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1.
Cell ; 186(24): 5363-5374.e16, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37972591

RESUMO

Cav1.2 channels play crucial roles in various neuronal and physiological processes. Here, we present cryo-EM structures of human Cav1.2, both in its apo form and in complex with several drugs, as well as the peptide neurotoxin calciseptine. Most structures, apo or bound to calciseptine, amlodipine, or a combination of amiodarone and sofosbuvir, exhibit a consistent inactivated conformation with a sealed gate, three up voltage-sensing domains (VSDs), and a down VSDII. Calciseptine sits on the shoulder of the pore domain, away from the permeation path. In contrast, when pinaverium bromide, an antispasmodic drug, is inserted into a cavity reminiscent of the IFM-binding site in Nav channels, a series of structural changes occur, including upward movement of VSDII coupled with dilation of the selectivity filter and its surrounding segments in repeat III. Meanwhile, S4-5III merges with S5III to become a single helix, resulting in a widened but still non-conductive intracellular gate.


Assuntos
Canais de Cálcio Tipo L , Venenos Elapídicos , Humanos , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/metabolismo , Neurotoxinas , Domínios Proteicos , Microscopia Crioeletrônica
2.
Cell ; 185(25): 4801-4810.e13, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36417914

RESUMO

Drug-drug interaction of the antiviral sofosbuvir and the antiarrhythmics amiodarone has been reported to cause fatal heartbeat slowing. Sofosbuvir and its analog, MNI-1, were reported to potentiate the inhibition of cardiomyocyte calcium handling by amiodarone, which functions as a multi-channel antagonist, and implicate its inhibitory effect on L-type Cav channels, but the molecular mechanism has remained unclear. Here we present systematic cryo-EM structural analysis of Cav1.1 and Cav1.3 treated with amiodarone or sofosbuvir alone, or sofosbuvir/MNI-1 combined with amiodarone. Whereas amiodarone alone occupies the dihydropyridine binding site, sofosbuvir is not found in the channel when applied on its own. In the presence of amiodarone, sofosbuvir/MNI-1 is anchored in the central cavity of the pore domain through specific interaction with amiodarone and directly obstructs the ion permeation path. Our study reveals the molecular basis for the physical, pharmacodynamic interaction of two drugs on the scaffold of Cav channels.


Assuntos
Amiodarona , Sofosbuvir , Sofosbuvir/efeitos adversos , Amiodarona/farmacologia , Antivirais/farmacologia , Miócitos Cardíacos/metabolismo , Sítios de Ligação , Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo
3.
Cell ; 184(4): 1081-1097.e19, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33606978

RESUMO

Mutations in DNA damage response (DDR) genes endanger genome integrity and predispose to cancer and genetic disorders. Here, using CRISPR-dependent cytosine base editing screens, we identify > 2,000 sgRNAs that generate nucleotide variants in 86 DDR genes, resulting in altered cellular fitness upon DNA damage. Among those variants, we discover loss- and gain-of-function mutants in the Tudor domain of the DDR regulator 53BP1 that define a non-canonical surface required for binding the deubiquitinase USP28. Moreover, we characterize variants of the TRAIP ubiquitin ligase that define a domain, whose loss renders cells resistant to topoisomerase I inhibition. Finally, we identify mutations in the ATM kinase with opposing genome stability phenotypes and loss-of-function mutations in the CHK2 kinase previously categorized as variants of uncertain significance for breast cancer. We anticipate that this resource will enable the discovery of additional DDR gene functions and expedite studies of DDR variants in human disease.


Assuntos
Dano ao DNA , Edição de Genes , Testes Genéticos , Sequência de Aminoácidos , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sequência de Bases , Sistemas CRISPR-Cas/genética , Camptotecina/farmacologia , Linhagem Celular , Dano ao DNA/genética , Reparo do DNA/genética , Feminino , Humanos , Mutação/genética , Fenótipo , Ligação Proteica , Domínios Proteicos , RNA Guia de Cinetoplastídeos/genética , Inibidores da Topoisomerase/farmacologia , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/química , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Ubiquitina Tiolesterase/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
4.
Nat Methods ; 21(6): 1023-1032, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38664529

RESUMO

Addressing interfacial effects during specimen preparation in cryogenic electron microscopy remains challenging. Here we introduce ESI-cryoPrep, a specimen preparation method based on electrospray ionization in native mass spectrometry, designed to alleviate issues associated with protein denaturation or preferred orientation induced by macromolecule adsorption at interfaces. Through fine-tuning spraying parameters, we optimized protein integrity preservation and achieved the desired ice thickness for analyzing target macromolecules. With ESI-cryoPrep, we prepared high-quality cryo-specimens of five proteins and obtained three-dimensional reconstructions at near-atomic resolution. Our findings demonstrate that ESI-cryoPrep effectively confines macromolecules within the middle of the thin layer of amorphous ice, facilitating the preparation of blotting-free vitreous samples. The protective mechanism, characterized by the uneven distribution of charged biomolecules of varying sizes within charged droplets, prevents the adsorption of target biomolecules at air-water or graphene-water interfaces, thereby avoiding structural damage to the protein particles or the introduction of dominant orientation issues.


Assuntos
Microscopia Crioeletrônica , Manejo de Espécimes , Espectrometria de Massas por Ionização por Electrospray , Microscopia Crioeletrônica/métodos , Manejo de Espécimes/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Proteínas/química , Humanos , Substâncias Macromoleculares/química
5.
Circ Res ; 134(2): 203-222, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38166414

RESUMO

BACKGROUND: Angiogenesis, which plays a critical role in embryonic development and tissue repair, is controlled by a set of angiogenic signaling pathways. As a TF (transcription factor) belonging to the basic helix-loop-helix family, HEY (hairy/enhancer of split related with YRPW motif)-1 (YRPW motif, abbreviation of 4 highly conserved amino acids in the motif) has been identified as a key player in developmental angiogenesis. However, the precise mechanisms underlying HEY1's actions in angiogenesis remain largely unknown. Our previous studies have suggested a potential role for posttranslational SUMOylation in the dynamic regulation of vascular development and organization. METHODS: Immunoprecipitation, mass spectrometry, and bioinformatics analysis were used to determine the biochemical characteristics of HEY1 SUMOylation. The promoter-binding capability of HEY1 was determined by chromatin immunoprecipitation, dual luciferase, and electrophoretic mobility shift assays. The dimerization pattern of HEY1 was determined by coimmunoprecipitation. The angiogenic capabilities of endothelial cells were assessed by CCK-8 (cell counting kit-8), 5-ethynyl-2-deoxyuridine staining, wound healing, transwell, and sprouting assays. Embryonic and postnatal vascular growth in mouse tissues, matrigel plug assay, cutaneous wound healing model, oxygen-induced retinopathy model, and tumor angiogenesis model were used to investigate the angiogenesis in vivo. RESULTS: We identified intrinsic endothelial HEY1 SUMOylation at conserved lysines by TRIM28 (tripartite motif containing 28) as the unique E3 ligase. Functionally, SUMOylation facilitated HEY1-mediated suppression of angiogenic RTK (receptor tyrosine kinase) signaling and angiogenesis in primary human endothelial cells and mice with endothelial cell-specific expression of wild-type HEY1 or a SUMOylation-deficient HEY1 mutant. Mechanistically, SUMOylation facilitates HEY1 homodimer formation, which in turn preserves HEY1's DNA-binding capability via recognition of E-box promoter elements. Therefore, SUMOylation maintains HEY1's function as a repressive TF controlling numerous angiogenic genes, including RTKs and Notch pathway components. Proangiogenic stimuli induce HEY1 deSUMOylation, leading to heterodimerization of HEY1 with HES (hairy and enhancer of split)-1, which results in ineffective DNA binding and loss of HEY1's angiogenesis-suppressive activity. CONCLUSIONS: Our findings demonstrate that reversible HEY1 SUMOylation is a molecular mechanism that coordinates endothelial angiogenic signaling and angiogenesis, both in physiological and pathological milieus, by fine-tuning the transcriptional activity of HEY1. Specifically, SUMOylation facilitates the formation of the HEY1 transcriptional complex and enhances its DNA-binding capability in endothelial cells.


Assuntos
Células Endoteliais , Sumoilação , Animais , Humanos , Camundongos , Angiogênese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , DNA/metabolismo , Células Endoteliais/metabolismo
6.
Proc Natl Acad Sci U S A ; 120(5): e2220578120, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36696443

RESUMO

Voltage-gated sodium channel Nav1.6 plays a crucial role in neuronal firing in the central nervous system (CNS). Aberrant function of Nav1.6 may lead to epilepsy and other neurological disorders. Specific inhibitors of Nav1.6 thus have therapeutic potentials. Here we present the cryo-EM structure of human Nav1.6 in the presence of auxiliary subunits ß1 and fibroblast growth factor homologous factor 2B (FHF2B) at an overall resolution of 3.1 Å. The overall structure represents an inactivated state with closed pore domain (PD) and all "up" voltage-sensing domains. A conserved carbohydrate-aromatic interaction involving Trp302 and Asn326, together with the ß1 subunit, stabilizes the extracellular loop in repeat I. Apart from regular lipids that are resolved in the EM map, an unprecedented Y-shaped density that belongs to an unidentified molecule binds to the PD, revealing a potential site for developing Nav1.6-specific blockers. Structural mapping of disease-related Nav1.6 mutations provides insights into their pathogenic mechanism.


Assuntos
Canais de Sódio Disparados por Voltagem , Humanos , Microscopia Crioeletrônica , Canais de Sódio Disparados por Voltagem/genética , Canais de Sódio Disparados por Voltagem/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.7/química , Canal de Sódio Disparado por Voltagem NAV1.6/genética , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Canal de Sódio Disparado por Voltagem NAV1.5 , Canal de Sódio Disparado por Voltagem NAV1.2
7.
Proc Natl Acad Sci U S A ; 120(33): e2306130120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549255

RESUMO

Electronic detection of DNA oligomers offers the promise of rapid, miniaturized DNA analysis across various biotechnological applications. However, known all-electrical methods, which solely rely on measuring electrical signals in transducers during probe-target DNA hybridization, are prone to nonspecific electrostatic and electrochemical interactions, subsequently limiting their specificity and detection limit. Here, we demonstrate a nanomechanoelectrical approach that delivers ultra-robust specificity and a 100-fold improvement in detection limit. We drive nanostructural DNA strands tethered to a graphene transistor to oscillate in an alternating electric field and show that the transistor-current spectra are characteristic and indicative of DNA hybridization. We find that the inherent difference in pliability between unpaired and paired DNA strands leads to the spectral characteristics with minimal influence from nonspecific electrostatic and electrochemical interactions, resulting in high selectivity and sensitivity. Our results highlight the potential of high-performance DNA analysis based on miniaturized all-electronic settings.


Assuntos
Técnicas Biossensoriais , Grafite , DNA/química , Hibridização de Ácido Nucleico , Sondas de DNA/química , Grafite/química , Hibridização Genética , Técnicas Biossensoriais/métodos
8.
Proc Natl Acad Sci U S A ; 120(41): e2309773120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782796

RESUMO

Voltage-gated sodium (Nav) channels govern membrane excitability, thus setting the foundation for various physiological and neuronal processes. Nav channels serve as the primary targets for several classes of widely used and investigational drugs, including local anesthetics, antiepileptic drugs, antiarrhythmics, and analgesics. In this study, we present cryogenic electron microscopy (cryo-EM) structures of human Nav1.7 bound to two clinical drugs, riluzole (RLZ) and lamotrigine (LTG), at resolutions of 2.9 Å and 2.7 Å, respectively. A 3D EM reconstruction of ligand-free Nav1.7 was also obtained at 2.1 Å resolution. RLZ resides in the central cavity of the pore domain and is coordinated by residues from repeats III and IV. Whereas one LTG molecule also binds to the central cavity, the other is found beneath the intracellular gate, known as site BIG. Therefore, LTG, similar to lacosamide and cannabidiol, blocks Nav channels via a dual-pocket mechanism. These structures, complemented with docking and mutational analyses, also explain the structure-activity relationships of the LTG-related linear 6,6 series that have been developed for improved efficacy and subtype specificity on different Nav channels. Our findings reveal the molecular basis for these drugs' mechanism of action and will aid the development of novel antiepileptic and pain-relieving drugs.


Assuntos
Canabidiol , Canais de Sódio Disparados por Voltagem , Humanos , Anticonvulsivantes/farmacologia , Lamotrigina/farmacologia , Sódio/metabolismo , Canais de Sódio Disparados por Voltagem/química
9.
Am J Hum Genet ; 109(2): 282-298, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35026164

RESUMO

To understand the genetic contribution to primary pediatric cardiomyopathy, we performed exome sequencing in a large cohort of 528 children with cardiomyopathy. Using clinical interpretation guidelines and targeting genes implicated in cardiomyopathy, we identified a genetic cause in 32% of affected individuals. Cardiomyopathy sub-phenotypes differed by ancestry, age at diagnosis, and family history. Infants < 1 year were less likely to have a molecular diagnosis (p < 0.001). Using a discovery set of 1,703 candidate genes and informatic tools, we identified rare and damaging variants in 56% of affected individuals. We see an excess burden of damaging variants in affected individuals as compared to two independent control sets, 1000 Genomes Project (p < 0.001) and SPARK parental controls (p < 1 × 10-16). Cardiomyopathy variant burden remained enriched when stratified by ancestry, variant type, and sub-phenotype, emphasizing the importance of understanding the contribution of these factors to genetic architecture. Enrichment in this discovery candidate gene set suggests multigenic mechanisms underlie sub-phenotype-specific causes and presentations of cardiomyopathy. These results identify important information about the genetic architecture of pediatric cardiomyopathy and support recommendations for clinical genetic testing in children while illustrating differences in genetic architecture by age, ancestry, and sub-phenotype and providing rationale for larger studies to investigate multigenic contributions.


Assuntos
Cardiomiopatia Dilatada/genética , Exoma , Regulação da Expressão Gênica , Genótipo , Padrões de Herança , Idade de Início , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/patologia , Estudos de Casos e Controles , Criança , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Testes Genéticos , Variação Genética , Humanos , Masculino , Fenótipo , Guias de Prática Clínica como Assunto , Sequenciamento do Exoma
10.
J Virol ; : e0125124, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39412258

RESUMO

Zika virus (ZIKV) remains a significant public health threat worldwide. A number of adaptive mutations have accumulated within the genome of ZIKV during global transmission, some of which have been linked to specific phenotypes. ZIKV maintains an alternating cycle of replication between mosquitoes and vertebrate hosts, but the role of mosquito-specific adaptive mutations in ZIKV has not been well investigated. In this study, we demonstrated that serial passaging of ZIKV in mosquito Aag2 cells led to the emergence of critical amino acid substitutions, including A94V in the prM protein and V153D and H401Y in the E protein. Further characterization via reverse genetics revealed that the H401Y substitution in the E protein did not augment viral replication in mosquitoes but significantly enhanced neurovirulence and lethality compared with those of the wild-type (WT) virus in mice. More importantly, the H401Y mutant maintained its virulence phenotype in mice after propagation in mosquitoes in mosquito-mouse cycle model. In particular, recombinant ZIKV harboring the H401Y substitution showed enhanced competitive fitness over WT ZIKV in various mammalian cells and mouse brains, but not in mosquito cells. Notably, the H401Y substitution in the ZIKV E protein has been detected in recent isolates derived from both mosquitoes and humans in Asia and the Americas. In summary, our findings not only identify a novel virulence determinant of ZIKV but also highlight the complexity of the relationship between the evolution of vector-borne viruses and their clinical outcome in nature. IMPORTANCE: Zika virus (ZIKV) is an important arbovirus with a global impact. Experimental evolution by serial passaging of ZIKV in susceptible cells has led to the identification of a panel of critical amino acid substitutions with specific functions. Herein, we identified a mosquito cell-derived substitution, H401Y, in the ZIKV E protein via experimental evolution. The H401Y substitution significantly enhanced viral virulence and fitness in mammal cells and mice. Notably, the H401Y substitution has been detected in recent mosquito and human isolates from regions spanning Asia to the Americas. Our work elucidates unrecognized virulence determinant in the ZIKV genome that warrants urgent attention. Moreover, the findings underscore the critical need for extensive molecular surveillance and rigorous clinical observation to establish the potential impact in natural circulation. These endeavors are crucial for unraveling the potential of mutation to act as a catalyst for future epidemics, thereby preempting the public health challenges it may pose.

11.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36575831

RESUMO

Accurate variant pathogenicity predictions are important in genetic studies of human diseases. Inframe insertion and deletion variants (indels) alter protein sequence and length, but not as deleterious as frameshift indels. Inframe indel Interpretation is challenging due to limitations in the available number of known pathogenic variants for training. Existing prediction methods largely use manually encoded features including conservation, protein structure and function, and allele frequency to infer variant pathogenicity. Recent advances in deep learning modeling of protein sequences and structures provide an opportunity to improve the representation of salient features based on large numbers of protein sequences. We developed a new pathogenicity predictor for SHort Inframe iNsertion and dEletion (SHINE). SHINE uses pretrained protein language models to construct a latent representation of an indel and its protein context from protein sequences and multiple protein sequence alignments, and feeds the latent representation into supervised machine learning models for pathogenicity prediction. We curated training data from ClinVar and gnomAD, and created two test datasets from different sources. SHINE achieved better prediction performance than existing methods for both deletion and insertion variants in these two test datasets. Our work suggests that unsupervised protein language models can provide valuable information about proteins, and new methods based on these models can improve variant interpretation in genetic analyses.


Assuntos
Proteínas , Humanos , Virulência , Proteínas/genética , Sequência de Aminoácidos , Frequência do Gene
12.
Circulation ; 148(7): 589-606, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37203562

RESUMO

BACKGROUND: Aortic dissection (AD) is a fatal cardiovascular disorder without effective medications due to unclear pathogenic mechanisms. Bestrophin3 (Best3), the predominant isoform of bestrophin family in vessels, has emerged as critical for vascular pathological processes. However, the contribution of Best3 to vascular diseases remains elusive. METHODS: Smooth muscle cell-specific and endothelial cell-specific Best3 knockout mice (Best3SMKO and Best3ECKO, respectively) were engineered to investigate the role of Best3 in vascular pathophysiology. Functional studies, single-cell RNA sequencing, proteomics analysis, and coimmunoprecipitation coupled with mass spectrometry were performed to evaluate the function of Best3 in vessels. RESULTS: Best3 expression in aortas of human AD samples and mouse AD models was decreased. Best3SMKO but not Best3ECKO mice spontaneously developed AD with age, and the incidence reached 48% at 72 weeks of age. Reanalysis of single-cell transcriptome data revealed that reduction of fibromyocytes, a fibroblast-like smooth muscle cell cluster, was a typical feature of human ascending AD and aneurysm. Consistently, Best3 deficiency in smooth muscle cells decreased the number of fibromyocytes. Mechanistically, Best3 interacted with both MEKK2 and MEKK3, and this interaction inhibited phosphorylation of MEKK2 at serine153 and MEKK3 at serine61. Best3 deficiency induced phosphorylation-dependent inhibition of ubiquitination and protein turnover of MEKK2/3, thereby activating the downstream mitogen-activated protein kinase signaling cascade. Furthermore, restoration of Best3 or inhibition of MEKK2/3 prevented AD progression in angiotensin II-infused Best3SMKO and ApoE-/- mice. CONCLUSIONS: These findings unveil a critical role of Best3 in regulating smooth muscle cell phenotypic switch and aortic structural integrity through controlling MEKK2/3 degradation. Best3-MEKK2/3 signaling represents a novel therapeutic target for AD.


Assuntos
Dissecção Aórtica , Músculo Liso Vascular , Animais , Humanos , Camundongos , Dissecção Aórtica/genética , Sistema de Sinalização das MAP Quinases , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Fosforilação
13.
J Am Chem Soc ; 146(27): 18331-18340, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38900500

RESUMO

Efficient red-green-blue primary luminescence with an extraordinarily narrow band and durability is crucial for advanced display applications. Recently, the emergence of multiple-resonance (MR) from short-range atomic interactions has been shown to induce extremely narrow spectral widths in pure organic emitters. However, achieving wide-range color tuning without compromising color purity remains a persistent challenge for MR emitters. Herein, the concept of electronic donor/acceptor "core-shell" modulation is proposed within a boron/nitrogen (B/N) MR skeleton, enabling the rational utilization of intramolecular charge transfer to facilitate wavelength shift. The dense B atoms localized at the center of the molecule effectively compress the electron density and stabilize the lowest unoccupied molecular orbital wave function. This electron-withdrawing core is embedded with peripheral electron-donating atoms. Consequently, doping a single B atom into a deep-blue MR framework led to a profound bathochromic shift from 447 to 624 nm (∼0.8 eV) while maintaining a narrow spectral width of 0.10 eV in this pure-red emitter. Notably, organic light-emitting diodes assisted by thermally activated delayed fluorescence molecules achieved superb electroluminescent stability, with an LT99 (99% of the initial luminance) exceeding 400 h at an initial luminance of 1000 cd m-2, approaching commercial-level performance without the assistance of phosphors.

14.
Int J Cancer ; 154(6): 1111-1123, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37842828

RESUMO

Effective screening and early detection are critical to improve the prognosis of gastric cancer (GC). Our study aims to explore noninvasive multianalytical biomarkers and construct integrative models for preliminary risk assessment and GC detection. Whole genomewide methylation marker discovery was conducted with CpG tandems target amplification (CTTA) in cfDNA from large asymptomatic screening participants in a high-risk area of GC. The methylation and mutation candidates were validated simultaneously using one plasma from patients at various gastric lesion stages by multiplex profiling with Mutation Capsule Plus (MCP). Helicobacter pylori specific antibodies were detected with a recomLine assay. Integrated models were constructed and validated by the combination of multianalytical biomarkers. A total of 146 and 120 novel methylation markers were found in CpG islands and promoter regions across the genome with CTTA. The methylation markers together with the candidate mutations were validated with MCP and used to establish a 133-methylation-marker panel for risk assessment of suspicious precancerous lesions and GC cases and a 49-methylation-marker panel as well as a 144-amplicon-mutation panel for GC detection. An integrated model comprising both methylation and specific antibody panels performed better for risk assessment than a traditional model (AUC, 0.83 and 0.63, P < .001). A second model for GC detection integrating methylation and mutation panels also outperformed the traditional model (AUC, 0.82 and 0.68, P = .005). Our study established methylation, mutation and H. pylori-specific antibody panels and constructed two integrated models for risk assessment and GC screening. Our findings provide new insights for a more precise GC screening strategy in the future.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Metilação de DNA , Detecção Precoce de Câncer , Biomarcadores , Medição de Risco , Helicobacter pylori/genética , Biomarcadores Tumorais/genética , Ilhas de CpG , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia
15.
BMC Plant Biol ; 24(1): 167, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438916

RESUMO

BACKGROUND: Generating elite rice varieties with high yield and superior quality is the main goal of rice breeding programs. Key agronomic traits, including grain size and seed germination characteristics, affect the final yield and quality of rice. The RGA1 gene, which encodes the α-subunit of rice G-protein, plays an important role in regulating rice architecture, seed size and abiotic stress responses. However, whether RGA1 is involved in the regulation of rice quality and seed germination traits is still unclear. RESULTS: In this study, a rice mutant small and round grain 5 (srg5), was identified in an EMS-induced rice mutant library. Systematic analysis of its major agronomic traits revealed that the srg5 mutant exhibited a semi-dwarf plant height with small and round grain and reduced panicle length. Analysis of the physicochemical properties of rice showed that the difference in rice eating and cooking quality (ECQ) between the srg5 mutant and its wild-type control was small, but the appearance quality was significantly improved. Interestingly, a significant suppression of rice seed germination and shoot growth was observed in the srg5 mutant, which was mainly related to the regulation of ABA metabolism. RGA1 was identified as the candidate gene for the srg5 mutant by BSA analysis. A SNP at the splice site of the first intron disrupted the normal splicing of the RGA1 transcript precursor, resulting in a premature stop codon. Additional linkage analysis confirmed that the target gene causing the srg5 mutant phenotype was RGA1. Finally, the introduction of the RGA1 mutant allele into two indica rice varieties also resulted in small and round rice grains with less chalkiness. CONCLUSIONS: These results indicate that RGA1 is not only involved in the control of rice architecture and grain size, but also in the regulation of rice quality and seed germination. This study sheds new light on the biological functions of RGA1, thereby providing valuable information for future systematic analysis of the G-protein pathway and its potential application in rice breeding programs.


Assuntos
Oryza , Oryza/genética , Sementes/genética , Germinação/genética , Melhoramento Vegetal , Grão Comestível/genética , Proteínas de Ligação ao GTP
16.
Small ; 20(32): e2312098, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38461523

RESUMO

Double-borylated multiple-resonance (MR) skeletons are promising templates for high performance, while the chemical design space is relatively limited. Peripheral segments are often used to decorate/fuse MR skeletons and modulate the photophysics but they can also cause unwanted spectral broadening. Herein, a narrowband MR emitter ICzDBA by fusing an MR-featured donor segment indolocarbazole into a double-borylated MR skeleton is developed. In ICzDBA, the nitrogen atom located away from the core benzene ring can also contribute to the generation of the overall MR-featured distribution through the long-range conjugation effect, along with the other boron/nitrogen atoms on the phenyl center. Thus, ICzDBA in toluene displays a narrowband emission peaking at 507 nm with a full width at half maximum of merely 20 nm (0.09 eV). Moreover, organic light-emitting diode devices using ICzDBA emitter exhibit ultrapure green emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.27, 0.70) and a high external quantum efficiency of 32.5%. These results manifest the importance of MR characters of peripheral decorations/fusions in preserving the narrowband features of MR skeletons, which provides a solution for further expanding MR structures with well-maintained narrowband characters.

17.
BMC Microbiol ; 24(1): 130, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643095

RESUMO

BACKGROUND: Mycobacteria bloodstream infections are common in immunocompromised people and usually have disastrous consequences. As the primary phagocytes in the bloodstream, monocytes and neutrophils play critical roles in the fight against bloodstream mycobacteria infections. In contrast to macrophages, the responses of monocytes infected with the mycobacteria have been less investigated. RESULTS: In this study, we first established a protocol for infection of non-adherent monocyte-like THP-1 cells (i.e. without the differentiation induced by phorbol 12-myristate 13-acetate (PMA) by bacillus Calmette-Guérin (BCG). Via the protocol, we were then capable of exploring the global transcriptomic profiles of non-adherent THP-1 cells infected with BCG, and found that NF-κB, MAPK and PI3K-Akt signaling pathways were enhanced, as well as some inflammatory chemokine/cytokine genes (e.g. CCL4, CXCL10, TNF and IL-1ß) were up-regulated. Surprisingly, the Akt-HIF-mTOR signaling pathway was also activated, which induces trained immunity. In this in vitro infection model, increased cytokine responses to lipopolysaccharides (LPS) restimulation, higher cell viability, and decreased Candida albicans loads were observed. CONCLUSIONS: We have first characterized the transcriptomic profiles of BCG-infected non-adherent THP-1 cells, and first developed a trained immunity in vitro model of the cells.


Assuntos
Monócitos , Mycobacterium bovis , Humanos , Vacina BCG , Imunidade Treinada , Proteínas Proto-Oncogênicas c-akt/genética , Células THP-1 , Fosfatidilinositol 3-Quinases , Citocinas
18.
Microb Pathog ; 195: 106877, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39173853

RESUMO

BACKGROUND: Candida albicans is an opportunistic pathogen commonly found in human mucous membranes. In light of the escalating challenge posed by antibiotic resistance of C. albicans strains worldwide, it is an urgently necessary to explore alternative therapeutic options. OBJECTIVE: This study aims to assess the efficacy of two Cinnamaldehyde derivatives, 2-Cl Cinnamaldehyde (2-Cl CA) and 4-Cl Cinnamaldehyde (4-Cl CA), against C. albicans through both in vitro experiments and in vivo murine models and to evaluate their potential as new drug candidates for treating C. albicans. METHODS AND RESULTS: The minimum inhibitory concentrations (MICs) of Cinnamaldehyde 2-Cl and 4-Cl benzene ring derivatives against C. albicans were 25 µg/mL. Time-killing experiments revealed that both Cinnamaldehyde derivatives exhibited fungicidal activity against C. albicans at concentrations of 5 MIC and 10 MIC. In the checkerboard experiment, 4-Cl CA did not show any antagonistic effect when combined with first-line antifungal drugs. Instead, it exhibited additive effects in combination with nystatin. Both 2-Cl and 4-Cl CA demonstrated inhibitory activity against C. albicans biofilm formation, especially at 8 MIC and 16 MIC concentrations. In C. albicans biofilm eradication experiments, although high drug concentrations of 2-Cl and 4-Cl CA were unable to eradicate the biofilm completely, they were still effective in killing C. albicans cells within the biofilm. Moreover, sub-inhibitory concentrations of 4-Cl CA (ranging from 5 to 20 µg/mL) significantly inhibited cell aggregation and hyphal formation. Furthermore, 4-Cl CA effectively inhibited intracellular C. albicans infection in macrophages. Lastly, the effectiveness of 4-Cl CA was evaluated in a mouse model of hematogenous disseminated candidiasis caused by C. albicans, which revealed that 4-Cl CA significantly reduced fungal burden and improved mouse survival compared to the untreated controls. CONCLUSION: The 4-Cl CA exhibited inhibitory effects against C. albicans through both in vivo and in vitro models, demonstrating its therapeutic potential as a promising new drug candidate for treating drug-resistant candidiasis albicans.


Assuntos
Acroleína , Antifúngicos , Biofilmes , Candida albicans , Candidíase , Modelos Animais de Doenças , Farmacorresistência Fúngica , Fluconazol , Testes de Sensibilidade Microbiana , Acroleína/análogos & derivados , Acroleína/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Animais , Biofilmes/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Camundongos , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Fluconazol/farmacologia , Feminino , Camundongos Endogâmicos BALB C
19.
BMC Cancer ; 24(1): 985, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123182

RESUMO

BACKGROUND: In China, both percutaneous microwave/radiofrequency ablation liver partition plus portal vein embolization (PALPP) and transarterial chemoembolization (TACE) plus portal vein embolization (PVE) have been utilized in planned hepatectomy. However, there is a lack of comparative studies on the effectiveness of these two techniques for cases with insufficient future liver remnant (FLR). METHODS: Patients were categorized into either the PALPP group or the TACE + PVE group. Clinical data, including FLR growth rate, complications, secondary resection rate, and overall survival rate, were compared and analyzed for both groups retrospectively. RESULTS: Between December 2014 and October 2021, a total of 29 patients underwent TACE + PVE (n = 12) and PALPP (n = 17). In the TACE + PVE group, 7 patients successfully underwent two-stage hepatectomy, while in the PALPP group, 13 patients underwent the procedure (two-stage resection rate: 58.3% vs. 76.5%, P = 0.42). There were no significant differences in postoperative complications of one-stage procedures (11.8% vs. 8.3%, P > 0.05) and second-stage resection complication (0% vs. 46.2%, P = 0.05) between the TACE + PVE and PALPP groups. However, the PALPP group demonstrated a shorter time to FLR volume growth for second-stage resection (18.5 days vs. 66 days, P = 0.001) and KGR (58.5 ml/week vs. 7.7 ml/week, P = 0.001). CONCLUSIONS: Compared with TACE + PVE, PALPP results in a more significant increase in FLR volume and a higher rate of two-stage resection without increasing postoperative complications.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Hepatectomia , Neoplasias Hepáticas , Micro-Ondas , Veia Porta , Ablação por Radiofrequência , Humanos , Hepatectomia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/cirurgia , Quimioembolização Terapêutica/métodos , Ablação por Radiofrequência/métodos , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/cirurgia , Idoso , Adulto , Fígado/cirurgia , Fígado/irrigação sanguínea , Embolização Terapêutica/métodos , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida , China/epidemiologia , Terapia Combinada
20.
J Biomed Sci ; 31(1): 60, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849802

RESUMO

BACKGROUND: Flavivirus is a challenge all over the world. The replication of flavivirus takes place within membranous replication compartments (RCs) derived from endoplasmic reticulum (ER). Flavivirus NS1 proteins have been proven essential for the formation of viral RCs by remodeling the ER. The glycosylation of flavivirus NS1 proteins is important for viral replication, yet the underlying mechanism remains unclear. METHODS: HeLa cells were used to visualize the ER remodeling effects induced by NS1 expression. ZIKV replicon luciferase assay was performed with BHK-21 cells. rZIKV was generated from BHK-21 cells and the plaque assay was done with Vero Cells. Liposome co-floating assay was performed with purified NS1 proteins from 293T cells. RESULTS: We found that the glycosylation of flavivirus NS1 contributes to its ER remodeling activity. Glycosylation deficiency of NS1, either through N-glycosylation sites mutations or tunicamycin treatment, compromises its ER remodeling activity and interferes with viral RCs formation. Disruption of NS1 glycosylation results in abnormal aggregation of NS1, rather than reducing its membrane-binding activity. Consequently, deficiency in NS1 glycosylation impairs virus replication. CONCLUSIONS: In summary, our results highlight the significance of NS1 glycosylation in flavivirus replication and elucidate the underlying mechanism. This provides a new strategy for combating flavivirus infections.


Assuntos
Proteínas não Estruturais Virais , Replicação Viral , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Glicosilação , Humanos , Animais , Compartimentos de Replicação Viral/metabolismo , Células HeLa , Chlorocebus aethiops , Flavivirus/fisiologia , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/virologia , Células Vero
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