RESUMEN
ADP-ribosylation of proteins can profoundly impact their function and serves as an effective mechanism by which bacterial toxins impair eukaryotic cell processes. Here, we report the discovery that bacteria also employ ADP-ribosylating toxins against each other during interspecies competition. We demonstrate that one such toxin from Serratia proteamaculans interrupts the division of competing cells by modifying the essential bacterial tubulin-like protein, FtsZ, adjacent to its protomer interface, blocking its capacity to polymerize. The structure of the toxin in complex with its immunity determinant revealed two distinct modes of inhibition: active site occlusion and enzymatic removal of ADP-ribose modifications. We show that each is sufficient to support toxin immunity; however, the latter additionally provides unprecedented broad protection against non-cognate ADP-ribosylating effectors. Our findings reveal how an interbacterial arms race has produced a unique solution for safeguarding the integrity of bacterial cell division machinery against inactivating post-translational modifications.
Asunto(s)
ADP Ribosa Transferasas/metabolismo , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Proteínas del Citoesqueleto/metabolismo , N-Glicosil Hidrolasas/metabolismo , ADP Ribosa Transferasas/química , ADP Ribosa Transferasas/genética , ADP-Ribosilación , Adenosina Difosfato/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/antagonistas & inhibidores , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Dominio Catalítico , Proteínas del Citoesqueleto/antagonistas & inhibidores , Escherichia coli/crecimiento & desarrollo , Escherichia coli/inmunología , Escherichia coli/metabolismo , Humanos , Mutagénesis Sitio-Dirigida , N-Glicosil Hidrolasas/química , N-Glicosil Hidrolasas/genética , Estructura Terciaria de Proteína , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Alineación de Secuencia , Serratia/metabolismo , Imagen de Lapso de TiempoRESUMEN
Natural proteins are composed of 20 proteinogenic amino acids and their post-translational modifications (PTMs). However, due to the lack of a suitable nanopore sensor that can simultaneously discriminate between all 20 amino acids and their PTMs, direct sequencing of protein with nanopores has not yet been realized. Here, we present an engineered hetero-octameric Mycobacterium smegmatis porin A (MspA) nanopore containing a sole Ni2+ modification. It enables full discrimination of all 20 proteinogenic amino acids and 4 representative modified amino acids, Nω,N'ω-dimethyl-arginine (Me-R), O-acetyl-threonine (Ac-T), N4-(ß-N-acetyl-D-glucosaminyl)-asparagine (GlcNAc-N) and O-phosphoserine (P-S). Assisted by machine learning, an accuracy of 98.6% was achieved. Amino acid supplement tablets and peptidase-digested amino acids from peptides were also analyzed using this strategy. This capacity for simultaneous discrimination of all 20 proteinogenic amino acids and their PTMs suggests the potential to achieve protein sequencing using this nanopore-based strategy.
Asunto(s)
Nanoporos , Aminoácidos/química , Proteínas/metabolismo , Porinas/química , Porinas/metabolismo , Péptidos/químicaRESUMEN
Proofreading (editing) of mischarged tRNAs by cytoplasmic aminoacyl-tRNA synthetases (aaRSs), whose impairment causes neurodegeneration and cardiac diseases, is of high significance for protein homeostasis. However, whether mitochondrial translation needs fidelity and the significance of editing by mitochondrial aaRSs have been unclear. Here, we show that mammalian cells critically depended on the editing of mitochondrial threonyl-tRNA synthetase (mtThrRS, encoded by Tars2), disruption of which accumulated Ser-tRNAThr and generated a large abundance of Thr-to-Ser misincorporated peptides in vivo. Such infidelity impaired mitochondrial translation and oxidative phosphorylation, causing oxidative stress and cell cycle arrest in the G0/G1 phase. Notably, reactive oxygen species (ROS) scavenging by N-acetylcysteine attenuated this abnormal cell proliferation. A mouse model of heart-specific defective mtThrRS editing was established. Increased ROS levels, blocked cardiomyocyte proliferation, contractile dysfunction, dilated cardiomyopathy, and cardiac fibrosis were observed. Our results elucidate that mitochondria critically require a high level of translational accuracy at Thr codons and highlight the cellular dysfunctions and imbalance in tissue homeostasis caused by mitochondrial mistranslation.
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Aminoacil-ARNt Sintetasas , Cardiomiopatías , Cardiopatías , Animales , Ratones , Especies Reactivas de Oxígeno , Puntos de Control del Ciclo Celular , Estrés Oxidativo , MamíferosRESUMEN
Thyroid hormones (THs) are a variety of iodine-containing hormones that demonstrate critical physiological impacts on cellular activities. The assessment of thyroid function and the diagnosis of thyroid disorders require accurate measurement of TH levels. However, largely due to their structural similarities, the simultaneous discrimination of different THs is challenging. Nanopores, single-molecule sensors with a high resolution, are suitable for this task. In this paper, a hetero-octameric Mycobacterium smegmatis porin A (MspA) nanopore containing a single nickel ion immobilized to the pore constriction has enabled simultaneous identification of five representative THs including l-thyroxine (T4), 3,3',5-triiodo-l-thyronine (T3), 3,3',5'-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2) and 3,3'-diiodo-l-thyronine (3,3'-T2). To automate event classification and avoid human bias, a machine learning algorithm was also developed, reporting an accuracy of 99.0%. This sensing strategy is also applied in the analysis of TH in a real human serum environment, suggesting its potential use in a clinical diagnosis.
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Nanoporos , Humanos , Níquel , Hormonas Tiroideas/análisis , Hormonas Tiroideas/química , Tiroxina , TironinasRESUMEN
Tumour immune microenvironment (TIME) plays an indispensable role in tumour progression, and tumour-associated macrophages (TAMs) are the most abundant immune cells in TIME. Non-apoptotic regulated cell death (RCD) can avoid the influence of tumour apoptosis resistance on anti-tumour immune response. Specifically, autophagy, ferroptosis, pyroptosis and necroptosis mediate the crosstalk between TAMs and tumour cells in TIME, thus reprogram TIME and affect the progress of tumour. In addition, although some achievements have been made in immune checkpoint inhibitors (ICIs), there is still defect that ICIs are only effective for some people because non-apoptotic RCD can bypass the apoptosis resistance of tumour. As a result, ICIs combined with targeting non-apoptotic RCD may be a promising solution. In this paper, the basic molecular mechanism of non-apoptotic RCD, the way in which non-apoptotic RCD mediates crosstalk between TAMs and tumour cells to reprogram TIME, and the latest research progress in targeting non-apoptotic RCD and ICIs are reviewed.
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Neoplasias , Muerte Celular Regulada , Microambiente Tumoral , Macrófagos Asociados a Tumores , Animales , Humanos , Apoptosis , Autofagia , Ferroptosis/inmunología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/terapia , Muerte Celular Regulada/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/patologíaRESUMEN
Ferroptosis is an iron-dependent cell death mechanism involving the accumulation of lipid peroxides. As a critical regulator, glutathione peroxidase 4 (GPX4) has been demonstrated to be downregulated in epilepsy. However, the mechanism of ferroptosis in epilepsy remains unclear. In this study, bioinformatics analysis, analysis of epilepsy patient blood samples and cell and mouse experiments revealed strong associations among epilepsy, ferroptosis, microRNA-211-5p and purinergic receptor P2X 7 (P2RX7). P2RX7 is a nonselective ligand-gated homotrimeric cation channel, and its activation mainly increases neuronal activity during epileptic seizures. In our study, the upregulation of P2RX7 in epilepsy was attributed to the downregulation of microRNA (miR)-211-5p. Furthermore, P2RX7 has been found to regulate GPX4/HO-1 by alleviating lipid peroxidation induced by suppression of the MAPK/ERK signaling pathway in murine models. The dynamic decrease in miR-211-5p expression induces hypersynchronization and both nonconvulsive and convulsive seizures, and forebrain miR-211-5p suppression exacerbates long-lasting pentylenetetrazole-induced seizures. Additionally, in this study, induction of miR-211-5p expression or genetic-silencing of P2RX7 significantly reduced the seizure score and duration in murine models through the abovementioned pathways. These results suggest that the miR-211-5p/P2RX7 axis is a novel target for suppressing both ferroptosis and epilepsy.
Asunto(s)
Epilepsia , Ferroptosis , MicroARNs , Humanos , Animales , Ratones , Epilepsia/genética , Estrés Oxidativo , Convulsiones , MicroARNs/genética , Receptores Purinérgicos P2X7/genéticaRESUMEN
All-solid-state lithium batteries (ASSLBs) are highly promising as next-generation energy storage devices owing to their potential for great safety and high energy density. This work demonstrates that composite solid polymer electrolyte with vertically-aligned card-house structure can simultaneously improve the high rate and long-term cycling performance of ASSLBs. The vertical alignment of laponite nanosheets creates fast and uniform Li+ ion transport channels at the nanosheets/polymer interphase, resulting in high ionic conductivity of 8.9 × 10-4 S cm-1 and Li+ transference number of 0.32 at 60 °C, as well as uniformly distributed solid electrolyte interphase. Such electrolyte is characterized by high mechanical strength, low flammability, excellent structural stability and stable ion transport channels. In addition, the ASSLB cell with the electrolyte and LiFePO4 cathode delivers a high discharge specific capacity of 124.8 mAh g-1, which accounts for 85.6% of its initial capacity after 500 cycles at 1C. The reasonable design through structural control strategy by interconnecting the vertically-aligned nanosheets open a way to fabricate high performance composite solid polymer electrolytes.
RESUMEN
Ribonucleic acid (RNA) is a pivotal nucleic acid that plays a crucial role in regulating many biological activities. Recently, one study utilized a machine learning algorithm to automatically classify RNA structural events generated by a Mycobacterium smegmatis porin A nanopore trap. Although it can achieve desirable classification results, compared with deep learning (DL) methods, this classic machine learning requires domain knowledge to manually extract features, which is sophisticated, labor-intensive and time-consuming. Meanwhile, the generated original RNA structural events are not strictly equal in length, which is incompatible with the input requirements of DL models. To alleviate this issue, we propose a sequence-to-sequence (S2S) module that transforms the unequal length sequence (UELS) to the equal length sequence. Furthermore, to automatically extract features from the RNA structural events, we propose a sequence-to-sequence neural network based on DL. In addition, we add an attention mechanism to capture vital information for classification, such as dwell time and blockage amplitude. Through quantitative and qualitative analysis, the experimental results have achieved about a 2% performance increase (accuracy) compared to the previous method. The proposed method can also be applied to other nanopore platforms, such as the famous Oxford nanopore. It is worth noting that the proposed method is not only aimed at pursuing state-of-the-art performance but also provides an overall idea to process nanopore data with UELS.
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Aprendizaje Profundo , Nanoporos , Peso Molecular , Extractos Vegetales , ARN/químicaRESUMEN
Metastasis remains a significant cause to cancer-related mortality, underscoring the critical need for early detection and analysis of circulating tumor cells (CTCs). This study presents a novel microfluidic chip designed to efficiently capture A549 lung cancer cells by combining dielectrophoresis (DEP) and aptamer-based binding, thereby enhancing capture efficiency and specificity. The microchip features interdigitated electrodes made of indium-tin-oxide that generate a nonuniform electric field to manipulate CTCs. Following three chip design, scenarios were investigated: (A) bare glass surface, (B) glass modified with gold nanoparticles (AuNPs) only, and (C) glass modified with both AuNPs and aptamers. Experimental results demonstrate that AuNPs significantly enhance capture efficiency under DEP, with scenarios (B) and (C) exhibiting similar performance. Notably, scenario (C) stands out as aptamer-functionalized surfaces resisting fluid shear forces, achieving CTCs retention even after electric field deactivation. Additionally, an innovative reverse pumping method mitigates inlet clogging, enhancing experimental efficiency. This research offers valuable insights into optimizing surface modifications and understanding key factors influencing cell capture, contributing to the development of efficient cell manipulation techniques with potential applications in cancer research and personalized treatment options.
Asunto(s)
Aptámeros de Nucleótidos , Separación Celular , Electroforesis , Oro , Neoplasias Pulmonares , Nanopartículas del Metal , Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes , Humanos , Aptámeros de Nucleótidos/química , Células Neoplásicas Circulantes/patología , Neoplasias Pulmonares/patología , Electroforesis/métodos , Electroforesis/instrumentación , Separación Celular/métodos , Separación Celular/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Células A549 , Oro/química , Nanopartículas del Metal/química , Diseño de Equipo , Propiedades de SuperficieRESUMEN
KEY MESSAGE: The durable stripe rust resistance gene Yr30 was fine-mapped to a 610-kb region in which five candidate genes were identified by expression analysis and sequence polymorphisms. The emergence of genetically diverse and more aggressive races of Puccinia striiformis f. sp. tritici (Pst) in the past twenty years has resulted in global stripe rust outbreaks and the rapid breakdown of resistance genes. Yr30 is an adult plant resistance (APR) gene with broad-spectrum effectiveness and its durability. Here, we fine-mapped the YR30 locus to a 0.52-cM interval using 1629 individuals derived from residual heterozygous F5:6 plants in a Yaco"S"/Mingxian169 recombinant inbred line population. This interval corresponded to a 610-kb region in the International Wheat Genome Sequencing Consortium (IWGSC) RefSeq version 2.1 on chromosome arm 3BS harboring 30 high-confidence genes. Five genes were identified as candidate genes based on functional annotation, expression analysis by RNA-seq and sequence polymorphisms between cultivars with and without Yr30 based on resequencing. Haplotype analysis of the target region identified six haplotypes (YR30_h1-YR30_h6) in a panel of 1215 wheat accessions based on the 660K feature genotyping array. Lines with YR30_h6 displayed more resistance to stripe rust than the other five haplotypes. Near-isogenic lines (NILs) with Yr30 showed a 32.94% higher grain yield than susceptible counterparts when grown in a stripe rust nursery, whereas there was no difference in grain yield under rust-free conditions. These results lay a foundation for map-based cloning Yr30.
Asunto(s)
Mapeo Cromosómico , Resistencia a la Enfermedad , Genes de Plantas , Haplotipos , Enfermedades de las Plantas , Puccinia , Triticum , Triticum/genética , Triticum/microbiología , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Mapeo Cromosómico/métodos , Puccinia/patogenicidad , Basidiomycota/patogenicidad , Polimorfismo de Nucleótido Simple , Cromosomas de las Plantas/genéticaRESUMEN
BACKGROUND AND AIMS: Data on the safety and effectiveness of tenofovir alafenamide (TAF) plus peginterferon-alpha (Peg-IFN-α) in children with chronic hepatitis B (CHB) are lacking. The current study aimed to present the characteristics of four pediatric CHB patients who obtained a functional cure by using TAF and Peg-IFN-α. METHODS: In this case series study initiated in May 2019, ten children who had no clinical symptoms or signs received response-guided (HBV DNA undetectable, hepatitis B e antigen [HBeAg] loss or seroconversion, and hepatitis B surface antigen [HBsAg] loss or seroconversion) and functional cure-targeted (HBsAg loss or seroconversion) TAF (25 mg/d, orally) plus Peg-IFN-α-2b (180 µg/1.73m2, subcutaneously, once weekly) in combination (9/10) or sequential (1/10) therapy. The safety and effectiveness of these treatments were monitored. RESULTS: As of April 2024, four out of ten children obtained a functional cure after a mean of 31.5 months of treatment, and the other six children are still undergoing treatment. These four cured children, aged 2, 4, 8, and 6 years, were all HBeAg-positive and had alanine aminotransferase levels of 80, 47, 114, and 40 U/L; HBV DNA levels of 71200000, 93000000, 8220, and 96700000 IU/mL; and HBsAg levels of 39442.8, 15431.2, 22, and 33013.1 IU/mL, respectively. During treatment, all the children (10/10) experienced mild or moderate adverse events, including flu-like symptoms, anorexia, fatigue, and cytopenia. Notably, growth retardation (8/10) was the most significant adverse event; and it occurred in three cured children (3/4) treated with combination therapy and was present to a low degree in the other cured child (1/4) treated with sequential therapy. Fortunately, all three cured children recovered to or exceeded the normal growth levels at 9 months posttreatment. CONCLUSIONS: TAF plus Peg-IFN-α-2b therapy is potentially safe and effective for pediatric CHB patients, which may provide important insights for future clinical practice and study designs targeting functional cures for children with CHB.
Asunto(s)
Antivirales , Quimioterapia Combinada , Hepatitis B Crónica , Interferón-alfa , Polietilenglicoles , Proteínas Recombinantes , Tenofovir , Humanos , Tenofovir/uso terapéutico , Tenofovir/administración & dosificación , Tenofovir/análogos & derivados , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Masculino , Femenino , Antivirales/uso terapéutico , Antivirales/efectos adversos , Antivirales/administración & dosificación , Niño , Proteínas Recombinantes/uso terapéutico , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Polietilenglicoles/uso terapéutico , Polietilenglicoles/efectos adversos , Polietilenglicoles/administración & dosificación , Interferón-alfa/uso terapéutico , Interferón-alfa/administración & dosificación , Interferón-alfa/efectos adversos , Preescolar , Resultado del Tratamiento , Interferón alfa-2/uso terapéutico , Interferón alfa-2/administración & dosificación , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/efectos de los fármacos , ADN Viral/sangre , Alanina/uso terapéutico , Alanina/análogos & derivadosRESUMEN
AIMS: The current management of patients with atrial fibrillation (AF) and concomitant heart failure (HF) remains a significant challenge. Catheter ablation (CA) has been shown to improve left ventricular ejection fraction (LVEF) in these patients, but which patients can benefit from CA is still poorly understood. The aim of our study was to determine the predictors of improved ejection fraction in patients with persistent atrial fibrillation (PeAF) complicated with HF undergoing CA. METHODS AND RESULTS: A total of 435 patients with persistent AF underwent an initial CA between January 2019 and March 2023 in our hospital. We investigated consecutive patients with left ventricular systolic dysfunction (LVEF < 50%) measured by transthoracic echocardiography (TTE) within one month before CA. According to the LVEF changes at 6 months, these patients were divided into an improved group (fulfilling the '2021 Universal Definition of HF' criteria for LVEF recovery) and a nonimproved group. Eighty patients were analyzed, and the improvement group consisted of 60 patients (75.0%). In the univariate analysis, left ventricular end-diastolic diameter (P = 0.005) and low voltage zones in the left atrium (P = 0.043) were associated with improvement of LVEF. A receiver operating characteristic analysis determined that the suitable cutoff value for left ventricular end-diastolic diameter (LVDd) was 59 mm (sensitivity: 85.0%, specificity: 55.0%, area under curve: 0.709). A multivariate analysis showed that LVDd (OR = 0.85; 95% CI: 0.76-0.95, P = 0.005) and low voltage zones (LVZs) (OR = 0.26; 95% CI: 0.07-0.96, P = 0.043) were significantly independently associated with the improvement of LVEF. Additionally, parameters were significantly improved regarding the left atrial diameter, LVDd and ventricular rate after radiofrequency catheter ablation (all p < 0.05). CONCLUSIONS: The improvement of left ventricular ejection fraction (LVEF) occurred in 75.0% of patients. Our study provides additional evidence that LVDd < 59 mm and no low voltage zones in the left atrium can be used to jointly predict the improvement of LVEF after atrial fibrillation ablation.
Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Fibrilación Atrial/complicaciones , Función Ventricular Izquierda , Volumen Sistólico , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/complicaciones , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/complicaciones , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Resultado del TratamientoRESUMEN
Fusarium head blight (FHB) is a devastating disease that occurs in warm and humid environments. The German wheat 'Centrum' has displayed moderate to high levels of FHB resistance in the field for many years. In this study, an F6:8 recombinant inbred line (RIL) population derived from cross 'Centrum' × 'Xinong 979' was evaluated for FHB response following point inoculation in five environments. The population and parents were genotyped using the GenoBaits Wheat 16 K Panel. Stable quantitative trait loci (QTL) associated with FHB resistance in 'Centrum' were mapped on chromosome arms 2DS and 5BS. The most effective QTL, located in 2DS, was identified as a new chromosome region represented by a 1.4 Mb interval containing 17 candidate genes. Another novel QTL was mapped in chromosome arm 5BS of a 5BS to 7BS translocation chromosome. In addition, two environmentally sensitive QTL were mapped on chromosome arms 2BL from 'Centrum' and 5AS from 'Xinong 979'. Polymorphisms of flanking phenotypic variance explained (PVE) markers (allele-specific quantitative PCR [AQP]) AQP-6 for QFhb.nwafu-2DS and 16K-13073 for QFhb.nwafu-5BS were validated in a panel of 217 cultivars and breeding lines. These markers could be useful for marker-assisted selection (MAS) of FHB resistance and provide a starting point for fine mapping and marker-based cloning of the resistance genes.
Asunto(s)
Mapeo Cromosómico , Cromosomas de las Plantas , Resistencia a la Enfermedad , Fusarium , Enfermedades de las Plantas , Sitios de Carácter Cuantitativo , Triticum , Sitios de Carácter Cuantitativo/genética , Triticum/genética , Triticum/microbiología , Fusarium/fisiología , Fusarium/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Resistencia a la Enfermedad/genética , Cromosomas de las Plantas/genética , Genotipo , Fenotipo , Marcadores Genéticos/genéticaRESUMEN
It is crucial to accurately and rapidly monitor the levodopa (LD) concentration for accurate classification and treatment of dyskinesia in Parkinson's disease. In this paper, 3D graphene foam (GF) with a highly conductive network is obtained by chemical vapor deposition. 3D GF serves as the substrate for hydrothermal in situ growth of tapered cross-linked ZnO nanowire bundle arrays (ZnO NWBAs), enabling the development of a highly sensitive detection platform for LD. The formation mechanism of a tapered cross-linked ZnO nanowire bundle arrays on 3D GF is put forward. The integration of 3D GF and ZnO NWBAs can accelerate the electron transfer rate and increase the contact area with biomolecules, resulting in high electrochemical properties. The electrode composed of ZnO NWBAs on 3D GF exhibits significant sensitivity (1.66 µA·µM-1·cm-2) for LD detection in the concentration range 0-60 µM. The electrode is able to rapidly and specifically determine LD in mixed AA or UA solution. The selectivity mechanism of the electrode is also explained by the bandgap model. Furthermore, the successful detection of LD in serum demonstrates the practicality of the electrode and its great potential for clinical application.
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Técnicas Electroquímicas , Grafito , Levodopa , Límite de Detección , Nanocables , Óxido de Zinc , Grafito/química , Óxido de Zinc/química , Nanocables/química , Levodopa/sangre , Levodopa/análisis , Levodopa/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Electrodos , HumanosRESUMEN
Nucleotide sugars, the glycosyl donors in the biosynthesis of carbohydrates, are critical ingredients in the growth and development of all living organisms. A variety of nucleotide sugars simultaneously exist in biological samples. They, however, have only minor structural differences, which make them extremely difficult to discriminate. In this work, a phenylboronic acid (PBA)-modified Mycobacterium smegmatis porin A (MspA) hetero-octamer was applied to sense nucleotide sugars. Five representative nucleotide sugars, including guanosine diphosphate mannose (GDP-Man), adenosine diphosphate glucose (ADP-Glc), uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), uridine diphosphate glucose (UDP-Glc), and uridine diphosphate glucoronic acid (UDP-GlcA), were successfully distinguished. A custom machine learning algorithm was also employed to automatically identify events, reporting a general accuracy of 99.4%. This sensing strategy provides a rapid, direct, and accurate method for identifying different nucleotide sugars. However, single-molecule identification of nucleotide sugars has never been previously reported, to the best of our knowledge.
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Nanoporos , Azúcares de Uridina Difosfato , Humanos , Nucleótidos , Azúcares , Uridina Difosfato N-AcetilglucosaminaRESUMEN
Nucleoside drugs, which are analogues of natural nucleosides, have been widely applied in the clinical treatment of viral infections and cancers. The development of nucleoside drugs, repurposing of existing drugs, and combined use of multiple drug types have made the rapid sensing of nucleoside drugs urgently needed. Nanopores are emerging single-molecule sensors that have high resolution to resolve even minor structural differences between chemical compounds. Here, an engineered Mycobacterium smegmatis porin A hetero-octamer was used to perform general nucleoside drug analysis. Ten nucleoside drugs were simultaneously detected and fully discriminated. An accuracy of >99.9% was consequently reported. This sensing capacity was further demonstrated in direct nanopore analysis of ribavirin buccal tablets, confirming its sensing reliability against complex samples and environments. No sample separation is needed, however, significantly minimizing the complexity of the measurement. This technique may inspire nanopore applications in pharmaceutical production and pharmacokinetics measurements.
Asunto(s)
Nanoporos , Nucleósidos , Reproducibilidad de los Resultados , Porinas/química , Mycobacterium smegmatis/químicaRESUMEN
Hypopharyngeal squamous cell carcinoma (HSCC) is a kind of malignant tumor with a poor prognosis and low quality of life in the otolaryngology department. It has been found that microRNA (miRNA) plays an important role in the occurrence and development of various tumors. This study found that the expression level of miRNA-107 (miR-107) in HSCC was significantly reduced. Subsequently, we screened out the downstream direct target gene Neuronal Vesicle Trafficking Associated 1 (NSG1) related to miR-107 through bioinformatics analysis and found that the expression of NSG1 was increased in HSCC tissues. Following the overexpression of miR-107 in HSCC cells, it was observed that miR-107 directly suppressed NSG1 expression, leading to increased apoptosis, decreased proliferation, and reduced invasion capabilities of HSCC cells. Subsequent experiments involving the overexpression and knockdown of NSG1 in HSCC cells demonstrated that elevated NSG1 levels enhanced cell proliferation, migration, and invasion, while the opposite effect was observed upon NSG1 knockdown. Further investigations revealed that changes in NSG1 levels in the HSCC cells were accompanied by alterations in ERK signaling pathway proteins, suggesting a potential regulatory role of NSG1 in HSCC cell proliferation, migration, and invasion through the ERK pathway. These findings highlight the significance of miR-107 and NSG1 in hypopharyngeal cancer metastasis, offering promising targets for therapeutic interventions and prognostic evaluations for HSCC.
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Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hipofaríngeas , Sistema de Señalización de MAP Quinasas , MicroARNs , Humanos , Masculino , Apoptosis/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Progresión de la Enfermedad , Neoplasias Hipofaríngeas/genética , Neoplasias Hipofaríngeas/patología , Neoplasias Hipofaríngeas/metabolismo , Sistema de Señalización de MAP Quinasas/genética , MicroARNs/genética , MicroARNs/metabolismo , Invasividad Neoplásica , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismoRESUMEN
Disaccharides are composed of two monosaccharide subunits joined by a glycosidic linkage in an α or ß configuration. Different combinations of isomeric monosaccharide subunits and different glycosidic linkages result in different isomeric disaccharide products. Thus, direct discrimination of these disaccharide isomers from a mixture is extremely difficult. In this paper, a hetero-octameric Mycobacterium smegmatis porinâ A (MspA) nanopore conjugated with a phenylboronic acid (PBA) adapter was applied for disaccharide sensing, with which three most widely known disaccharides in nature, including sucrose, lactose and maltose, were clearly discriminated. Besides, all six isomeric α-D-glucopyranosyl-D-fructoses, differing only in their glycosidic linkages, were also well resolved. Assisted by a custom machine learning algorithm, a 0.99 discrimination accuracy is achieved. Nanopore discrimination of disaccharide isomers with different glycosidic linkages, which has never been previously demonstrated, is inspiring for nanopore saccharide sequencing. This sensing capacity was also applied in direct identification of isomaltulose additives in a commercial sucrose-free yogurt, from which isomaltulose, lactose and L-lactic acid were simultaneously detected.
Asunto(s)
Disacáridos , Nanoporos , Glicósidos , Mycobacterium smegmatis , Lactosa , Porinas , MonosacáridosRESUMEN
BACKGROUND: PARP inhibitor (PARPi), as a kind of DNA damage repair inhibitor, has been shown to be effective in various solid tumors and hematologic malignancies. Natural killer/T cell lymphoma (NKTCL) is a highly aggressive malignancy, the treatment of which has long been a major challenge in the clinic. Here, we investigated the efficacy and mechanism of PARPi, and the therapeutic value of PARPi combined with cisplatin in NKTCL. METHODS: The cell proliferation, cell apoptosis, and cell cycle of NKTCL cells were detected respectively by CCK-8 and flow cytometry. The changes of mRNA expression and protein level were measured respectively by mRNA-sequencing, quantitative real-time PCR, western blotting, and immunofluorescence. LMO2 expression was detected by immunohistochemistry and western blotting. Targeted knockdown of LMO2 was conducted by short hairpin RNA. The tumor xenograft models were established to evaluate the efficacy of drugs in vivo. RESULTS: PARPi inhibited cell proliferation, promoted cell apoptosis, and induced S-phase cell cycle arrest in NKTCL cells. PARPi led to the accumulation of DNA damage by blocking DNA repair and DNA replication. Additionally, LMO2 deficiency reduced the sensitivity of NKTCL cells to PARPi. Finally, the combination of PARPi and cisplatin exhibited significant synergistic effects both in vitro and in vivo. CONCLUSIONS: In summary, we found that PARPi exerted an anti-tumor effect via LMO2 and synergized with cisplatin in NKTCL, which provides the theoretical basis for the clinical application of PARPi.
Asunto(s)
Antineoplásicos , Linfoma de Células T , Linfoma , Humanos , Cisplatino/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Línea Celular Tumoral , Antineoplásicos/farmacología , Células Asesinas Naturales , ARN Mensajero , Proteínas Proto-Oncogénicas/farmacología , Proteínas Adaptadoras Transductoras de Señales/farmacología , Proteínas con Dominio LIM/farmacologíaRESUMEN
MOTIVATION: As a rising research topic, brain imaging genetics aims to investigate the potential genetic architecture of both brain structure and function. It should be noted that in the brain, not all variations are deservedly caused by genetic effect, and it is generally unknown which imaging phenotypes are promising for genetic analysis. RESULTS: In this work, genetic variants (i.e. the single nucleotide polymorphism, SNP) can be correlated with brain networks (i.e. quantitative trait, QT), so that the connectome (including the brain regions and connectivity features) of functional brain networks from the functional magnetic resonance imaging data is identified. Specifically, a connection matrix is firstly constructed, whose upper triangle elements are selected to be connectivity features. Then, the PageRank algorithm is exploited for estimating the importance of different brain regions as the brain region features. Finally, a deep self-reconstruction sparse canonical correlation analysis (DS-SCCA) method is developed for the identification of genetic associations with functional connectivity phenotypic markers. This approach is a regularized, deep extension, scalable multi-SNP-multi-QT method, which is well-suited for applying imaging genetic association analysis to the Alzheimer's Disease Neuroimaging Initiative datasets. It is further optimized by adopting a parametric approach, augmented Lagrange and stochastic gradient descent. Extensive experiments are provided to validate that the DS-SCCA approach realizes strong associations and discovers functional connectivity and brain region phenotypic biomarkers to guide disease interpretation. AVAILABILITY AND IMPLEMENTATION: The Matlab code is available at https://github.com/meimeiling/DS-SCCA/tree/main. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.