RESUMO
The properties of polycrystalline materials are often dominated by defects; two-dimensional (2D) crystals can even be divided and disrupted by a line defect1-3. However, 2D crystals are often required to be processed into films, which are inevitably polycrystalline and contain numerous grain boundaries, and therefore are brittle and fragile, hindering application in flexible electronics, optoelectronics and separation1-4. Moreover, similar to glass, wood and plastics, they suffer from trade-off effects between mechanical strength and toughness5,6. Here we report a method to produce highly strong, tough and elastic films of an emerging class of 2D crystals: 2D covalent organic frameworks (COFs) composed of single-crystal domains connected by an interwoven grain boundary on water surface using an aliphatic bi-amine as a sacrificial go-between. Films of two 2D COFs have been demonstrated, which show Young's moduli and breaking strengths of 56.7 ± 7.4 GPa and 73.4 ± 11.6 GPa, and 82.2 ± 9.1 N m-1 and 29.5 ± 7.2 N m-1, respectively. We predict that the sacrificial go-between guided synthesis method and the interwoven grain boundary will inspire grain boundary engineering of various polycrystalline materials, endowing them with new properties, enhancing their current applications and paving the way for new applications.
RESUMO
Chemical modifications in RNAs play crucial roles in diversifying their structures and regulating numerous biochemical processes. Since the 1990s, several hydrophobic prenyl-modifications have been discovered in various RNAs. Prenyl groups serve as precursors for terpenes and many other biological molecules. The processes of prenylation in different macromolecules have been extensively studied. We introduce here a novel chemical biology toolkit that not only labels i6A, a prenyl-modified RNA residue, by leveraging the unique reactivity of the prenyl group, but also provides a general strategy to incorporate fluorescence functionalities into RNAs for molecular tracking purposes. Our findings revealed that iodine-mediated cyclization reactions of the prenyl group occur rapidly, transforming i6A from a hydrogen-bond acceptor to a donor. Based on this reactivity, we developed an Iodine-Mediated Cyclization and Reverse Transcription (IMCRT) tRNA-seq method, which can profile all nine endogenous tRNAs containing i6A residues in Saccharomyces cerevisiae with single-base resolution. Furthermore, under stress conditions, we observed a decline in i6A levels in budding yeast, accompanied by significant decrease of mutation rate at A37 position. Thus, the IMCRT tRNA-seq method not only permits semi-quantification of i6A levels in tRNAs but also holds potential for transcriptome-wide detection and analysis of various RNA species containing i6A modifications.
Assuntos
Isopenteniladenosina , Processamento Pós-Transcricional do RNA , RNA de Transferência , Iodo , Neopreno , RNA de Transferência/metabolismo , Saccharomyces cerevisiae , Análise de Sequência de RNARESUMO
BACKGROUND: The benefit:risk profile of bivalirudin versus heparin anticoagulation in patients with non-ST-segment-elevation myocardial infarction undergoing percutaneous coronary intervention (PCI) is uncertain. Study-level meta-analyses lack granularity to provide conclusive answers. We sought to compare the outcomes of bivalirudin and heparin in patients with non-ST-segment-elevation myocardial infarction undergoing PCI. METHODS: We performed an individual patient data meta-analysis of patients with non-ST-segment-elevation myocardial infarction in all 5 trials that randomized ≥1000 patients with any myocardial infarction undergoing PCI to bivalirudin versus heparin (MATRIX [Minimizing Adverse Hemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox], VALIDATE-SWEDEHEART [Bivalirudin Versus Heparin in ST-Segment and Non-ST-Segment Elevation Myocardial Infarction in Patients on Modern Antiplatelet Therapy in the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies Registry Trial], ISAR-REACT 4 [Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment 4], ACUITY [Acute Catheterization and Urgent Intervention Triage Strategy], and BRIGHT [Bivalirudin in Acute Myocardial Infarction vs Heparin and GPI Plus Heparin Trial]). The primary effectiveness and safety end points were 30-day all-cause mortality and serious bleeding. RESULTS: A total of 12 155 patients were randomized: 6040 to bivalirudin (52.3% with a post-PCI bivalirudin infusion), and 6115 to heparin (53.2% with planned glycoprotein IIb/IIIa inhibitor use). Thirty-day mortality was not significantly different between bivalirudin and heparin (1.2% versus 1.1%; adjusted odds ratio, 1.24 [95% CI, 0.86-1.79]; P=0.25). Cardiac mortality, reinfarction, and stent thrombosis rates were also not significantly different. Bivalirudin reduced serious bleeding (both access site-related and non-access site-related) compared with heparin (3.3% versus 5.5%; adjusted odds ratio, 0.59; 95% CI, 0.48-0.72; P<0.0001). Outcomes were consistent regardless of use of a post-PCI bivalirudin infusion or routine lycoprotein IIb/IIIa inhibitor use with heparin and during 1-year follow-up. CONCLUSIONS: In patients with non-ST-segment-elevation myocardial infarction undergoing PCI, procedural anticoagulation with bivalirudin and heparin did not result in significantly different rates of mortality or ischemic events, including stent thrombosis and reinfarction. Bivalirudin reduced serious bleeding compared with heparin arising both from the access site and nonaccess sites.
Assuntos
Infarto do Miocárdio , Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Trombose , Humanos , Heparina/efeitos adversos , Infarto do Miocárdio sem Supradesnível do Segmento ST/tratamento farmacológico , Anticoagulantes/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Hirudinas/efeitos adversos , Fragmentos de Peptídeos/efeitos adversos , Hemorragia/etiologia , Trombose/etiologia , Proteínas Recombinantes/efeitos adversos , Resultado do TratamentoRESUMO
BACKGROUND: Patients with diabetes have increased rates of major adverse cardiac events (MACEs). We hypothesized that this is explained by diabetes-associated differences in coronary plaque morphology and lipid content. METHODS: In PROSPECT II (Providing Regional Observations to Study Predictors of Events in the Coronary Tree), 898 patients with acute myocardial infarction with or without ST-segment elevation underwent 3-vessel quantitative coronary angiography and coregistered near-infrared spectroscopy and intravascular ultrasound imaging after successful percutaneous coronary intervention. Subsequent MACEs were adjudicated to either treated culprit lesions or untreated nonculprit lesions. This substudy stratified patients by diabetes status and assessed baseline culprit and nonculprit prevalence of high-risk plaque characteristics defined as maximum plaque burden ≥70% and maximum lipid core burden index ≥324.7. Separate covariate-adjusted multivariable models were performed to identify whether diabetes was associated with nonculprit lesion-related MACEs and high-risk plaque characteristics. RESULTS: Diabetes was present in 109 of 898 patients (12.1%). During a median 3.7-year follow-up, MACEs occurred more frequently in patients with versus without diabetes (20.1% versus 13.5% [odds ratio (OR), 1.94 (95% CI, 1.14-3.30)]), primarily attributable to increased risk of myocardial infarction related to culprit lesion restenosis (4.3% versus 1.1% [OR, 3.78 (95% CI, 1.12-12.77)]) and nonculprit lesion-related spontaneous myocardial infarction (9.3% versus 3.8% [OR, 2.74 (95% CI, 1.25-6.04)]). However, baseline prevalence of high-risk plaque characteristics was similar for patients with versus without diabetes concerning culprit (maximum plaque burden ≥70%: 90% versus 93%, P=0.34; maximum lipid core burden index ≥324.7: 66% versus 70%, P=0.49) and nonculprit lesions (maximum plaque burden ≥70%: 23% versus 22%, P=0.37; maximum lipid core burden index ≥324.7: 26% versus 24%, P=0.47). In multivariable models, diabetes was associated with MACEs in nonculprit lesions (adjusted OR, 2.47 [95% CI, 1.21-5.04]) but not with prevalence of high-risk plaque characteristics (adjusted OR, 1.21 [95% CI, 0.86-1.69]). CONCLUSIONS: Among patients with recent myocardial infarction, both treated and untreated lesions contributed to the diabetes-associated ≈2-fold increased MACE rate during the 3.7-year follow-up. Diabetes-related plaque characteristics that might underlie this increased risk were not identified by multimodality imaging. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02171065.
Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Diabetes Mellitus , Infarto do Miocárdio , Intervenção Coronária Percutânea , Placa Aterosclerótica , Humanos , Doença da Artéria Coronariana/complicações , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Síndrome Coronariana Aguda/terapia , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Infarto do Miocárdio/complicações , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/patologia , Angiografia Coronária/métodos , Intervenção Coronária Percutânea/efeitos adversos , Lipídeos , Valor Preditivo dos Testes , Resultado do TratamentoRESUMO
The core features of covalent organic frameworks (COFs) are crystallinity and porosity. However, the synthesis of single-crystal COFs with monomers of diverse reactivity and adjustment of their pore structures remain challenging. Here, we show that linkers that can react with a node to form single-crystal COFs can guide other linkers that form either COFs or amorphous polymers with the node to gain single-crystal COFs with mixed components, which are homogeneous on the unit cell scale with controlled ratios. With the linker-guided crystal growth method, we created nine types of single-crystal COFs with up to nine different components, which are more complex than any known crystal. The structure of the crystal adapted approximately to that of the main component, and its pore volume could be expanded up to 8.8%. Different components lead to complex and diverse pore structures and offer the possibilities to gain positive synergies, as exemplified by a bicomponent COF with 2200 and 733% SO2 uptake capacity of that of the two pure-component counterparts at 298 K and 0.002 bar. The selectivity for separation of SO2/CO2 ranges from 1230 to 4247 for flue gas based on ideal adsorbed solution theory, recording porous crystals. The bicomponent COF also exhibits a 1300% retention time of its pure-component counterparts for SO2 in a dynamic column breakthrough experiment for deep desulfurization.
RESUMO
The increase in the detection rate of synchronous multiple primary lung cancer (MPLC) has posed remarkable clinical challenges due to the limited understanding of its pathogenesis and molecular features. Here, comprehensive comparisons of genomic and immunologic features between MPLC and solitary lung cancer nodule (SN), as well as different lesions of the same patient, were performed. Compared with SN, MPLC displayed a lower rate of EGFR mutation but higher rates of BRAF, MAP2K1, and MTOR mutation, which function exactly in the upstream and downstream of the same signaling pathway. Considerable heterogeneity in T cell receptor (TCR) repertoire exists among not only different patients but also among different lesions of the same patient. Invasive lesions of MPLC exhibited significantly higher TCR diversity and lower TCR expansion than those of SN. Intriguingly, different lesions of the same patient always shared a certain proportion of TCR clonotypes. Significant clonal expansion could be observed in shared TCR clonotypes, particularly in those existing in all lesions of the same patient. In conclusion, this study provided evidences of the distinctive mutational landscape, activation of oncogenic signaling pathways, and TCR repertoire in MPLC as compared with SN. The significant clonal expansion of shared TCR clonotypes demonstrated the existence of immune commonality among different lesions of the same patient and shed new light on the individually tailored precision therapy for MPLC.
Assuntos
Neoplasias Pulmonares , Mutação , Neoplasias Primárias Múltiplas , Receptores de Antígenos de Linfócitos T , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Neoplasias Primárias Múltiplas/imunologia , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , IdosoRESUMO
Genetic targeting (e.g., gene knockout and tagging) based on polymerase chain reaction (PCR) is a simple yet powerful approach for studying gene functions. Although originally developed in classic budding and fission yeast models, the same principle applies to other eukaryotic systems with efficient homologous recombination. One-step PCR-based genetic targeting is conventionally used but the sizes of the homologous arms that it generates for recombination-mediated genetic targeting are usually limited. Alternatively, gene targeting can also be performed via fusion PCR, which can create homologous arms that are orders of magnitude larger, therefore substantially increasing the efficiency of recombination-mediated genetic targeting. Here, we present GetPrimers (https://www.evomicslab.org/app/getprimers/), a generalized computational framework and web tool to assist automatic targeting and verification primer design for both one-step PCR-based and fusion PCR-based genetic targeting experiments. Moreover, GetPrimers by design runs for any given genetic background of any species with full genome scalability. Therefore, GetPrimers is capable of empowering high-throughput functional genomic assays at multipopulation and multispecies levels. Comprehensive experimental validations have been performed for targeting and verification primers designed by GetPrimers across multiple organism systems and experimental setups. We anticipate GetPrimers to become a highly useful and popular tool to facilitate easy and standardized gene modification across multiple systems.
Assuntos
Marcação de Genes , Schizosaccharomyces , Recombinação Homóloga , Técnicas de Inativação de Genes , Sequência de Bases , Schizosaccharomyces/genética , Reação em Cadeia da PolimeraseRESUMO
BACKGROUND: WD repeat domain 12 (WDR12) plays a crucial role in the ribosome biogenesis pathway. However, its biological function in colorectal cancer (CRC) remains poorly understood. Therefore, this study aims to investigate the roles of WDR12 in the occurrence and progression of CRC, as well as its underlying mechanisms. METHODS: The expression of WDR12 was assessed through The Cancer Genome Atlas (TCGA) and the Human Protein Atlas (HPA) database. Functional experiments including Celigo assay, MTT assay, and Caspase-3/7 assay were conducted to validate the role of WDR12 in the malignant progression of CRC. Additionally, mRNA chip-sequencing and ingenuity pathway analysis (IPA) were performed to identify the molecular mechanism. RESULTS: WDR12 expression was significantly upregulated in CRC tissues compared to normal colorectal tissues. Knockdown of WDR12 reduced proliferation and promoted apoptosis of CRC cell lines in vitro and in vivo experiments. Furthermore, WDR12 expression had a significantly inverse association with diseases and functions, including cancer, cell cycle, DNA replication, recombination, cellular growth, proliferation and repair, as revealed by IPA analysis of mRNA chip-sequencing data. Moreover, the activation of cell cycle checkpoint kinases proteins in the cell cycle checkpoint control signaling pathway was enriched in the WDR12 knockdown CRC cell lines. Additionally, downregulation of rac family small GTPase 1 (RAC1) occurred upon WDR12 knockdown, thereby facilitating the proliferation and anti-apoptosis of CRC cells. CONCLUSION: Our study demonstrates that the WDR12/RAC1 axis promotes tumor progression in CRC. Therefore, WDR12 may serve as a novel oncogene and a potential target for individualized therapy in CRC. These findings provide an experimental foundation for the clinical development of drugs targeting the WDR12/RAC1 axis.
RESUMO
Codon usage bias is a fundamental feature of all genomes and plays an important role in determining gene expression levels. The codon usage was thought to influence gene expression mainly due to its impact on translation. Recently, however, codon usage was shown to affect transcription of fungal and mammalian genes, indicating the existence of a gene regulatory phenomenon with unknown mechanism. In Neurospora, codon usage biases strongly correlate with mRNA levels genome-wide, and here we show that the correlation between codon usage and RNA levels is maintained in the nucleus. In addition, codon optimality is tightly correlated with both total and nuclear RNA levels, suggesting that codon usage broadly influences mRNA levels through transcription in a translation-independent manner. A large-scale RNA sequencing-based genetic screen in Neurospora identified 18 candidate factors that when deleted decreased the genome-wide correlation between codon usage and RNA levels and reduced the codon usage effect on gene expression. Most of these factors, such as the H3K36 methyltransferase, are chromatin regulators or transcription factors. Together, our results suggest that the transcriptional effect of codon usage is mediated by multiple transcriptional regulatory mechanisms.
Assuntos
Uso do Códon/genética , Neurospora crassa/genética , RNA Mensageiro/biossíntese , Transcrição Gênica , Cromatina/genética , Regulação Fúngica da Expressão Gênica/genética , Genoma Fúngico/genética , RNA Mensageiro/genéticaRESUMO
In eukaryotes, antisense transcription can regulate sense transcription by induction of epigenetic modifications. We showed previously that antisense transcription triggers Dicer-independent siRNA (disiRNA) production and disiRNA locus DNA methylation (DLDM) in Neurospora crassa Here we show that the conserved exonuclease ERI-1 (enhanced RNAi-1) is a critical component in this process. Antisense transcription and ERI-1 binding to target RNAs are necessary and sufficient to trigger DLDM. Convergent transcription causes stalling of RNA polymerase II during transcription, which permits ERI-1 to bind nascent RNAs in the nucleus and recruit a histone methyltransferase complex that catalyzes chromatin modifications. Furthermore, we show that, in the cytoplasm, ERI-1 targets hundreds of transcripts from loci without antisense transcription to regulate RNA stability. Together, our results demonstrate a critical role for transcription kinetics in long noncoding RNA-mediated epigenetic modifications and identify ERI-1 as an important regulator of cotranscriptional gene silencing and post-transcriptional RNA metabolism.
Assuntos
Regulação Fúngica da Expressão Gênica , Inativação Gênica , Genes Fúngicos/genética , Neurospora crassa/genética , Núcleo Celular/metabolismo , Citosol/metabolismo , Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Exonucleases/metabolismo , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Mutação , Ligação Proteica , Estabilidade de RNA/genéticaRESUMO
Drought is one of the major abiotic stresses with a severe negative impact on maize production globally. Understanding the genetic architecture of drought tolerance in maize is a crucial step towards the breeding of drought-tolerant varieties and a targeted exploitation of genetic resources. In this study, 511 quantitative trait loci (QTL) related to grain yield components, flowering time, and plant morphology under drought conditions, as well as drought tolerance index were collected from 27 published studies and then projected on the IBM2 2008 Neighbors reference map for meta-analysis. In total, 83 meta-QTL (MQTL) associated with drought tolerance in maize were identified, of which 20 were determined as core MQTL. The average confidence interval of MQTL was strongly reduced compared to that of the previously published QTL. Nearly half of the MQTL were confirmed by co-localized marker-trait associations from genome-wide association studies. Based on the alignment of rice proteins related to drought tolerance, 63 orthologous genes were identified near the maize MQTL. Furthermore, 583 candidate genes were identified within the 20 core MQTL regions and maize-rice homologous genes. Based on KEGG analysis of candidate genes, plant hormone signaling pathways were found to be significantly enriched. The signaling pathways can have direct or indirect effects on drought tolerance and also interact with other pathways. In conclusion, this study provides novel insights into the genetic and molecular mechanisms of drought tolerance in maize towards a more targeted improvement of this important trait in breeding.
Assuntos
Resistência à Seca , Locos de Características Quantitativas , Zea mays , Mapeamento Cromossômico , Genes de Plantas , Estudo de Associação Genômica Ampla , Fenótipo , Estresse Fisiológico/genética , Zea mays/genética , Zea mays/fisiologiaRESUMO
Due to the enormous chemical and structural diversities and designable properties and functionalities, covalent organic frameworks (COFs) hold great promise as tailored materials for industrial applications in electronics, biology, and energy technologies. They were typically obtained as partially crystalline materials, although a few single-crystal three-dimensional (3D) COFs have been obtained recently with structures probed by diffraction techniques. However, it remains challenging to grow single-crystal COFs with controlled morphology and to elucidate the local structures of 3D COFs, imposing severe limitations on the applications and understanding of the local structure-property correlations. Herein, we develop a method for designed growth of five types of single crystalline flakes of 3D COFs with controlled morphology, front crystal facets, and defined edge structures as well as surface chemistry using surfactants that can be self-assembled into layered structures to confine crystal growth in water. The flakes enable direct observation of local structures including monomer units, pore structure, edge structure, grain boundary, and lattice distortion of 3D COFs as well as gradually curved surfaces in kinked but single crystalline 3D COFs with a resolution of up to â¼1.7 Å. In comparison with flakes of two-dimensional crystals, the synthesized flakes show much higher chemical, mechanical, and thermal stability.
RESUMO
OBJECTIVE: T-cell receptor (TCR) repertoire diversity is getting increasing attention as a predictive biomarker in cancer patients. However, the characteristics of the TCR together with its predictive significance for high grade serous ovarian cancer (HGSOC) patients receiving poly (ADP-ribose) polymerase inhibitor (PARPi) maintenance therapy remain unknown. METHODS: Twenty-seven patients with HGSOC were analyzed including 22 patients receiving PARPi maintenance therapy and 5 untreated patients as control. Peripheral blood samples were collected for TCR sequencing at baseline as well as one month and three months after the exposure to PARPi. To determine whether TCR diversity was related to PARPi efficacy, we compared the TCR repertoire between patients who had received PARPi and those who had not. RESULTS: For patients receiving PARPi treatment or not, we evaluated changes in clone abundance during PARPi maintenance and the similarity of the TCR repertoire before and after the treatment. The results revealed that patients receiving PARPi had TCR repertoires that were more stable than those of untreated cases. We next correlated TCR diversity with the efficacy of PARPi in the treatment group. The rising trend of TCR diversity after three months with PARPi treatment was associated with a longer PFS (21.7 vs 7.4 months, hazard ratio = 0.19, p < 0.001) and a better response to PARPi (91.7% vs 25.0%, p = 0.004). Furthermore, we discovered that the primary characteristic with predictive value for the effectiveness of PARPi is the considerable reduction of the high-frequency T cell clones. CONCLUSION: We suggested that the circulating TCR diversity could be a potential predictive biomarker for PARPi maintenance therapy in HGSOC.
Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Antineoplásicos/uso terapêutico , Biomarcadores , Receptores de Antígenos de Linfócitos TRESUMO
OBJECTIVES: To evaluate the value of time-serial CT radiomics features in predicting progression-free survival (PFS) for lung adenocarcinoma (LUAD) patients after epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) therapy. MATERIALS AND METHODS: LUAD patients treated with EGFR-TKIs were retrospectively included from three independent institutes and divided into training and validation cohorts. Intratumoral and peritumoral features were extracted from time-serial non-contrast chest CT (including pre-therapy and first follow-up images); moreover, the percentage variation per unit time (day) was introduced to adjust for the different follow-up periods of each patient. Test-retest was performed to exclude irreproducible features, while the Boruta algorithm was used to select critical radiomics features. Radiomics signatures were constructed with random forest survival models in the training cohort and compared against baseline clinical characteristics through Cox regression and nonparametric testing of concordance indices (C-indices). RESULTS: The training cohort included 131 patients (74 women, 56.5%) from one institute and the validation cohort encompassed 41 patients (24 women, 58.5%) from two other institutes. The optimal signature contained 10 features and 7 were unit time feature variations. The comprehensive radiomics model outperformed the pre-therapy clinical characteristics in predicting PFS (training: 0.78, 95% CI: [0.72, 0.84] versus 0.55, 95% CI: [0.49, 0.62], p < 0.001; validation: 0.72, 95% CI: [0.60, 0.84] versus 0.54, 95% CI: [0.42, 0.66], p < 0.001). CONCLUSION: Radiomics signature derived from time-serial CT images demonstrated optimal prognostic performance of disease progression. This dynamic imaging biomarker holds the promise of monitoring treatment response and achieving personalized management. KEY POINTS: ⢠The intrinsic tumor heterogeneity can be highly dynamic under the therapeutic effect of EGFR-TKI treatment, and the inevitable development of drug resistance may disrupt the duration of clinical benefit. Decision-making remained challenging in practice to detect the emergence of acquired resistance during the early response phase. ⢠Time-serial CT-based radiomics signature integrating intra- and peritumoral features offered the potential to predict progression-free survival for LUAD patients treated with EGFR-TKIs. ⢠The dynamic imaging signature allowed for prognostic risk stratification.
Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Feminino , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Prognóstico , Estudos Retrospectivos , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Tomografia Computadorizada por Raios X/métodos , Receptores ErbB , Medição de RiscoRESUMO
Codon usage bias is a universal feature of eukaryotic and prokaryotic genomes and has been proposed to regulate translation efficiency, accuracy, and protein folding based on the assumption that codon usage affects translation dynamics. The roles of codon usage in translation, however, are not clear and have been challenged by recent ribosome profiling studies. Here we used a Neurospora cell-free translation system to directly monitor the velocity of mRNA translation. We demonstrated that the preferred codons enhance the rate of translation elongation, whereas non-optimal codons slow elongation. Codon usage also controls ribosome traffic on mRNA. These conclusions were supported by ribosome profiling results in vitro and in vivo with template mRNAs designed to increase the signal-to-noise ratio. Finally, we demonstrate that codon usage regulates protein function by affecting co-translational protein folding. These results resolve a long-standing fundamental question and suggest the existence of a codon usage code for protein folding.
Assuntos
Códon/genética , Elongação Traducional da Cadeia Peptídica , Dobramento de Proteína , Animais , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Luciferases de Vaga-Lume/química , Luciferases de Vaga-Lume/genética , Luciferases de Vaga-Lume/metabolismo , Modelos Moleculares , Neurospora crassa/genética , Neurospora crassa/metabolismo , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ribossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , TemperaturaRESUMO
Codon usage bias is a universal feature of all genomes and plays an important role in regulating protein expression levels. Modification of adenosine to inosine at the tRNA anticodon wobble position (I34) by adenosine deaminases (ADATs) is observed in all eukaryotes and has been proposed to explain the correlation between codon usage and tRNA pool. However, how the tRNA pool is affected by I34 modification to influence codon usage-dependent gene expression is unclear. Using Neurospora crassa as a model system, by combining molecular, biochemical and bioinformatics analyses, we show that silencing of adat2 expression severely impaired the I34 modification levels for the ADAT-related tRNAs, resulting in major ADAT-related tRNA profile changes and reprogramming of translation elongation kinetics on ADAT-related codons. adat2 silencing also caused genome-wide codon usage-biased ribosome pausing on mRNAs and proteome landscape changes, leading to selective translational repression or induction of different mRNAs. The induced expression of CPC-1, the Neurospora ortholog of yeast GCN4p, mediates the transcriptional response after adat2 silencing and amino acid starvation. Together, our results demonstrate that the tRNA I34 modification by ADAT plays a major role in driving codon usage-biased translation to shape proteome landscape.
Assuntos
Anticódon/genética , Uso do Códon , Elongação Traducional da Cadeia Peptídica/genética , Proteoma/genética , RNA de Transferência de Arginina/genética , Adenosina/metabolismo , Adenosina Desaminase/metabolismo , Anticódon/metabolismo , Biologia Computacional , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Inosina/metabolismo , Neurospora crassa/genética , RNA de Transferência de Arginina/metabolismo , Ribossomos/metabolismoRESUMO
BACKGROUND: Breast cancer is the most common cancer in women worldwide. More than 70% of breast cancers are estrogen receptor (ER) alpha positive. Compared with ER alpha-negative breast cancer, which is more aggressive and has a shorter survival time, ER alpha-positive breast cancer could benefit from endocrine therapy. Selective estrogen receptor modulators, such as tamoxifen, are widely used in endocrine therapy. Approximately half of ER alpha-positive breast cancer patients will eventually develop endocrine resistance, making it a major clinical challenge in therapy. Thus, decoding the throughput of estrogen signaling, including the control of ER alpha expression and stability, is critical for the improvement of breast cancer therapeutics. METHODS: TRIM3 and ER alpha protein expression levels were measured by western blotting, while the mRNA levels of ER alpha target genes were measured by RT-PCR. A CCK-8 assay was used to measure cell viability. RNA sequencing data were analyzed by Ingenuity Pathway Analysis. Identification of ER alpha signaling activity was accomplished with luciferase assays, RT-PCR and western blotting. Protein stability assays and ubiquitin assays were used to detect ER alpha protein degradation. Ubiquitin-based immunoprecipitation assays were used to detect the specific ubiquitination modification on the ER alpha protein. RESULTS: In our current study, we found that TRIM3, an E3 ligase, can promote ER alpha signaling activity and breast cancer progression. TRIM3 depletion inhibits breast cancer cell proliferation and migration, while unbiased RNA sequencing data indicated that TRIM3 is required for the activity of estrogen signaling on the -genome-wide scale. The immunoprecipitation assays indicated that TRIM3 associates with ER alpha and promotes its stability, possibly by inducing K63-linked polyubiquitination of ER alpha. In conclusion, our data implicate a nongenomic mechanism by which TRIM3 stabilizes the ER alpha protein to control ER alpha target gene expression linked to breast cancer progression. CONCLUSION: Our study provides a novel posttranslational mechanism in estrogen signaling. Modulation of TRIM3 expression or function could be an interesting approach for breast cancer treatment. Video abstract.
Assuntos
Neoplasias da Mama , Proteínas de Transporte , Neoplasias da Mama/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Estrogênios , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Tamoxifeno/farmacologia , Ubiquitina/metabolismoRESUMO
The purpose of this study was to evaluate the neuroprotective effect of leptin on a non-human primate model of cerebral ischemia. A total of 39 Guangxi macaques were used to establish the primate cerebral-ischemia model. HE staining was used to evaluated the pathological changes. Moreover, magnetic resonance imaging was used for the detection of embolic area. The measurements of behavior observation and cerebral infarction area were also performed. They all received autologous thrombus operation. Furthermore, western blot and RT-PCR were also used to detect the protein and mRNA expression levels of apoptosis-related factors. Our results showed that leptin could reduce the volume of cerebral infarction by about 35%. Behavioral defects can be significantly improved. In addition, mid-term and long-term behavioral deficiencies had been significantly improved by leptin. Moreover, leptin significantly decreased the expression levels of caspase-3 and Bax, and increased the expression levels of Bcl-2. In conclusion, leptin has neuroprotective effects on cerebral ischemia by effectively reducing the volume of cerebral infarction.
Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/metabolismo , Leptina , Encéfalo , China , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/metabolismo , Infarto Cerebral/patologia , Apoptose , Primatas/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 3/farmacologiaRESUMO
Bacillus Calmette-Guérin polysaccharide and nucleic acid (BCG-PSN), extracted from Mycobacterium bovis, is an immunoregulatory medicine commonly used in clinic. However, the structural characteristics and potential pharmacological efficacy of the polysaccharides from BCG-PSN remain unclear. Herein, two polysaccharides (BCG-1 and BCG-2) were purified and their structures were characterized. Monosaccharide composition analysis combined with methylation analysis and NMR data indicated that BCG-1 and BCG-2 were an α-D-(1â4)-mannan with (1â2)-linked branches, and an α-D-(1â4)-glucan with (1â6)-linked branches, respectively. Herein, the mannan from BCG-PSN was first reported. Bioactivity assays showed that BCG-1 and BCG-2 dose-dependently and potently increased the production of inflammatory mediators (NO, TNF-α, IL-6, IL-1ß, and IL-10), as well as their mRNA expressions in RAW264.7 cells; both have similar or stronger effects compared with BCG-PSN injection. These data suggest that BCG-1 and BCG-2 are very likely the active ingredients of BCG-PSN.
Assuntos
Mycobacterium bovis , Adjuvantes Imunológicos , Vacina BCG , Mananas/farmacologia , Mycobacterium bovis/química , Polissacarídeos/farmacologiaRESUMO
Developing extra safety encryption technologies to prevent information leakage and combat fakes is in high demand but is challenging. Herein, we propose a "double lock" strategy based on both lower critical solution temperature (LCST) and upper critical solution temperature (UCST) polymer hydrogels for information camouflage and multilevel encryption. Two types of hydrogels were synthesized by the method of random copolymerization. The number of -CO-NH2 groups in the network structure of the hydrogels changed the enthalpic or entropic thermo-responsive hydrogels, and ultimately precisely controlled their phase transition temperature. The crosslink density of the polymer hydrogels governs the diffusion kinetics, resulting in a difference in the time for their color change. The combination of multiple LCST and UCST hydrogels in one label realized information encryption and dynamic information identification in the dimensions of both time and temperature. This work is highly interesting for the fields of information encryption, anti-counterfeiting, and smart responsive materials.