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1.
Cancer ; 130(S8): 1524-1538, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38515388

RESUMO

BACKGROUND: Studies on various thrombopoietic agents for cancer treatment-induced thrombocytopenia (CTIT) in China are lacking. This study aimed to provide detailed clinical profiles to understand the outcomes and safety of different CTIT treatment regimens. METHODS: In this retrospective, cross-sectional study, 1664 questionnaires were collected from 33 hospitals between March 1 and July 1, 2021. Patients aged >18 years were enrolled who were diagnosed with CTIT and treated with recombinant interleukin 11 (rhIL-11), recombinant thrombopoietin (rhTPO), or a thrombopoietin receptor agonist (TPO-RA). The outcomes, compliance, and safety of different treatments were analyzed. RESULTS: Among the 1437 analyzable cases, most patients were treated with either rhTPO alone (49.3%) or rhIL-11 alone (27.0%). The most common combination regimen used was rhTPO and rhIL-11 (10.9%). Platelet transfusions were received by 117 cases (8.1%). In multivariate analysis, rhTPO was associated with a significantly lower proportion of platelet recovery, platelet transfusion, and hospitalization due to chemotherapy-induced thrombocytopenia (CIT) than rhIL-11 alone. No significant difference was observed in the time taken to achieve a platelet count of >100 × 109/L and chemotherapy dose reduction due to CIT among the different thrombopoietic agents. The outcomes of thrombocytopenia in 170 patients who received targeted therapy and/or immunotherapy are also summarized. The results show that the proportion of platelet recovery was similar among the different thrombopoietic agents. No new safety signals related to thrombopoietic agents were observed in this study. A higher proportion of physicians preferred to continue treatment with TPO-RA alone than with rhTPO and rhIL-11. CONCLUSIONS: This survey provides an overview of CTIT and the application of various thrombopoietic agents throughout China. Comparison of monotherapy with rhIL-11, rhTPO, and TPO-RA requires further randomized clinical trials. The appropriate application for thrombopoietic agents should depend on the pretreatment of platelets, treatment variables, and risk of bleeding. PLAIN LANGUAGE SUMMARY: To provide an overview of the outcome of cancer treatment-induced thrombocytopenia in China, our cross-sectional study analyzed 1437 cases treated with different thrombopoietic agents. Most of the patients were treated with recombinant interleukin 11 (rhIL-11) and recombinant thrombopoietin (rhTPO). rhTPO was associated with a significantly lower proportion of platelet recovery and platelet transfusion compared with rhIL-11.


Assuntos
Neoplasias , Trombocitopenia , Humanos , China , Estudos Transversais , Interleucina-11/uso terapêutico , Neoplasias/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Trombopoetina/uso terapêutico , Adulto Jovem , Adulto
2.
Front Immunol ; 15: 1267963, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464509

RESUMO

Background: Coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM) are closely related. The function of immunocytes in the pathogenesis of CAD and T2DM has not been extensively studied. The quantitative bioinformatics analysis of the public RNA sequencing database was applied to study the key genes that mediate both CAD and T2DM. The biological characteristics of associated key genes and mechanism of CD8+ T and NK cells in CAD and T2DM are our research focus. Methods: With expression profiles of GSE66360 and GSE78721 from the Gene Expression Omnibus (GEO) database, we identified core modules associated with gene co-expression relationships and up-regulated genes in CAD and T2DM using Weighted Gene Co-expression Network Analysis (WGCNA) and the 'limma' software package. The enriched pathways of the candidate hub genes were then explored using GO, KEGG and GSEA in conjunction with the immune gene set (from the MSigDB database). A diagnostic model was constructed using logistic regression analysis composed of candidate hub genes in CAD and T2DM. Univariate Cox regression analysis revealed hazard ratios (HRs), 95% confidence intervals (CIs), and p-values for candidate hub genes in diagnostic model, while CIBERSORT and immune infiltration were used to assess the immune microenvironment. Finally, monocytes from peripheral blood samples and their immune cell ratios were analyzed by flow cytometry to validate our findings. Results: Sixteen candidate hub genes were identified as being correlated with immune infiltration. Univariate Cox regression analysis revealed that NPEPPS and ABHD17A were highly correlated with the diagnosis of CAD and T2DM. The results indicate that CD8+ T cells (p = 0.04) and NKbright cells (p = 3.7e-3) are significantly higher in healthy controls than in individuals with CAD or CAD combined with T2DM. The bioinformatics results on immune infiltration were well validated by flow cytometry. Conclusions: A series of bioinformatics studies have shown ABHD17A and NPEPPS as key genes for the co-occurrence of CAD and T2DM. Our study highlights the important effect of CD8+ T and NK cells in the pathogenesis of both diseases, indicating that they may serve as viable targets for diagnosis and therapeutic intervention.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Humanos , Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 2/genética , Regulação para Cima , Linfócitos T CD8-Positivos , Células Matadoras Naturais , Bases de Dados de Ácidos Nucleicos
3.
Nat Commun ; 14(1): 8519, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129386

RESUMO

The cyclic GMP-AMP synthase (cGAS)/stimulator of interferon gene (STING) signaling pathway plays a critical protective role against viral infections. Metazoan STING undergoes multilayers of regulation to ensure specific signal transduction. However, the mechanisms underlying the regulation of bacterial STING remain unclear. In this study, we determined the crystal structure of anti-parallel dimeric form of bacterial STING, which keeps itself in an inactive state by preventing cyclic dinucleotides access. Conformational transition between inactive and active states of bacterial STINGs provides an on-off switch for downstream signaling. Some bacterial STINGs living in extreme environment contain an insertion sequence, which we show codes for an additional long lid that covers the ligand-binding pocket. This lid helps regulate anti-phage activities. Furthermore, bacterial STING can bind cyclic di-AMP in a triangle-shaped conformation via a more compact ligand-binding pocket, forming spiral-shaped protofibrils and higher-order fibril filaments. Based on the differences between cyclic-dinucleotide recognition, oligomerization, and downstream activation of different bacterial STINGs, we proposed a model to explain structure-function evolution of bacterial STINGs.


Assuntos
Bactérias , Transdução de Sinais , Animais , Ligantes , Bactérias/metabolismo , Genes Bacterianos , Nucleotidiltransferases/metabolismo , Imunidade Inata
4.
Cardiovasc J Afr ; 34: 1-5, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37906467

RESUMO

AIM: The aim of the study was to analyse the correlation between maternally expressed gene 3 (MEG3) expression and heart rate variability (HRV) in heart failure patients with ventricular arrhythmia (VA). METHODS: A total of 130 heart failure patients, treated from July 2018 to March 2021, were prospectively selected and divided into a non-VA group (n = 85) and a VA group (n = 45) according to the presence or absence of VA. The correlations of serum MEG3 expression and HRV with cardiac function indicators were investigated by Pearson correlation analysis. Receiver operating characteristic (ROC) curves were plotted to assess the predictive value of MEG3, HRV and their combination for the occurrence of heart failure complicated with VA. RESULTS: The VA group had a higher left atrial diameter (LAD) and left ventricular end-diastolic diameter (LVEDD) but lower left ventricular ejection fraction (LVEF) and ratio of mitral early diastolic peak velocity (E) to late peak atrial filling velocity (A) (E/A) than the non-VA group (p < 0.05). The serum MEG3 expression was negatively correlated with: standard deviation of the average RR intervals calculated over five-minute segments in the 24-hour record (SDANN), SDANN index, standard deviation of normal-to-normal RR interval (SDNN) index, percentage of differences between adjacent normal RR intervals exceeding 50 ms (PNN50), root mean square of successive difference (RMSSD), low frequency (LF), high frequency (HF), very low frequency (VLF), LVEF and E/A (r < 0, p < 0.05). The serum MEG3 expression was positively correlated with LAD and LVEDD (r > 0, p < 0.05). The areas under the ROC curves of MEG3, SDANN, SDANN index, SDNN index, PNN50, RMSSD, LF, HF, VLF and their combination for the prediction of the occurrence of heart failure complicated with VA were 0.812, 0.731, 0.737, 0.689, 0.860, 0.783, 0.791, 0.856, 0.769 and 0.966, respectively. CONCLUSION: MEG3 combined with HRV can effectively predict the occurrence of heart failure complicated with VA.

5.
World J Clin Cases ; 11(24): 5692-5699, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37727708

RESUMO

BACKGROUND: Biliary adenomas that occur in the extrahepatic biliary tree are rare. It is difficult to distinguish it from cholangiocarcinoma or cholangiolithiasis by various imaging examinations, and it is very easy to be misdiagnosed. AIM: To evaluate the cumulative experiences including clinical characteristics and treatments of nine patients diagnosed with extrahepatic biliary adenoma admitted to the First Affiliated Hospital of Xi'an Jiaotong University from 2016 to 2022. METHODS: A total of nine patients were included in our study. The laboratory examinations, disease diagnosis, therapy and pathological characteristics, and follow-up of every patient were evaluated. RESULTS: Our cohort consisted of six females and three males with an average diagnosis age of 65.1 years (range 46-87). Six extrahepatic biliary adenomas were located in the common bile ducts and three in the hepatic duct. On initial presentation, all of the patients have symptom of biliary origin, including obstructive jaundice (4/9, 44.4%), abdominal pain (6/9, 66.7%), and fever (3/9, 33.3%). Preoperative imaging examination considered bile duct carcinoma in 6 cases and bile duct calculi in 3 cases. All the patients received surgical treatment and were confirmed by pathology as biliary adenoma. The symptoms improved significantly in all 9 patients after surgery. Seven of nine patients recovered well at follow-up without tumor recurrence. One patient died 2 mo after the surgery due to heart failure. One patient developed jaundice again 8 mo after surgery, underwent endoscopic retrograde cholangiopancreatography and biliary stent placement. CONCLUSION: Benign extrahepatic biliary tumors are rare and difficult to diagnosis preoperatively. Intraoperative choledochoscopy and timely biopsy may offer great advantages.

6.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707487

RESUMO

In viral evolution, a new mutation has to proliferate within the host (Stage I) in order to be transmitted and then compete in the host population (Stage II). We now analyze the intrahost single nucleotide variants (iSNVs) in a set of 79 SARS-CoV-2 infected patients with most transmissions tracked. Here, every mutation has two measures: 1) iSNV frequency within each individual host in Stage I; 2) occurrence among individuals ranging from 1 (private), 2-78 (public), to 79 (global) occurrences in Stage II. In Stage I, a small fraction of nonsynonymous iSNVs are sufficiently advantageous to rise to a high frequency, often 100%. However, such iSNVs usually fail to become public mutations. Thus, the selective forces in the two stages of evolution are uncorrelated and, possibly, antagonistic. For that reason, successful mutants, including many variants of concern, have to avoid being eliminated in Stage I when they first emerge. As a result, they may not have the transmission advantage to outcompete the dominant strains and, hence, are rare in the host population. Few of them could manage to slowly accumulate advantageous mutations to compete in Stage II. When they do, they would appear suddenly as in each of the six successive waves of SARS-CoV-2 strains. In conclusion, Stage I evolution, the gate-keeper, may contravene the long-term viral evolution and should be heeded in viral studies.


Assuntos
COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2/genética , Mutação
7.
Nat Commun ; 14(1): 5078, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37604815

RESUMO

Purine-containing nucleotide second messengers regulate diverse cellular activities. Cyclic di-pyrimidines mediate anti-phage functions in bacteria; however, the synthesis mechanism remains elusive. Here, we determine the high-resolution structures of cyclic di-pyrimidine-synthesizing cGAS/DncV-like nucleotidyltransferases (CD-NTases) in clade E (CdnE) in its apo, substrate-, and intermediate-bound states. A conserved (R/Q)xW motif controlling the pyrimidine specificity of donor nucleotide is identified. Mutation of Trp or Arg from the (R/Q)xW motif to Ala rewires its specificity to purine nucleotides, producing mixed purine-pyrimidine cyclic dinucleotides (CDNs). Preferential binding of uracil over cytosine bases explains the product specificity of cyclic di-pyrimidine-synthesizing CdnE to cyclic di-UMP (cUU). Based on the intermediate-bound structures, a synthetic pathway for cUU containing a unique 2'3'-phosphodiester linkage through intermediate pppU[3'-5']pU is deduced. Our results provide a framework for pyrimidine selection and establish the importance of conserved residues at the C-terminal loop for the specificity determination of CD-NTases.


Assuntos
Nucleotidiltransferases , Pirimidinas , Nucleotidiltransferases/genética , Nucleotídeos , Cromogranina A , Nucleotídeos de Purina
8.
New Phytol ; 239(4): 1505-1520, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37306069

RESUMO

Flowering time is a key agronomic trait determining environmental adaptation and yield potential of crops. The regulatory mechanisms of flowering in maize still remain rudimentary. In this study, we combine expressional, genetic, and molecular studies to identify two homologous SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors ZmSPL13 and ZmSPL29 as positive regulators of juvenile-to-adult vegetative transition and floral transition in maize. We show that both ZmSPL13 and ZmSPL29 are preferentially expressed in leaf phloem, vegetative and reproductive meristem. We show that vegetative phase change and flowering time are moderately delayed in the Zmspl13 and Zmspl29 single knockout mutants and more significantly delayed in the Zmspl13/29 double mutants. Consistently, the ZmSPL29 overexpression plants display precocious vegetative phase transition and floral transition, thus early flowering. We demonstrate that ZmSPL13 and ZmSPL29 directly upregulate the expression of ZmMIR172C and ZCN8 in the leaf, and of ZMM3 and ZMM4 in the shoot apical meristem, to induce juvenile-to-adult vegetative transition and floral transition. These findings establish a consecutive signaling cascade of the maize aging pathway by linking the miR156-SPL and the miR172-Gl15 regulatory modules and provide new targets for genetic improvement of flowering time in maize cultivars.


Assuntos
Flores , Proteínas de Plantas , Proteínas de Plantas/metabolismo , Flores/fisiologia , Zea mays/genética , Zea mays/metabolismo , Folhas de Planta/metabolismo , Meristema/genética , Meristema/metabolismo , Regulação da Expressão Gênica de Plantas
9.
Talanta ; 265: 124815, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348355

RESUMO

Cancer is one of the major diseases that seriously endanger the health of all mankind. Accurate diagnosis of early cancer is the most promising way to reduce cancer harm and improve patient survival. However, many developed fluorescent probes for cancer imaging only have the function of identifying one marker, which cannot meet the needs of accurate diagnosis. Here, a fluorescent nanoprobe (CPH@ZIF-90) utilizing ZIF-90 to encapsulate SO2-sensitive dye (CPH) is synthesized for the sequential detection of ATP and SO2. The nanoprobe first interacts with ATP to release CPH, thus increasing the fluorescence at 685 nm and realizing the near-infrared (NIR) fluorescence detection of ATP. Then, SO2 acts on the released CPH through nucleophilic addition, affecting the π-conjugated structure of CPH and resulting in enhanced fluorescence at 580 nm. CPH@ZIF-90 exhibits satisfactory sensitivity and selectivity for sequential detection of ATP and SO2. Excitedly, CPH@ZIF-90 can sequentially image the endogenous ATP and SO2 in cells, showing sensitive fluorescence changes in dual channels (red and green). Due to the NIR emission properties of CPH@ZIF-90 and its ability to enrich in tumor, it is applied to monitor ATP and SO2 in mice and distinguish normal mice from tumor mice. The ability of CPH@ZIF-90 to sequentially detect two cancer-related biomarkers makes it provide meaningful assistance in accurate early diagnosis of cancer.


Assuntos
Neoplasias , Dióxido de Enxofre , Animais , Camundongos , Trifosfato de Adenosina , Corantes Fluorescentes/química , Diagnóstico por Imagem , Neoplasias/diagnóstico por imagem
10.
Sci Rep ; 13(1): 7600, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165042

RESUMO

Semantic segmentation of remote sensing imagery (RSI) is critical in many domains due to the diverse landscapes and different sizes of geo-objects that RSI contains, making semantic segmentation challenging. In this paper, a convolutional network, named Adaptive Feature Fusion UNet (AFF-UNet), is proposed to optimize the semantic segmentation performance. The model has three key aspects: (1) dense skip connections architecture and an adaptive feature fusion module that adaptively weighs different levels of feature maps to achieve adaptive feature fusion, (2) a channel attention convolution block that obtains the relationship between different channels using a tailored configuration, and (3) a spatial attention module that obtains the relationship between different positions. AFF-UNet was evaluated on two public RSI datasets and was quantitatively and qualitatively compared with other models. Results from the Potsdam dataset showed that the proposed model achieved an increase of 1.09% over DeepLabv3 + in terms of the average F1 score and a 0.99% improvement in overall accuracy. The visual qualitative results also demonstrated a reduction in confusion of object classes, better performance in segmenting different sizes of object classes, and better object integrity. Therefore, the proposed AFF-UNet model optimizes the accuracy of RSI semantic segmentation.

11.
Plant J ; 115(3): 772-787, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37186341

RESUMO

Maize (Zea mays L.) is a major staple crop worldwide, and during modern maize breeding, cultivars with increased tolerance to high-density planting and higher yield per plant have contributed significantly to the increased yield per unit land area. Systematically identifying key agronomic traits and their associated genomic changes during modern maize breeding remains a significant challenge because of the complexity of genetic regulation and the interactions of the various agronomic traits, with most of them being controlled by numerous small-effect quantitative trait loci (QTLs). Here, we performed phenotypic and gene expression analyses for a set of 137 elite inbred lines of maize from different breeding eras in China. We found four yield-related traits are significantly improved during modern maize breeding. Through gene-clustering analyses, we identified four groups of expressed genes with distinct trends of expression pattern change across the historical breeding eras. In combination with weighted gene co-expression network analysis, we identified several candidate genes regulating various plant architecture- and yield-related agronomic traits, such as ZmARF16, ZmARF34, ZmTCP40, ZmPIN7, ZmPYL10, ZmJMJ10, ZmARF1, ZmSWEET15b, ZmGLN6 and Zm00001d019150. Further, by combining expression quantitative trait loci (eQTLs) analyses, correlation coefficient analyses and population genetics, we identified a set of candidate genes that might have been under selection and contributed to the genetic improvement of various agronomic traits during modern maize breeding, including a number of known key regulators of plant architecture, flowering time and yield-related traits, such as ZmPIF3.3, ZAG1, ZFL2 and ZmBES1. Lastly, we validated the functional variations in GL15, ZmPHYB2 and ZmPYL10 that influence kernel row number, flowering time, plant height and ear height, respectively. Our results demonstrates the effectiveness of our combined approaches for uncovering key candidate regulatory genes and functional variation underlying the improvement of important agronomic traits during modern maize breeding, and provide a valuable genetic resource for the molecular breeding of maize cultivars with tolerance for high-density planting.


Assuntos
Melhoramento Vegetal , Locos de Características Quantitativas , Zea mays , Perfilação da Expressão Gênica , Locos de Características Quantitativas/genética , Variação Genética , Zea mays/genética , Zea mays/metabolismo
13.
Parasitology ; 150(8): 661-671, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37051880

RESUMO

Trematodes of the genus Ogmocotyle are intestinal flukes that can infect a variety of definitive hosts, resulting in significant economic losses worldwide. However, there are few studies on molecular data of these trematodes. In this study, the mitochondrial (mt) genome of Ogmocotyle ailuri isolated from red panda (Ailurus fulgens) was determined and compared with those from Pronocephalata to investigate the mt genome content, genetic distance, gene rearrangements and phylogeny. The complete mt genome of O. ailuri is a typical closed circular molecule of 14 642 base pairs, comprising 12 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions. All genes are transcribed in the same direction. In addition, 23 intergenic spacers and 2 locations with gene overlaps were determined. Sequence identities and sliding window analysis indicated that cox1 is the most conserved gene among 12 PCGs in O. ailuri mt genome. The sequenced mt genomes of the 48 Plagiorchiida trematodes showed 5 types of gene arrangement based on all mt genome genes, with the gene arrangement of O. ailuri being type I. Phylogenetic analysis using concatenated amino acid sequences of 12 PCGs revealed that O. ailuri was closer to Ogmocotyle sikae than to Notocotylus intestinalis. These data enhance the Ogmocotyle mt genome database and provide molecular resources for further studies of Pronocephalata taxonomy, population genetics and systematics.


Assuntos
Ailuridae , Genoma Mitocondrial , Trematódeos , Infecções por Trematódeos , Filogenia , Trematódeos/classificação , Trematódeos/genética , Infecções por Trematódeos/veterinária , Animais
14.
Acupunct Med ; 41(3): 130-141, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36760118

RESUMO

BACKGROUND: Trigger point (TrP) acupuncture is commonly used to treat chronic non-specific low back pain (CNLBP). Evidence for the efficacy of most TrP acupuncture modalities is weak or lacking. OBJECTIVE: To assess the effect of TrP acupuncture on pain, disability, gait and muscle activation in patients with CNLBP. METHODS: From May 2019 to February 2020, a randomised, single-blind clinical trial was carried out involving 33 participants with CNLBP, divided into one of two intervention groups or a control group (n = 11 per group). The intervention groups received TrP acupuncture or traditional acupuncture treatment three times a week for 4 weeks, and the control group remained on a waiting list and received no treatment. Pain, disability, gait and muscle activation were assessed at baseline and at 4 and 8 weeks of follow-up. RESULTS: At baseline, the three groups showed no significant differences in age, gender, height, weight, body mass index (BMI) or disease course (p ⩾ 0.05). At 4 weeks, pain was relieved (measured by visual analogue scores, p = 0.036) and disability was improved (reflected by lower Oswestry disability index scores, p = 0.029) in TrP acupuncture versus waiting list groups. Moreover, lumbar extension range of motion was increased in TrP acupuncture versus both traditional acupuncture and waiting list groups (p = 0.029 and p = 0.027, respectively). At 8 weeks, there were no significant differences in any parameter between the three groups (p > 0.05). CONCLUSION: TrP acupuncture had a significant short-term effect on pain relief and disability in patients with CNLBP, but there was no evidence of a long-term influence (at 8 weeks following the intervention). Further high-quality randomised controlled trials are needed for verification in the future.Trial registration number: ChiCTR1900022838 (Chinese Clinical Trial Registry).


Assuntos
Terapia por Acupuntura , Dor Crônica , Dor Lombar , Humanos , Dor Crônica/terapia , Dor Lombar/terapia , Medição da Dor , Método Simples-Cego , Resultado do Tratamento , Pontos-Gatilho
15.
Int J Biol Macromol ; 237: 123656, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796558

RESUMO

Under selective pressure, bacteria have evolved diverse defense systems against phage infections. The SMODS-associated and fused to various effector domains (SAVED)-domain containing proteins were identified as major downstream effectors in cyclic oligonucleotide-based antiphage signaling system (CBASS) for bacterial defense. Recent study structurally characterizes a cGAS/DncV-like nucleotidyltransferase (CD-NTase)-associated protein 4 from Acinetobacter baumannii (AbCap4) in complex with 2'3'3'-cyclic AMP-AMP-AMP (cAAA). However, the homologue Cap4 from Enterobacter cloacae (EcCap4) is activated by 3'3'3'-cyclic AMP-AMP-GMP (cAAG). To elucidate the ligand specificity of Cap4 proteins, we determined the crystal structures of full-length wild-type and K74A mutant of EcCap4 to 2.18 and 2.42 Å resolution, respectively. The DNA endonuclease domain of EcCap4 shares similar catalytic mechanism with type II restriction endonuclease. Mutating the key residue K74 in the conserved DXn(D/E)XK motif completely abolishes its DNA degradation activity. The potential ligand-binding cavity of EcCap4 SAVED domain is located adjacent to its N-terminal domain, significantly differing from the centrally located cavity of AbCap4 SAVED domain which recognizes cAAA. Based on structural and bioinformatic analysis, we found that Cap4 proteins can be classified into two types: the type I Cap4, like AbCap4, recognize cAAA and the type II Cap4, like EcCap4, bind cAAG. Several conserved residues identified at the surface of potential ligand-binding pocket of EcCap4 SAVED domain are confirmed by ITC experiment for their direct binding roles for cAAG. Changing Q351, T391 and R392 to alanine abolished the binding of cAAG by EcCap4 and significantly reduced the anti-phage ability of the E. cloacae CBASS system constituting EcCdnD (CD-NTase in clade D) and EcCap4. In summary, we revealed the molecular basis for specific cAAG recognition by the C-terminal SAVED domain of EcCap4 and demonstrates the structural differences for ligand discrimination among different SAVED-domain containing proteins.


Assuntos
Bacteriófagos , Bacteriófagos/metabolismo , Proteínas de Bactérias/química , Oligonucleotídeos , Ligantes , GMP Cíclico/metabolismo , Bactérias/metabolismo , AMP Cíclico
17.
Nat Genet ; 55(2): 312-323, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646891

RESUMO

Hybrid maize displays superior heterosis and contributes over 30% of total worldwide cereal production. However, the molecular mechanisms of heterosis remain obscure. Here we show that structural variants (SVs) between the parental lines have a predominant role underpinning maize heterosis. De novo assembly and analyses of 12 maize founder inbred lines (FILs) reveal abundant genetic variations among these FILs and, through expression quantitative trait loci and association analyses, we identify several SVs contributing to genomic and phenotypic differentiations of various heterotic groups. Using a set of 91 diallel-cross F1 hybrids, we found strong positive correlations between better-parent heterosis of the F1 hybrids and the numbers of SVs between the parental lines, providing concrete genomic support for a prevalent role of genetic complementation underlying heterosis. Further, we document evidence that SVs in both ZAR1 and ZmACO2 contribute to yield heterosis in an overdominance fashion. Our results should promote genomics-based breeding of hybrid maize.


Assuntos
Vigor Híbrido , Zea mays , Grão Comestível/genética , Vigor Híbrido/genética , Hibridização Genética , Melhoramento Vegetal , Locos de Características Quantitativas/genética , Zea mays/genética , Genoma de Planta
18.
Plant Cell ; 35(1): 369-389, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36173348

RESUMO

Maize (Zea mays) originated in southern Mexico and has spread over a wide latitudinal range. Maize expansion from tropical to temperate regions has necessitated a reduction of its photoperiod sensitivity. In this study, we cloned a quantitative trait locus (QTL) regulating flowering time in maize and show that the maize ortholog of Arabidopsis thaliana EARLY FLOWERING3, ZmELF3.1, is the causal locus. We demonstrate that ZmELF3.1 and ZmELF3.2 proteins can physically interact with ZmELF4.1/4.2 and ZmLUX1/2, to form evening complex(es; ECs) in the maize circadian clock. Loss-of-function mutants for ZmELF3.1/3.2 and ZmLUX1/2 exhibited delayed flowering under long-day and short-day conditions. We show that EC directly represses the expression of several flowering suppressor genes, such as the CONSTANS, CONSTANS-LIKE, TOC1 (CCT) genes ZmCCT9 and ZmCCT10, ZmCONSTANS-LIKE 3, and the PSEUDORESPONSE REGULATOR (PRR) genes ZmPRR37a and ZmPRR73, thus alleviating their inhibition, allowing florigen gene expression and promoting flowering. Further, we identify two closely linked retrotransposons located in the ZmELF3.1 promoter that regulate the expression levels of ZmELF3.1 and may have been positively selected during postdomestication spread of maize from tropical to temperate regions during the pre-Columbian era. These findings provide insights into circadian clock-mediated regulation of photoperiodic flowering in maize and new targets of genetic improvement for breeding.


Assuntos
Arabidopsis , Zea mays , Zea mays/metabolismo , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptação Fisiológica/genética , Aclimatação/genética , Fotoperíodo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética
19.
Zhongguo Fei Ai Za Zhi ; 25(11): 771-781, 2022 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-36419390

RESUMO

BACKGROUND: Acquired and primary resistance to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) is still the bottleneck of clinical treatment of advanced non-small cell lung cancer (NSCLC). STE029 is a novel anticancer drug which consists of 3-hydroxy-3-methylglutarylcoenzyme A reductase (HMGCR) inhibitor and novel cancer cell membrane targeting molecular. This study aimed to investigate the reversal mechanism of EGFR-TKI resistance by STE029 in lung adenocarcinoma. METHODS: CCK8 test was used to test the cell viability and survival rate of EGFR mutated PC9 cell (Gefitinib sensitive), PC9/BB4 cell (acquired Gefitinib resistant), and EGFR wild type A549 cell after treatment of STE029, Gefitinib or combination of both. EdU test was applied to detect changes in cell cycle and Hoechst 33258 was applied to detect apoptosis rate in overcoming the EGFR-TKI resistance. The activity of EGFR/PI3K/Akt, cell cycle and apoptosis signal pathways were examined. In vivo, nude mice were exposed to STE029, Gefitinib and STE029+Gefitinib for 5 wk. And the the tumor volume was measured and tumor weight was obtained on the last day. RESULTS: (1) PC9 cells was highly sensitive to Gefitinib, while PC9/BB4 and A549 cell showed significant resistance to Gefitinib treatment; (2) STE029+Gefitinib treatment could significantly decrease the 50% inhibitory concentrarion (IC50) of Gefitinib in PC9, PC9/BB4 and A549 cells (P<0.05, respectively); (3) In PC9 and PC9/BB4 cells, STE029+Gefitinib can block cell cycle and inhibit cell proliferation (P<0.001), while there was no significant difference in apoptosis rate among three drug intervention groups (P>0.05); However, apoptosis rate was increased in STE029+Gefitinib group in A549 cell (P<0.01), while no significance detected in cell proliferation (P>0.05). (4) In PC9 and PC9/BB4 cells, the combination of STE029 and Gefitinib could downregulate p-EGFR, p-Akt, p-Cyclin D1 and Cyclin D1 (P<0.001), and upregulate the expression of GSK-3ß (P<0.001), and the expression of cleaved caspase-8, caspase-8 cleaved caspase-9, caspase-9 showed no difference among groups (P>0.05). In A549 cells, the combination of STE029 and Gefitinib could downregulate p-Akt (P<0.001) and upregulate cleaved caspase-8 and cleaved caspase-9 (P<0.001); (5)In vivo, the combination of STE029 and Gefitinib effectively inhibited tumor development and progression compared to STE029 alone or Gefitinib alone, with significant difference (P<0.05) in PC9 and PC9/BB4 xenografted tumor. CONCLUSIONS: STE029 could sensitize Gefitinib by inhibiting EGFR/PI3K/Akt pathway, blocking the tumor cell cycle and proliferation and inducing apoptosis through caspase-8 and caspase-9 dependent pathway. STE029 deserves further investigations in overcoming EGFR-TKI resistance in lung cancer.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Camundongos , Humanos , Gefitinibe/farmacologia , Caspase 9 , Caspase 8 , Ciclina D1 , Glicogênio Sintase Quinase 3 beta , Camundongos Nus , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Receptores ErbB/genética
20.
Heliyon ; 8(11): e11503, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36411886

RESUMO

Metformin is a drug that has been applied in clinical use for many years for the treatment of type 2 diabetes mellitus (T2DM). It achieves its function through multiple targets and modulation of multiple signaling pathways. To date, the mechanism of the action of metformin is still not fully understood. Along with glycemic control, metformin has shown good inhibitory effects on the development of many tumors. Here, we elucidated that plasma exosomal microRNA-122-5p (miR-122) is closely related to the mechanism of metformin. MiR-122 regulates glycogen-glucose metabolism in hepatocytes or hepatocellular carcinoma cells (HCC) by inhibiting the phosphorylation of AMPK. Since miR-122 and metformin regulate glucose metabolism homeostasis through similar mechanisms, miR-122 can antagonize the effects of metformin. MiR-122 expression increases the sensitivity of hepatocytes or HCC to metformin. Conversely, decreased expression of miR-122 results in hepatocyte insensitivity to metformin. Therefore, significantly elevated levels of miR-122 in plasma exosomes of hepatocellular carcinoma patients could enhance their sensitivity to metformin. The results of the present study revealed a key regulatory role of plasma exosomal miR-122 on the molecular mechanism of metformin. The regulation of key molecules of related signaling pathways by miR-122 may lead to similar glycemic lowering and tumor suppression therapeutic effects as metformin. This provides new ideas for the development of new therapeutic strategies for hepatocellular carcinoma based on the mechanism of miR-122 and metformin.

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