NMOSD patient serum. AQP4-DARPin1 as a coated antigen showed higher ELISA signal and end point dilution ratio than full-length AQP4. Our AQP4-DARPin1-coated AQP4-IgG ELISA had 100% specificity and 90% sensitivity. These results indicate that AQP4-DARPin1, compared to existing detection strategies that use full-length or extracellular loop peptides of AQP4, provides a new and more effective approach to the ELISA detection of NMOSD.


Assuntos
Neuromielite Óptica , Humanos , Neuromielite Óptica/diagnóstico , Proteínas de Repetição de Anquirina Projetadas , Aquaporina 4/genética , Epitopos , Imunoglobulina G
7.
Plant Mol Biol ; 114(3): 46, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630415

RESUMO

Peach fruit rapidly soften after harvest, a significant challenge for producers and marketers as it results in rotting fruit and significantly reduces shelf life. In this study, we identified two tandem genes, PpNAC1 and PpNAC5, within the sr (slow ripening) locus. Phylogenetic analysis showed that NAC1 and NAC5 are highly conserved in dicots and that PpNAC1 is the orthologous gene of Non-ripening (NOR) in tomato. PpNAC1 and PpNAC5 were highly expressed in peach fruit, with their transcript levels up-regulated at the onset of ripening. Yeast two-hybrid and bimolecular fluorescence complementation assays showed PpNAC1 interacting with PpNAC5 and this interaction occurs with the tomato and apple orthologues. Transient gene silencing experiments showed that PpNAC1 and PpNAC5 positively regulate peach fruit softening. Yeast one-hybrid and dual luciferase assays and LUC bioluminescence imaging proved that PpNAC1 and PpNAC5 directly bind to the PpPGF promoter and activate its transcription. Co-expression of PpNAC1 and PpNAC5 showed higher levels of PpPGF activation than expression of PpNAC1 or PpNAC5 alone. In summary, our findings demonstrate that the tandem transcription factors PpNAC1 and PpNAC5 synergistically activate the transcription of PpPGF to regulate fruit softening during peach fruit ripening.


Assuntos
Prunus persica , Solanum lycopersicum , Prunus persica/genética , Frutas/genética , Filogenia , Saccharomyces cerevisiae , Solanum lycopersicum/genética , Fatores de Transcrição/genética
8.
Int J Cancer ; 155(4): 756-765, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38693790

RESUMO

Breast cancer (BC) is a complex disease with diverse manifestations, often resulting in lymph node metastasis (LNM) and impacting patient prognosis. Extrachromosomal circular DNA (eccDNA) has emerged as a key player in tumorigenesis, yet its contribution to BC LNM remains elusive. Here, we examined primary tumors and matched LNM tissues from 19 BC patients using the Circle-Seq method. We identified a median count of 44,682 eccDNA in primary tumor tissues and 38,057 in their paired LNM tissues. Furthermore, a ladder-like size distribution is observed in both primary tumor and LNM tissues. Meanwhile, similar repeat sequence distribution and GC content are identified from both primary tissue and LNM tissues. Finally, we found that eccDNA from both groups are flanked with palindromic trinucleotide motifs. These observations indicate that eccDNA of primary tumor and LNM tissues are from similar chromosomal origins. However, a subset of miRNA-associated eccDNA displayed selective enrichment in metastatic lesions, such as miR-6730 and miR-548AA1 genes. This observation implicates the function of miRNA-related eccDNA in the metastatic cascade. Our study uncovers the potential significance of these unique eccDNA molecules, shedding light on their role in cancer metastasis.


Assuntos
Neoplasias da Mama , DNA Circular , Metástase Linfática , MicroRNAs , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Metástase Linfática/genética , DNA Circular/genética , MicroRNAs/genética , Pessoa de Meia-Idade , Linfonodos/patologia , Idoso
9.
Anal Chem ; 96(10): 3989-3993, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38315070

RESUMO

The nanoelectrosprayer is a key device in the hyphenation of nanoLC-ESI-MS, and its development plays a crucial role in pushing forward the mining depth of biological discovery and industrialization of omics science. In this work, a new type of nanoelectrospray emitter, a rod sprayer, was developed based on microfluidic manufacture. Due to its porous silica structure, the rod sprayer in effect worked as a multinozzle sprayer, which is composed of a bunch of micrometer sized spray channels. Without the need for sophisticated microfabrication equipment, a superclean environment, or a complicated assembling process, such sprayer rods can be facilely fabricated in a mass production style: 3,600 rods with excellent monodispersity have been fabricated in 1 h, and rod sprayers thus made have demonstrated excellent intraday, interday, and interbatch reproducibilities: RSD = 1.9, 4.9, and 6.1%, respectively. The rod sprayer can generate stable electrospray in a wide voltage range from 2.6 to 3.2 kV and flow rates from 50 to 1000 nL/min, covering typical flow rates of subnanoLC, nanoLC, to microLC, and work steadily even under complex matrix environments (e.g., Hank's balanced salt solution containing sodium, magnesium, and calcium ions) without clogging. Meanwhile, the rod sprayers exhibited 200-1800% ionization efficiency enhancement in comparison with commonly used tapered tip emitters, for small molecule drugs, peptides, and proteins, respectively, and provided a broadened linear dynamic range of 4 orders of magnitude. The excellent characteristics of the rod sprayer, together with its small size and mass production capacity, should provide a high quality, high durability, high consistency, and disposable use-supported nanoelectrospray solution for MS-based bioanalyses.

10.
BMC Med ; 22(1): 192, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38735950

RESUMO

BACKGROUND: Peripheral glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) are sensitive markers of neuroinflammation and neuronal damage. Previous studies with highly selected participants have shown that peripheral GFAP and NfL levels are elevated in the pre-clinical phase of Alzheimer's disease (AD) and dementia. However, the predictive value of GFAP and NfL for dementia requires more evidence from population-based cohorts. METHODS: This was a prospective cohort study to evaluate UK Biobank participants enrolled from 2006 to 2010 using plasma GFAP and NfL measurements measured by Olink Target Platform and prospectively followed up for dementia diagnosis. Primary outcome was the risk of clinical diagnosed dementia. Secondary outcomes were cognition. Linear regression was used to assess the associations between peripheral GFAP and NfL with cognition. Cox proportional hazard models with cross-validations were used to estimate associations between elevated GFAP and NfL with risk of dementia. All models were adjusted for covariates. RESULTS: A subsample of 48,542 participants in the UK Biobank with peripheral GFAP and NfL measurements were evaluated. With an average follow-up of 13.18 ± 2.42 years, 1312 new all-cause dementia cases were identified. Peripheral GFAP and NfL increased up to 15 years before dementia diagnosis was made. After strictly adjusting for confounders, increment in NfL was found to be associated with decreased numeric memory and prolonged reaction time. A greater annualized rate of change in GFAP was significantly associated with faster global cognitive decline. Elevation of GFAP (hazard ratio (HR) ranges from 2.25 to 3.15) and NfL (HR ranges from 1.98 to 4.23) increased the risk for several types of dementia. GFAP and NfL significantly improved the predictive values for dementia using previous models (area under the curve (AUC) ranges from 0.80 to 0.89, C-index ranges from 0.86 to 0.91). The AD genetic risk score and number of APOE*E4 alleles strongly correlated with GFAP and NfL levels. CONCLUSIONS: These results suggest that peripheral GFAP and NfL are potential biomarkers for the early diagnosis of dementia. In addition, anti-inflammatory therapies in the initial stages of dementia may have potential benefits.


Assuntos
Demência , Proteína Glial Fibrilar Ácida , Proteínas de Neurofilamentos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Demência/sangue , Demência/diagnóstico , Demência/epidemiologia , Proteína Glial Fibrilar Ácida/sangue , Estudos Longitudinais , Proteínas de Neurofilamentos/sangue , Estudos Prospectivos , Biobanco do Reino Unido , Reino Unido/epidemiologia
11.
J Mol Recognit ; 37(2): e3071, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38167828

RESUMO

Cancer is associated with the highest mortality rate globally. While life-saving screening and treatments exist, better awareness is needed. RNF187, an E3 ligase regulating biological processes, belongs to the RING domain-containing E3 ligase family. RNF187 may serve as an oncogene due to abnormal expression in tumors. However, its association with immune infiltration and prognosis across various cancers remains unclear. We searched several databases including TCGA, GTE x, CCLE, TIMER, and GSEA. R software was used to evaluate RNF187 differential expression, survival, pathology stage, DNA methylation, tumor mutational burden (TMB), microsatellite instability (MSI), gene co-expression analysis, mismatch repairs (MMRs), tumor microenvironment (TME), and immune cell infiltration. Clinicopathological data were collected, and immunohistochemistry was used to verify RNF187 expression in tumor tissues. RNF187 expression was up-regulated in various cancers compared to that in normal tissues and associated with poor patient outcomes. Dysregulation of RNF187 expression in multiple cancer types was strongly correlated with DNA methylation, MMR, MSI, and TMB. RNF187 could interact with different immune cells in cancers. Biomarkers associated with RNF187 may be helpful for prognosis and immunology in treating pan-cancer patients.


Assuntos
Biomarcadores Tumorais , Neoplasias , Humanos , Biomarcadores Tumorais/genética , Prognóstico , Neoplasias/diagnóstico , Neoplasias/genética , Software , Ubiquitina-Proteína Ligases/genética , Microambiente Tumoral/genética , Transativadores
12.
Planta ; 259(6): 125, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634979

RESUMO

MAIN CONCLUSION: Overexpression of MdLBD3 in Arabidopsis reduced sensitivity to salt and drought stresses and was instrumental in promoting early flowering. Salt and drought stresses have serious effects on plant growth. LATERAL ORGAN BOUNDARY DOMAIN (LBD) proteins are a plant-specific transcription factors (TFs) family and play important roles in plants in resisting to abiotic stress. However, about the function of LBDs in apple and other woody plants is little known. In this study, protein sequences of the LBD family TFs in apples were identified which contained conserved LOB domains. The qRT-PCR analysis showed that the MdLBD3 gene was widely expressed in various tissues and organs. The subcellular localization assay showed that the MdLBD3 protein was localized in the nucleus. Ectopic expression of MdLBD3 in Arabidopsis positively regulated its salt and drought resistance, and promoted early flowering. Collectively, these results showed that MdLBD3 improved the abiotic stress resistance, plant growth and development. Overall, this study provided a new gene for breeding that can increase the abiotic stress tolerance in apple.


Assuntos
Arabidopsis , Malus , Fatores de Transcrição , Secas , Melhoramento Vegetal , Estresse Salino , Clonagem Molecular
13.
J Transl Med ; 22(1): 83, 2024 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245759

RESUMO

BACKGROUND: Observational studies have suggested an association between multiple sclerosis (MS) and cortical structure, but the results have been inconsistent. OBJECTIVE: We used two-sample Mendelian randomization (MR) to assess the causal relationship between MS and cortical structure. METHODS: MS data as the exposure trait, including 14,498 cases and 24,091 controls, were obtained from the International Multiple Sclerosis Genetics Consortium. Genome-wide association study (GWAS) data for cortical surface area (SAw/nw) and thickness (THw/nw) in 51,665 individuals of European ancestry were obtained from the ENIGMA Consortium. The inverse-variance weighted (IVW) method was used as the primary analysis for MR. Sensitivity analyses were conducted to evaluate heterogeneity and pleiotropy. Enrichment analysis was performed on MR analyses filtered by sensitivity analysis. RESULTS: After IVW and sensitivity analysis filtering, only six surviving MR results provided suggestive evidence supporting a causal relationship between MS and cortical structure, including lingual SAw (p = .0342, beta (se) = 5.7127 (2.6969)), parahippocampal SAw (p = .0224, beta (se) = 1.5577 (0.6822)), rostral middle frontal SAw (p = .0154, beta (se) = - 9.0301 (3.7281)), cuneus THw (p = .0418, beta (se) = - 0.0020 (0.0010)), lateral orbitofrontal THw (p = .0281, beta (se) = 0.0025 (0.0010)), and lateral orbitofrontal THnw (p = .0417, beta (se) = 0.0029 (0.0014)). Enrichment analysis suggested that leukocyte cell-related pathways, JAK-STAT signaling pathway, NF-kappa B signaling pathway, cytokine-cytokine receptor interaction, and prolactin signaling pathway may be involved in the effect of MS on cortical morphology. CONCLUSION: Our results provide evidence supporting a causal relationship between MS and cortical structure. Enrichment analysis suggests that the pathways mediating brain morphology abnormalities in MS patients are mainly related to immune and inflammation-driven pathways.


Assuntos
Encefalopatias , Esclerose Múltipla , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Esclerose Múltipla/genética , Causalidade , Receptores de Citocinas , Polimorfismo de Nucleotídeo Único/genética
14.
J Bioenerg Biomembr ; 56(4): 433-449, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38825632

RESUMO

Energy metabolism has always been a hot topic in cancer progression and targeted therapy, and exploring the role of genes in energy metabolic pathways in cancer cells has become key to address this issue. Eukaryotic translation initiation factor 2α kinase 2 (EIF2AK2) plays regulatory roles in cancer and disorders of energy metabolism. Indeed, the role of EIF2AK2 in energy metabolism has been underestimated. The aim of this study is to reveal the expression specificity of EIF2AK2 in gastric cancer (GC) progression and metastasis, and to demonstrate the role of EIF2AK2 in energy metabolism, cytoskeleton, proliferation, death and metastasis pathways in GC cells. Mechanistically, EIF2AK2 overexpression promoted cytoskeleton remodeling and ATP production, mediated cell proliferation and metastasis, upregulated OAS1 expression, decreases p-AMPK expression and inhibited apoptosis in GC cells. Conversely, knockdown of EIF2AK2 resulted in the opposite effect. However, overexpression of OAS1 mediated the upregulation of mitochondrial membrane potential and promoted ATP production and NAD+/NADH ratio, but knockdown of OAS1 inhibited the above effects. In addition, knockdown of OAS1 had no effect on EIF2AK2 expression, but inhibited AMPK and upregulated p-AMPK expression. In conclusion, our study identified EIF2AK2 and OAS1 as previously undescribed regulators of energy metabolism in GC cells. We hypothesized that EIF2AK2-OAS1 axis may regulate energy metabolism and inhibit cellular malignant behavior in cancer cells by affecting ATP production to induce AMPK phosphorylation, suggesting EIF2AK2 as a potential therapeutic target for cancer cell progression.


Assuntos
Proteínas Quinases Ativadas por AMP , Trifosfato de Adenosina , Neoplasias Gástricas , eIF-2 Quinase , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Humanos , Trifosfato de Adenosina/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , eIF-2 Quinase/metabolismo , Fosforilação , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes
15.
Plant Cell Environ ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39049759

RESUMO

Fruit colour is a critical determinant for the appearance quality and commercial value of apple fruits. Viroid-induced dapple symptom severely affects the fruit coloration, however, the underlying mechanism remains unknown. In this study, we identified an apple dimple fruit viroid (ADFVd)-derived small interfering RNA, named vsiR693, which targeted the mRNA coding for a bHLH transcription factor MdPIF1 (PHYTOCHROME-INTERACTING FACTOR 1) to regulate anthocyanin biosynthesis in apple. 5' RLM-RACE and artificial microRNA transient expression system proved that vsiR693 directly targeted the mRNA of MdPIF1 for cleavage. MdPIF1 positively regulated anthocyanin biosynthesis in both apple calli and fruits, and it directly bound to G-box element in the promoter of MdPAL and MdF3H, two anthocyanin biosynthetic genes, to promote their transcription. Expression of vsiR693 negatively regulated anthocyanin biosynthesis in both apple calli and fruits. Furthermore, co-expression of vsiR693 and MdPIF1 suppressed MdPIF1-promoted anthocyanin biosynthesis in apple fruits. Infiltration of ADFVd infectious clone suppressed coloration surrounding the injection sites in apple fruits, while a mutated version of ADFVd, in which the vsiR693 producing region was mutated, failed to repress fruit coloration around the injection sites. These data provide evidence that a viroid-derived small interfering RNA targets host transcription factor to regulate anthocyanin biosynthesis in apple.

16.
Plant Cell Environ ; 47(5): 1668-1684, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38282271

RESUMO

Drought stress is one of the main environmental factors limiting plant growth and development. Plants adapt to changing soil moisture by modifying root architecture, inducing stomatal closure, and inhibiting shoot growth. The AP2/ERF transcription factor DREB2A plays a key role in maintaining plant growth in response to drought stress, but the molecular mechanism underlying this process remains to be elucidated. Here, it was found that overexpression of MdDREB2A positively regulated nitrogen utilisation by interacting with DRE cis-elements of the MdNIR1 promoter. Meanwhile, MdDREB2A could also directly bind to the promoter of MdSWEET12, which may enhance root development and nitrogen assimilation, ultimately promoting plant growth. Overall, this regulatory mechanism provides an idea for plants in coordinating with drought tolerance and nitrogen assimilation to maintain optimal plant growth and development under drought stress.


Assuntos
Secas , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas , Sacarose/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética
17.
Opt Lett ; 49(16): 4545-4548, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146099

RESUMO

In the field of coherent diffraction imaging, phase retrieval is essential for correcting the aberration of an optic system. For estimating aberration from intensity, conventional methods rely on neural networks whose performance is limited by training datasets. In this Letter, we propose an untrained physics-driven aberration retrieval network (uPD-ARNet). It only uses one intensity image and iterates in a self-supervised way. This model consists of two parts: an untrained neural network and a forward physical model for the diffraction of the light field. This physical model can adjust the output of the untrained neural network, which can characterize the inverse process from the intensity to the aberration. The experiments support that our method is superior to other conventional methods for aberration retrieval.

18.
Opt Lett ; 49(3): 474-477, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300037

RESUMO

With the rapid development of information era, the traditional von Neumann architecture faces the computing bottleneck, and integration of memory and perception is regarded as a potential solution. Herein, a Ga2O3/Si heterojunction based multi-modulated optoelectronic synaptic device is fabricated and demonstrated. As stimulated by ultraviolet (UV) optical spikes, the heterojunction device reveals typical synaptic functions of excitatory-postsynaptic current (EPSC), paired-pulse facilitation (PPF), spike-timing-dependent plasticity (STDP), and switch between short-term memory (STM) and long-term memory (LTM). In addition, stronger stimulations like higher reading voltage, stronger optical stimulated intensity, and longer pulse duration time can significantly prolong the attenuation of EPSC, which contributes to the improvement of the forgetting process. Our work provides a potential strategy for future neuromorphic computation through a UV light driven stimulation.

19.
Cancer Cell Int ; 24(1): 84, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402182

RESUMO

BACKGROUND: The incidence of multiple primary cancers (MPC), especially involving primary lung cancer (PLC) and primary hematologic malignancies (PHM), is rising. This study aims to analyze clinicopathological features, gene abnormalities, and prognostic outcomes in individuals diagnosed with PLC-PHM MPC. METHODS: A retrospective analysis included 89 patients diagnosed with PLC-PHM MPC at the Respiratory or Hematology Departments of Ruijin Hospital from 2003 to 2022 (a total of 842,047 people). Next-generation sequencing (NGS) assessed lung cancer specimens, while Polymerase Chain Reaction (PCR) and NGS were used for hematologic malignancy specimens. Statistical analysis involved survival analysis and Cox regression. RESULTS: PLC-PHM MPC incidence surged from 1.67 per year (2011-2013) to 16.3 per year (2020-2022). The primary demographic for PLC-PHM MPC consists predominantly of elderly (average age 66 years) males (59.6%), with a high prevalence of metachronous MPC (89.9%). The prevailing histological types were lung adenocarcinoma (70.8%) in lung cancer (LC) and mature B-cell lymphomas (50.6%) in hematologic malignancies (HM). Notably, in a molecular testing cohort of 38 LC patients, 84.2% of lung cancer cases exhibited driver mutations, in which EGFR mutations frequence prevalent was 74.2%. In total group of 85 cases achieved a median overall survival (mOS) of 46.2 months, with a 5-year survival rate of 37.9% and advanced LC patients with LC gene mutations achieved a mOS was 52.6 months, with a 5-year OS rate of 30.6%. The median progression-free survival (PFS) following first-line treatment of 11 advanced patients with lung cancer-associated driver gene mutations is 26.6 months. Multivariate Cox regression revealed a favorable OS associated with surgery for LC, favorable PS score, adenocarcinoma pathology of LC, and the presence of genetic abnormalities associated with HM. CONCLUSION: PLC-PHM MPC incidence is rising, characterized by a significant proportion of lung adenocarcinoma and a high prevalence of positive driver genes, especially in EGFR. Despite suffering from two primary tumors, the PLC-PHM MPC patients had superior data of both PFS and OS, suggesting an inherently intricate background of genetic abnormalities between the two kinds of tumors.

20.
Phys Rev Lett ; 133(2): 024001, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39073953

RESUMO

Over the past century, drops production mechanisms from bubble bursting have been extensively studied. They include the centrifugal fragmentation of liquid ligaments from the bubble cap during film rupture, the flapping of the cap film, and the disintegration of Worthington jets after cavity collapse. We show here that a dominant fraction of previously identified as "surface bubble bursting" submicron drops are, in fact, generated underwater, in the abyss, inside the bubbles themselves before they have reached the surface. Several experimental evidences demonstrate that these drops originate from the flapping instability of the film squeezed between underwater colliding bubbles. This finding, emphasizing the eminent role of bubble-bubble collisions, alters fundamentally our understanding of fine aerosol production and opens a novel perspective for transfers across water-air interfaces.

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