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1.
Microbiome ; 12(1): 169, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39252132

RESUMO

BACKGROUND: Plants have evolved various defense mechanisms against insect herbivores, including the formation of physical barriers, the synthesis of toxic metabolites, and the activation of phytohormone responses. Although plant-associated microbiota influence plant growth and health, whether they play a role in plant defense against insect pests in natural ecosystems is unknown. RESULTS: Here, we show that leaves of beetle-damaged weeping willow (Salix babylonica) trees are more resistant to the leaf beetle Plagiodera versicolora (Coleoptera) than those of undamaged leaves. Bacterial community transplantation experiments demonstrated that plant-associated microbiota from the beetle-damaged willow contribute to the resistance of the beetle-damaged willow to P. versicolora. Analysis of the composition and abundance of the microbiome revealed that Pseudomonas spp. is significantly enriched in the phyllosphere, roots, and rhizosphere soil of beetle-damaged willows relative to undamaged willows. From a total of 49 Pseudomonas strains isolated from willows and rhizosphere soil, we identified seven novel Pseudomonas strains that are toxic to P. versicolora. Moreover, re-inoculation of a synthetic microbial community (SynCom) with these Pseudomonas strains enhances willow resistance to P. versicolora. CONCLUSIONS: Collectively, our data reveal that willows can exploit specific entomopathogenic bacteria to enhance defense against P. versicolora, suggesting that there is a complex interplay among plants, insects, and plant-associated microbiota in natural ecosystems.


Assuntos
Besouros , Folhas de Planta , Pseudomonas , Salix , Animais , Salix/microbiologia , Besouros/microbiologia , Folhas de Planta/microbiologia , Microbiota , Rizosfera , Microbiologia do Solo , Herbivoria , Raízes de Plantas/microbiologia , Doenças das Plantas/microbiologia
2.
Mol Plant ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39148293

RESUMO

Root-knot nematodes (RKNs) are plant pests that infect the roots of host plants. Bacillus thuringiensis (Bt) nematicidal proteins exhibited toxicity to nematodes. However, the application of nematicidal proteins for plant protection is hampered by the lack of effective delivery systems in transgenic plants. In this study, we discovered the accumulation of leucoplasts (root plastids) in galls and RKN-induced giant cells. RKN infection causes the degradation of leucoplasts into small vesicle-like structures, which are responsible for delivering proteins to RKNs, as observed through confocal microscopy and immunoelectron microscopy. We showed that different-sized proteins from leucoplasts could be taken up by Meloidogyne incognita female. To further explore the potential applications of leucoplasts, we introduced the Bt crystal protein Cry5Ba2 into tobacco and tomato leucoplasts by fusing it with a transit peptide. The transgenic plants showed significant resistance to RKNs. Intriguingly, RKN females preferentially took up Cry5Ba2 protein when delivered through plastids rather than the cytosol. The decrease in progeny was positively correlated with the delivery efficiency of the nematicidal protein. In conclusion, this study offers new insights into the feeding behavior of RKNs and their ability to ingest leucoplast proteins, and demonstrates that root leucoplasts can be used for delivering nematicidal proteins, thereby offering a promising approach for nematode control.

3.
Transl Cancer Res ; 13(7): 3589-3598, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39145074

RESUMO

Background: Circulating tumor cells (CTCs) has shown important prognostic value in non-small cell lung cancer (NSCLC). However, the present low sensitivity of CTC capture technology restricts their clinical application. This study aims to explore the feasibility of combining the peripheral blood cell (PBC)-derived inflammation-based score with CTCs to increase the prognostic value of CTCs in NSCLC. Methods: Sixty volunteers diagnosed with NSCLC were recruited. CTC count and six inflammation-based scores were examined and the association with progression-free survival (PFS) and overall survival (OS) was explored. The changes in the CTC counts before and after the immunotherapy were observed. Results: Multivariate analysis showed that CTCs >7 [hazard ratio (HR) =9.07; 95% confidence interval (CI): 3.68-22.37, P<0.001] and monocytes-to-lymphocytes ratio (MLR) > 0.2 (HR =3.07; 95% CI: 1.21-7.84; P=0.01) were associated with shorter OS and PFS in patients with NSCLC. Patients with CTCs >7 and MLR >0.2 had 12.30 times increased risk of death (P<0.001) and 6.10 times increased risk of disease progression (P=0.002) compared with those with CTCs ≤7 and MLR ≤0.2. Decreased CTC counts after immunotherapy were closely related to disease control (r=0.535, P=0.01). Conclusions: CTCs and MLR are both independent risk factors for prognosis in patients with NSCLC. The combination of CTCs with MLR significantly increased the prognostic value of CTCs, which would contribute to stratification of NSCLC patients and providing precise treatment. Dynamic monitoring of CTCs efficiently shows the immunotherapy response in NSCLC.

4.
Mol Omics ; 20(7): 469-482, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38982979

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a chronic hepatic disease. The incidence and prevalence of NAFLD have increased greatly in recent years, and there is still a lack of effective drugs. Autophagy plays an important role in promoting liver metabolism and maintaining liver homeostasis, and defects in autophagy levels are considered to be related to the development of NAFLD. However, the molecular mechanisms of autophagy in NAFLD still remain unknown. In this study, we identified 6 autophagy-associated hub genes using gene expression profiles obtained from the GSE48452 and GSE89632 datasets. Biomarkers were screened according to gene significance (GS) and module membership (MM) using weighted gene co-expression network analysis (WGCNA), and the immune infiltration landscape of the liver in NAFLD patients was explored using the CIBERSORT algorithm. Subsequently, we analyzed the relationship between liver non-parenchymal cells and autophagy-related hub genes using scRNA-seq data (GSE129516). Finally, we separated the NAFLD patients into two groups based on 6 hub genes by consensus clustering and screened 10 potential autophagy-related small molecules based on the cMAP database.


Assuntos
Autofagia , Redes Reguladoras de Genes , Fígado , Hepatopatia Gordurosa não Alcoólica , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Humanos , Autofagia/genética , Fígado/metabolismo , Fígado/patologia , Perfilação da Expressão Gênica , Transcriptoma/genética , Biomarcadores , Biologia Computacional/métodos , Bases de Dados Genéticas
5.
Stem Cell Res ; 77: 103433, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718593

RESUMO

An induced pluripotent stem cell (iPSC) line (SDUCHi001-A) was established using peripheral blood mononuclear cells (PBMCs) from a healthy 6 years old boy. Reprogramming of the PBMCs was achieved through non-integrating delivery of OCT4, SOX2, KFL4, BCL-XL, and c-MYC. The iPSC line expressed pluripotency markers, had a normal karyotype and trilineage differentiation potential.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Humanos , Masculino , Criança , Diferenciação Celular , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/citologia , Linhagem Celular , Reprogramação Celular , Cariótipo
6.
Materials (Basel) ; 17(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612070

RESUMO

MAX phases have great research value and application prospects, but it is challenging to synthesize the MAX phases containing Cd and Sb for the time being. In this paper, we confirmed the existence of the 312 MAX phases of Zr3CdC2 and Zr3SbC2, both from theoretical calculations and experimental synthesis. The Zr3AC2 (A = Cd, Sb) phase was predicted by the first-principles calculations, and the two MAX phases were confirmed to meet the requests of thermal, thermodynamic, and mechanical stabilities using formation energy, phonon dispersion, and the Born-Huang criteria. Their theoretical mechanical properties were also systematically investigated. It was found that the elastic moduli of Zr3CdC2 and Zr3SbC2 were 162.8 GPa and 164.3 GPa, respectively. Then, differences in the mechanical properties of Zr3AC2 (A = Cd, In, Sn, and Sb) were explained using bond layouts and charge transfers. The low theoretical Vickers hardness of the Zr3CdC2 (5.4 GPa) and Zr3SbC2 (4.3 GPa) phases exhibited excellent machinability. Subsequently, through spark plasma sintering, composites containing Zr3CdC2 and Zr3SbC2 phases were successfully synthesized at the temperatures of 850 °C and 1300 °C, respectively. The optimal molar ratio of Zr:Cd/Sb:C was determined as 3:1.5:1.5. SEM and the EDS results analysis confirmed the typical layered microstructure of Zr3CdC2 and Zr3SbC2 grains.

7.
Pest Manag Sci ; 80(7): 3098-3106, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38319036

RESUMO

BACKGROUND: Bacillus thuringiensis (Bt) and its crystal toxin or δ-endotoxins (Cry) offer great potential for the efficient control of crop pests. A vast number of pests can potentially infect the same host plant, either simultaneously or sequentially. However, no effective Bt-Cry protein has been reported to control both aphids and plant parasitic nematodes due to its highly specific activity. RESULTS: Our study indicated that the Cry5Ba2 protein was toxic to the green peach aphid Myzus persicae, which had a median lethal concentration (LC50) of 9.7 ng µL-1 and fiducial limits of 3.1-34.6 ng µL-1. Immunohistochemical localization of Cry5Ba2 revealed that it could bind to the apical tip of microvilli in midgut regions. Moreover, transgenic tobacco plants expressing Cry5Ba2 exhibited significant resistance to Myzus persicae, as evidenced by reduced insect survival and impaired fecundity, and also intoxicated the Meloidogyne incognita as indicated by a decrease in galls and progeny reproduction. CONCLUSION: In sum, we identified a new aphicidal Bt toxin resource that could simultaneously control both aboveground and belowground pests, thus extending the application range of Bt-based strategy for crop protection. © 2024 Society of Chemical Industry.


Assuntos
Afídeos , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias , Endotoxinas , Proteínas Hemolisinas , Nicotiana , Plantas Geneticamente Modificadas , Tylenchoidea , Animais , Nicotiana/genética , Nicotiana/parasitologia , Endotoxinas/genética , Endotoxinas/metabolismo , Afídeos/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Plantas Geneticamente Modificadas/genética , Tylenchoidea/fisiologia , Tylenchoidea/efeitos dos fármacos , Controle Biológico de Vetores , Doenças das Plantas/parasitologia
8.
Heliyon ; 10(3): e25229, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38333787

RESUMO

High-altitude areas are characterized by low pressure and hypoxia, which have a significant impact on various body systems. This study aimed to investigate the alterations in cardiac index and right ventricular hypertrophy index(RVHI) in rats at different altitudes.Twenty-one male Sprague-Dawley (SD) rats aged 4 weeks were randomly divided into three groups based on altitude. The rats were raised for 28 weeks and then transferred to Qinghai University Plateau Medicine Laboratory. Body weight was measured, heart organs were isolated and weighed, and cardiac index and right ventricular hypertrophy index were determined. Statistical analysis was performed on the data from the three groups. Compared with the plain group, the body weight of the middle-altitude group was significantly decreased (P < 0.05), and cardiac index, RVHI-1, RVHI-2 increased significantly ((P < 0.05). The body weight, whole heart mass, right ventricular mass were significantly decreased in high-altitude group (P < 0.05), RVHI-1 and RVHI-2 were significantly increased (P < 0.05). Compared with the middle-altitude group, the body weight, whole heart mass and right ventricular mass of the high-altitude group were significantly decreased (P < 0.05), and RVHI-1 and RVHI-2 were significantly increased (P < 0.05). Increasing altitude led to a decrease in body weight, whole heart mass, and right ventricular mass in rats, indicating structural changes in the right heart. Additionally, the proportion of right heart to body weight and whole heart increased with altitude.

9.
Nat Struct Mol Biol ; 31(1): 42-53, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177668

RESUMO

DNA cytosine methylation plays a vital role in repressing retrotransposons, and such derepression is linked with developmental failure, tumorigenesis and aging. DNA methylation patterns are formed by precisely regulated actions of DNA methylation writers (DNA methyltransferases) and erasers (TET, ten-eleven translocation dioxygenases). However, the mechanisms underlying target-specific oxidation of 5mC by TET dioxygenases remain largely unexplored. Here we show that a large low-complexity domain (LCD), located in the catalytic part of Tet enzymes, negatively regulates the dioxygenase activity. Recombinant Tet3 lacking LCD is shown to be hyperactive in converting 5mC into oxidized species in vitro. Endogenous expression of the hyperactive Tet3 mutant in mouse oocytes results in genome-wide 5mC oxidation. Notably, the occurrence of aberrant 5mC oxidation correlates with a consequent loss of the repressive histone mark H3K9me3 at ERVK retrotransposons. The erosion of both 5mC and H3K9me3 causes ERVK derepression along with upregulation of their neighboring genes, potentially leading to the impairment of oocyte development. These findings suggest that Tet dioxygenases use an intrinsic auto-regulatory mechanism to tightly regulate their enzymatic activity, thus achieving spatiotemporal specificity of methylome reprogramming, and highlight the importance of methylome integrity for development.


Assuntos
5-Metilcitosina , Dioxigenases , Animais , Camundongos , 5-Metilcitosina/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Retroelementos/genética , Metilação de DNA , Oócitos/metabolismo , Desmetilação
10.
J Econ Entomol ; 117(1): 82-92, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38146627

RESUMO

Pseudomonas fluorescens group, such as Pseudomonas protegens and Pseudomonas chlororaphis, can be utilized as insect-killing agents. Most insecticidal Pseudomonas described so far have high toxicity for insects of the order Lepidoptera. In this study, Pseudomonas strain PcR3-3 was isolated from the willow root. It showed a high mortality for the coleopteran species Plagiodera versicolora (Coleoptera: Chrysomelidae), but not for the lepidopteran Helicoverpa armigera. Strain PcR3-3 displayed high colonization ability in the P. versicolora compared with P. chlororaphis PCL1391, indicating that the insecticidal activities correlated with the colonization ability of Pseudomonas strain in the host. Phylogenetic analysis of the genome revealed that PcR3-3 belonged to P. chlororaphis subsp. aureofaciens. Numerous insecticidal protein-encoding genes, typical biosynthetic gene clusters for some insecticidal metabolite and type VI secretion system, known to be involved in insect pathogenicity, were present in the P. chlororaphis PcR3-3 genome. However, the insecticidal toxin Fit-encoding gene which commonly presents in P. chlororaphis, was not found in the P. chlororaphis PcR3-3 genome. Furthermore, there are some divergent insecticidal genes between P. chlororaphis PcR3-3 and P. chlororaphis PCL1391. This finding implies that P. chlororaphis PcR3-3 is a promising biocontrol agent for pest management applications. The P. chlororaphis-P. versicolora association can be used as a model system to study the interaction between Pseudomonas and coleopteran insects.


Assuntos
Besouros , Inseticidas , Pseudomonas chlororaphis , Animais , Pseudomonas chlororaphis/genética , Inseticidas/farmacologia , Filogenia , Genômica , Insetos
11.
Biomaterials ; 305: 122455, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38160626

RESUMO

The therapeutic efficacy of cuproptosis combined with phototheranostics is still hindered by easy copper efflux, nonspecific accumulation and limited light penetration depth. Here, a high-performance NIR-II semiconductor polymer was first synthesized through dual-donor engineering. Then a biomimetic cuproptosis amplifier (PCD@CM) was prepared by Cu(II)-mediated coordinative self-assembly of NIR-II ultrasmall polymer dots and the chemotherapeutic drug DOX, followed by camouflaging of tumor cell membranes. After homologous targeting delivery to tumor cells, overexpressed GSH in the tumor microenvironment (TME) triggers the disassembly of the amplifier and the release of therapeutic components through the reduction of Cu(II) to Cu(I), which enable NIR-II fluorescence/photoacoustic imaging-guided NIR-II photothermal therapy (PTT) and chemotherapy. The released Cu(I) induces the aggregation of lipoylated mitochondrial proteins accompanied by the loss of iron-sulfur proteins, leading to severe proteotoxic stress and eventually cuproptosis. NIR-II PTT and GSH depletion render tumor cells more sensitive to cuproptosis. The amplified cuproptosis sensitization provokes significant immune surveillance, triggering the immunogenic cell death (ICD) to promote cytotoxic T lymphocyte infiltration together with aPD-L1-mediated immune checkpoint blockade. This work proposes a new strategy to develop cuproptosis sensitization systems enhanced by NIR-II phototheranostics with homologous targeting and anti-tumor immune response capabilities.


Assuntos
Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Humanos , Fototerapia , Cobre/uso terapêutico , Biomimética , Polímeros/uso terapêutico , Neoplasias/terapia , Imunoterapia , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral , Microambiente Tumoral
12.
Sensors (Basel) ; 23(23)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38067956

RESUMO

The total viable count (TVC) of bacteria is an important index to evaluate the freshness and safety of dishes. To improve the accuracy and robustness of spectroscopic detection of total viable bacteria count in a complex system, a new method based on a near-infrared (NIR) hyperspectral hybrid model and Support Vector Machine (SVM) algorithms was developed to directly determine the total viable count in intact beef dish samples in this study. Diffuse reflectance data of intact and crushed samples were tested by NIR hyperspectral and processed using Multiplicative Scattering Correction (MSC) and Competitive Adaptive Reweighted Sampling (CARS). Kennard-Stone (KS) and Samples Set Partitioning Based on Joint X-Y Distance (SPXY) algorithms were used to select the optimal number of standard samples transferred by the model combined with root mean square error. The crushed samples were transferred into the complete samples prediction model through the Direct Standardization (DS) algorithm. The spectral hybrid model of crushed samples and full samples was established. The results showed that the Determination Coefficient of Calibration (RP2) value of the total samples prediction set increased from 0.5088 to 0.8068, and the value of the Root Mean Square Error of Prediction (RMSEP) decreased from 0.2454 to 0.1691 log10 CFU/g. After establishing the hybrid model, the RMSEP value decreased by 9.23% more than before, and the values of Relative Percent Deviation (RPD) and Reaction Error Relation (RER) increased by 12.12% and 10.09, respectively. The results of this study showed that TVC instewed beef samples can be non-destructively determined based on the DS model transfer method combined with the hybrid model strategy. This study provided a reference for solving the problem of poor accuracy and reliability of prediction models in heterogeneous samples.


Assuntos
Algoritmos , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Bovinos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Reprodutibilidade dos Testes , Análise dos Mínimos Quadrados , Máquina de Vetores de Suporte
13.
BMJ Open ; 13(12): e074309, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38154879

RESUMO

BACKGROUND: Recently, with the rapid development of the perinatal medical system and related life-saving techniques, both the short-term and long-term prognoses of extremely preterm infants (EPIs) have improved significantly. In rapidly industrialising countries like China, the survival rates of EPIs have notably increased due to the swift socioeconomic development. However, there is still a reasonably lower positive response towards the treatment of EPIs than we expected, and the current situation of withdrawing care is an urgent task for perinatal medical practitioners. OBJECTIVE: To develop and validate a model that is practicable for EPIs as soon as possible after birth by regression analysis, to assess the risk of mortality and chance of survival. METHODS: This multicentre prospective cohort study used datasets from the Sino-Northern Neonatal Network, including 46 neonatal intensive care units (NICUs). Risk factors including maternal and neonatal variables were collected within 1 hour post-childbirth. The training set consisted of data from 41 NICUs located within the Shandong Province of China, while the validation set included data from 5 NICUs outside Shandong Province. A total of 1363 neonates were included in the study. RESULTS: Gestational age, birth weight, pH and lactic acid in blood gas analysis within the first hour of birth, moderate-to-severe hypothermia on admission and adequate antenatal corticosteroids were influencing factors for EPIs' mortality with important predictive ability. The area under the curve values for internal validation of our prediction model and Clinical Risk Index for Babies-II scores were 0.81 and 0.76, and for external validation, 0.80 and 0.51, respectively. Moreover, the Hosmer-Lemeshow test showed that our model has a constant degree of calibration. CONCLUSIONS: There was good predictive accuracy for mortality of EPIs based on influencing factors prenatally and within 1 hour after delivery. Predicting the risk of mortality of EPIs as soon as possible after birth can effectively guide parents to be proactive in treating more EPIs with life-saving value. TRIAL REGISTRATION NUMBER: ChiCTR1900025234.


Assuntos
Lactente Extremamente Prematuro , Unidades de Terapia Intensiva Neonatal , Lactente , Recém-Nascido , Humanos , Feminino , Gravidez , Estudos Prospectivos , Idade Gestacional , Prognóstico
14.
Int Heart J ; 64(5): 928-934, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37778996

RESUMO

This study aims to examine the changes in myocardial microcirculation in rats in a high-altitude hypoxic environment via computed tomography (CT) myocardial perfusion imaging technology. Rats in two groups were raised in different environments from 4 weeks of age for a period of 24 weeks. At 28 weeks of age, both groups underwent CT myocardial perfusion scanning, and the following myocardial perfusion parameters were measured: time to peak (TTP), mean transit time (MTT), blood flow (BF), and blood volume (BV). Following the scan, the rats were sacrificed, the cardiac index and right ventricular hypertrophy index were obtained, and hematoxylin-eosin (HE) staining was utilized to observe the pathological changes in the myocardium. In the group of rats that are subject to a high-altitude hypoxic environment for 24 weeks (the high-altitude group), the TTP and MTT values were increased (P < 0.05), the BF and BV values were lower (P < 0.05), the right heart mass was higher (P < 0.05) than that in the low-altitude group. As shown by the pathological results of HE staining, the gap between cardiomyocytes in the high-altitude group was widened, the arrangement of cardiomyocytes was irregular, and the cells were filled with a few fat vacuoles. The myocardial microcirculation is altered in a high-altitude hypoxic environment. In particular, the myocardium is in a state of inadequate perfusion, the BF in the myocardium slows down, and the right heart displays compensatory hypertrophy.


Assuntos
Altitude , Imagem de Perfusão do Miocárdio , Ratos , Animais , Microcirculação , Tomografia Computadorizada por Raios X/métodos , Hipóxia , Miocárdio , Imagem de Perfusão
15.
Mikrochim Acta ; 190(10): 403, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37728643

RESUMO

An unsophisticated fluorescence-enabled strategy is brought forward to process the highly sensitive fluorescence detection of Salmonella typhimurium (S. typhimurium) which based on polyethyleneimine (PEI)-templated silver/copper nanoclusters (Ag/CuNCs) (λ excitation = 334 nm and λ emission = 466 nm) with cryonase-assisted target recycling amplification. The Ag/CuNCs nanoclusters are synthesized as fluorescent materials due to their strong and stable fluorescence characteristics and are modified with S. typhimurium aptamers to form aptamer-Ag/CuNCs probes. The probes can be adsorbed on the surface of quenching agents-polydopamine nanospheres (PDANSs), thereby inducing fluorescence quenching of the probes. Once the aptamers are bound to the target, the aptamers/targets complexes are separated from the PDANSs surface, and the Ag/CuNCs recover the fluorescence signal. The released complexes will immediately be transformed into a substrate digested by cryonase (an enzyme that can digest all types of nucleic acids), and the released targets are bound to another aptamers to initiate the next round of cleavage. This reaction will be repeated continuously until all relevant aptamers are consumed and all Ag/CuNCs are released, resulting in a significant amplification of the fluorescence signal and improved sensitivity. Using Ag/CuNCs as fluorescent probes combined with cryonase-assisted amplification strategy, the fluorescence aptasensor is constructed with detection limits as low as 3.8 CFU mL-1, which is tenfold better than without the cryonase assistance. The method developed has been applied to milk, orange juice, chicken, and egg white samples with excellent selectivity and accuracy providing an approach for the early and rapid detection of S. typhimurium in food.


Assuntos
Cobre , Salmonella typhimurium , Animais , Prata , Galinhas , Corantes Fluorescentes , Oligonucleotídeos
16.
Commun Biol ; 6(1): 855, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37591976

RESUMO

CRISPR-Cas systems endow the bacterial and archaeal species with adaptive immune mechanisms to fend off invading phages and foreign plasmids. The class 2 type VI CRISPR/Cas effector Cas13d has been harnessed to confer the protection against RNA viruses in diverse eukaryotic species. However a vast number of different viruses can potentially infect the same host plant resulting in mixed infection, thus necessitating the generation of crops with broad-spectrum resistance to multiple viruses. Here we report the repurposing of CRISPR/Cas13d coupled with an endogenous tRNA-processing system (polycistronic tRNA-gRNA, PTG) to target the multiple potato RNA viruses. Expression of Cas13d and four different gRNAs were observed in transgenic potato lines expressing the Cas13d/PTG construct. We show that the Cas13d/PTG transgenic plants exhibit resistance to either PVY, PVS, PVX or PLRV alone or two/three viruses simultaneously by reducing viral accumulation in plant cells. In sum, our findings provide an efficient strategy for engineering crops that can simultaneously resist infection by multiple RNA viruses.


Assuntos
Vírus de RNA , Solanum tuberosum , RNA , Solanum tuberosum/genética , Processamento Pós-Transcricional do RNA , Archaea , Produtos Agrícolas
17.
Planta ; 258(4): 70, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37620620

RESUMO

MAIN CONCLUSION: The Cas13a-based multiplex RNA targeting system can be engineered to confer resistance to RNA viruses, whereas the number and expression levels of gRNAs have no significant effect on viral interference. The CRISPR-Cas systems provide adaptive immunity to bacterial and archaeal species against invading phages and foreign plasmids. The class 2 type VI CRISPR/Cas effector Cas13a has been harnessed to confer the protection against RNA viruses in diverse eukaryotic species. However, whether the number and expression levels of guide RNAs (gRNAs) have effects on the efficiency of RNA virus inhibition is unknown. Here, we repurpose CRISPR/Cas13a in combination with an endogenous tRNA-processing system (polycistronic tRNA-gRNA) to target four genes of potato virus Y (PVY) with varying expression levels. We expressed Cas13a and four different gRNAs in potato lines, and the transgenic plants expressing multiple gRNAs displayed similar suppression of PVY accumulation and reduced disease symptoms as those expressing a single gRNA. Moreover, PTG/Cas13a-transformed plants with different expression levels of multiple gRNAs displayed similar resistance to PVY strains. Collectively, this study suggests that the Cas13a-based multiplex RNA targeting system can be utilized to engineer resistance to RNA viruses in plants, whereas the number and expression levels of gRNAs have no significant effect on CRISPR/Cas13a-mediated viral interference in plants.


Assuntos
Potyvirus , Potyvirus/genética , RNA , Sistemas CRISPR-Cas/genética , Plantas Geneticamente Modificadas/genética , Processamento Pós-Transcricional do RNA
18.
Front Microbiol ; 14: 1199994, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37405158

RESUMO

Anoplophora glabripennis (Coleoptera: Cerambycidae: Lamiinae) is an invasive wood borer pest that has caused considerable damage to forests. Gut bacteria are of great importance in the biology and ecology of herbivores, especially in growth and adaptation; however, change in the gut bacterial community of this pest feeding on different hosts is largely unknown. In this study, we investigated the gut bacterial communities of A. glabripennis larvae fed on different preferred hosts, Salix matsudana and Ulmus pumila, using 16S rDNA high-throughput sequencing technology. A total of 15 phyla, 25 classes, 65 orders, 114 families, 188 genera, and 170 species were annotated in the gut of A. glabripennis larvae fed on S. matsudana or U. pumila using a 97% similarity cutoff level. The dominant phyla were Firmicutes and Proteobacteria and the core dominant genera were Enterococcus, Gibbsiella, Citrobacter, Enterobacter, and Klebsiella. There was significantly higher alpha diversity in the U. pumila group than in the S. matsudana group, and principal co-ordinate analysis showed significant differences in gut bacterial communities between the two groups. The genera with significant abundance differences between the two groups were Gibbsiella, Enterobacter, Leuconostoc, Rhodobacter, TM7a, norank, Rhodobacter, and Aurantisolimonas, indicating that the abundance of larval gut bacteria was affected by feeding on different hosts. Further network diagrams showed that the complexity of the network structure and the modularity were higher in the U. pumila group than in the S. matsudana group, suggesting more diverse gut bacteria in the U. pumila group. The dominant role of most gut microbiota was related to fermentation and chemoheterotrophy, and specific OTUs positively correlated with different functions were reported. Our study provides an essential resource for the gut bacteria functional study of A. glabripennis associated with host diet.

19.
Sci China Life Sci ; 66(7): 1459-1481, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37335463

RESUMO

PIWI-clade proteins harness piRNAs of 24-33 nt in length. Of great puzzles are how PIWI-clade proteins incorporate piRNAs of different sizes and whether the size matters to PIWI/piRNA function. Here we report that a PIWI-Ins module unique in PIWI-clade proteins helps define the length of piRNAs. Deletion of PIWI-Ins in Miwi shifts MIWI to load with shorter piRNAs and causes spermiogenic failure in mice, demonstrating the functional importance of this regulatory module. Mechanistically, we show that longer piRNAs provide additional complementarity to target mRNAs, thereby enhancing the assembly of the MIWI/eIF3f/HuR super-complex for translational activation. Importantly, we identify a c.1108C>T (p.R370W) mutation of HIWI (human PIWIL1) in infertile men and demonstrate in Miwi knock-in mice that this genetic mutation impairs male fertility by altering the property of PIWI-Ins in selecting longer piRNAs. These findings reveal a critical role of PIWI-Ins-ensured longer piRNAs in fine-tuning MIWI/piRNA targeting capacity, proven essential for spermatid development and male fertility.


Assuntos
RNA de Interação com Piwi , Testículo , Humanos , Masculino , Camundongos , Animais , Testículo/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espermatogênese/genética , Proteínas/metabolismo , Fertilidade/genética , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo
20.
J Inflamm Res ; 16: 1555-1570, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082297

RESUMO

Purpose: HIV-infected immunological non-responders (INRs) failed to achieve the normalization of CD4+ T cell counts despite their undetectable viral load. INRs have an increased risk of clinical progressions of Acquired Immunodeficiency Syndrome (AIDS) and non-AIDS events, accompanied by higher mortality rates than immunological responders (IRs). This study aimed to discover the genes, which help to distinguish INRs from IRs and explore the possible mechanism of INRs. Methods: Screening DEGs between INRs and IRs using GEO microarray dataset GSE143742. DEG biological functions were investigated using GO and KEGG analysis. DEGs and WGCNA linked modules were intersected to find common genes. Key genes were identified using SVM-RFE and LASSO regression models. ROC analysis was done to evaluate key gene diagnostic effectiveness using GEO database dataset GSE106792. Cytoscape created a miRNA-mRNA-TF network for diagnostic genes. CIBERSORT and flow cytometry examined the INRs and IRs immune microenvironments. In 10 INR and 10 IR clinical samples, diagnostic gene expression was verified by RT-qPCR and Western blot. Results: We obtained 190 DEGs between the INR group and IR group. Functional enrichment analysis found a significant enrichment in mitochondria and apoptosis-related pathways. CD69 and ZNF207 were identified as potential diagnostic genes. CD69 and ZNF207 shared a transcription factor, NCOR1, in the miRNA-mRNA-TF network. Immune microenvironment analysis by CIBERSORT showed that IRs had a higher level of resting memory CD4+ T cells, lower level of activated memory CD4+ T cells and resting dendritic cells than INRs, as confirmed by flow cytometry analysis. In addition, CD69 and ZNF207 were correlated with immune cells. Experiments confirmed the expression of the diagnostic genes in INRs and IRs. Conclusion: CD69 and ZNF207 were identified as potential diagnostic genes to discriminate INRs from IRs. Our findings offered new clues to diagnostic and therapeutic targets for INRs.

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