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1.
J Virol ; : e0091124, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240112

RESUMO

2C is a highly conserved picornaviral non-structural protein with ATPase activity and plays a multifunctional role in the viral life cycle as a promising target for anti-picornavirus drug development. While the structure-function of enteroviral 2Cs have been well studied, cardioviral 2Cs remain largely uncharacterized. Here, an endogenous ATP molecule was identified in the crystal structure of 2C from encephalomyocarditis virus (EMCV, Cardiovirus A). The ATP is bound into the ATPase active site with a unique compact conformation. Notably, the γ-phosphate of ATP directly interacts with Arg311 (conserved in cardioviral 2Cs), and its mutation significantly inhibits the ATPase activity. Unexpectedly, this mutation remarkably promotes 2C self-oligomerization and viral replication efficiency. Molecular dynamic simulations showed that the Arg311 side chain is highly dynamic, indicating it may function as a switch between the activation state and the inhibition state of ATPase activity. A hexameric ring model of EMCV 2C full length indicated that the C-terminal helix may get close to the N-terminal amphipathic helices to form a continuous positive region for RNA binding. The RNA-binding studies of EMCV 2C revealed that the RNA length is closely associated with the RNA-binding affinities and indicated that the substrate may wrap around the outer surface of the hexamer. Our studies provide a biochemical framework to guide the characterization of EMCV 2C and the essential role of arginine in cardioviral 2C functions. IMPORTANCE: Encephalomyocarditis virus (Cardiovirus A) is the causative agent of the homonymous disease, which may induce myocarditis, encephalitis, and reproductive disorders in various mammals. 2C protein is functionally indispensable and a promising target for drug development involving broad-spectrum picornaviral inhibitors. Here, an endogenous ATP molecule with a unique conformation was discovered by a combination of protein crystallography and high-performance liquid chromatography in the encephalomyocarditis virus (EMCV) 2C structure. Biochemical and structural characterization analysis of EMCV 2C revealed the critical role of conserved Arg311 in ATPase activity and self-oligomerization of EMCV 2C. The viral replication kinetics and infectivity study suggested that the residue negatively regulated the infectivity titer and virus encapsulation efficiency of EMCV and is, therefore, crucial for 2C protein to promote viral replication. Our systemic structure-function analysis provides unique insights into the function and regulation mechanism of cardioviral 2C protein.

2.
Plant Dis ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39190840

RESUMO

Yellowhorn (Xanthoceras sorbifolium) is a deciduous shrub or small tree native to China. The content of oil in kernels is 52.7% to 58.0%, of which is the source of neuroic acid (3.7-4.4%). (Liang et al. 2022). In recent years, yellowhorn, as a woody oleiferous crop, has been cultivated in northern China (Xiao et al. 2023). In late June 2019, an unknown collar rot was observed on yellowhorn in Tai'an, and Weifang City, Shandong Province, China. Infected plants had dark brown to black lesions at the base of the stem, about 10 to 15 cm from the ground, bark dehiscence and rot, resulting in wilting, withering, and death of plants. The disease incidence in the field was 35-48%. Representative symptomatic samples were collected randomly from the collar of 8 plants, and 24 samples were cut from the diseased tissue into 5 mm square pieces, surface disinfected with 75% alcohol for 30s and then with 0.1% mercury bichloride for 1min, plated onto potato dextrose agar (PDA), and incubated at 28°C in the dark for 2 to 3 days. Isolation frequency of the pathogen from symptomatic collar was 83.3%. The colonies were subcultured three times on PDA to obtained the purified colonies. The colonies appeared flocculent mycelia incubated on PDA at 28°C for 7 days. The color of the surface and the reverse colony was white and cream, respectively. The chlamydosposres were smooth with thick walled, and are formed singly. Microconidia were oval or ellipsoidal, with 0-1 septum; macroconidia end cells curved to slightly, with 3- or 5-septate, and measured 17.3 to 23.1 × 4.9 to 6.5 µm (avg. 21.3 × 5.9 µm, n = 60). The morphological characteristics fit the descriptions of Fusarium spp. (Hafizi et al. 2013; Crespo et al 2019). Genomic DNA extracted from four representative isolates (XSTA4, XSTA7, XSWF6 and XSWF8), and the internal transcribed spacer region (ITS) of ribosomal DNA, translation elongation factor 1-alpha (EF1-α), RNA polymerase I beta subunit (RPB1), and RNA polymerase II beta subunit (RPB2) genes were amplified using the primer pairs ITS1/ITS4 (White et al. 1990), EF-1/EF-2, RPB-1F/1R, and RPB2-5F2/11aR (O'Donnell et al 2010), respectively. Amplicons were sequenced and compared in GenBank using a BLAST analysis. The ITS sequences (OR672118, OR669008, OR669039, and OR669279) had 100% similarity with the sequences of F. solani (MT560378, MG561938, MN989030 and OP630608, respectively). The EF1-α sequences (OR934984, OR934985, OR934986, and OR934987) matched 100% with the sequences of F. solani (OQ511088, MW332044, MW620166 and MT379886). The RPB-1 sequences (PP896852, PP896853, PP896854, and PP896855) had 100% similarity with the sequences of F. solani (OL474057, OR916019, MT305118 and MT305118, respectively). The RPB2 sequences (PP896856, PP896857, PP896858, and PP896859) matched 100% with the sequences of F. solani (OR371884, OK880266, OP784447 and OL474055, respectively). A phylogenetic analysis based on ITS, RPB2 and EF1-α sequences placed the four obtained isolates within the same clade containing the F. solani isolates A6, 91-84-1 and UCR1780. Pathogenicity tests were carried out in late-June 2020. Fifty 120-day-old healthy seedlings were wounded with 2 mm deep at stems in the collar region of plants at 5 cm above the soil for tested. The seedlings were inoculated on the wound with 3-mm mycelial discs from a 7-day-old culture of each four representative strains of 10 repeated, respectively. Ten seedlings inoculated on the wound with sterile PDA served as control. All plants were grown in an incubator with a 28°C temperature. After 20 days, the stems which were inoculated the representative strain turned brown, with 2 - 5 cm length lesion, and the plants developed typical wilting and withering symptoms which similar to those observed in the field. The control remained asymptomatic. The pathogen was reisolated from the inoculated stems and its identity confirmed with both morphology and using molecular tools. These results indicated that the pathogens of yellowhorn collar rot is F. solani. To our knowledge, this is the first report of F. solani causing collar rot of yellowhorn in China.

3.
Hortic Res ; 11(7): uhae148, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988616

RESUMO

Walnut anthracnose (Colletotrichum gloeosporioides) reduces walnut yield and quality and seriously threatens the healthy development of the walnut industry. WRKY transcription factors (TFs) are crucial regulatory factors involved in plant-pathogen interactions. Our previous transcriptome analysis results indicate that JrWRKY4 responds to infection by C. gloeosporioides, but its specific regulatory network and disease resistance mechanism are still unclear. Herein, the characteristics of JrWRKY4 as a transcription activator located in the nucleus were first identified. Gain-of-function and loss-of-function analyses showed that JrWRKY4 could enhance walnut resistance against C. gloeosporioides. A series of molecular experiments showed that JrWRKY4 directly interacted with the promoter region of JrSTH2L and positively regulated its expression. In addition, JrWRKY4 interacted with JrVQ4 to form the protein complex, which inhibited JrWRKY4 for the activation of JrSTH2L. Notably, a MYB TF JrPHL8 interacting with the JrWRKY4 promoter has also been identified, which directly bound to the MBS element in the promoter of JrWRKY4 and induced its activity. Our study elucidated a novel mechanism of the JrPHL8-JrWRKY4-JrSTH2L in regulating walnut resistance to anthracnose. This mechanism improves our understanding of the molecular mechanism of WRKY TF mediated resistance to anthracnose in walnut, which provides new insights for molecular breeding of disease-resistant walnuts in the future.

4.
BMC Plant Biol ; 24(1): 653, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987678

RESUMO

BACKGROUND: Walnut anthracnose caused by Colletotrichum gloeosporioides seriously endangers the yield and quality of walnut, and has now become a catastrophic disease in the walnut industry. Therefore, understanding both pathogen invasion mechanisms and host response processes is crucial to defense against C. gloeosporioides infection. RESULTS: Here, we investigated the mechanisms of interaction between walnut fruits (anthracnose-resistant F26 fruit bracts and anthracnose-susceptible F423 fruit bracts) and C. gloeosporioides at three infection time points (24hpi, 48hpi, and 72hpi) using a high-resolution time series dual transcriptomic analysis, characterizing the arms race between walnut and C. gloeosporioides. A total of 20,780 and 6670 differentially expressed genes (DEGs) were identified in walnut and C. gloeosporioides against 24hpi, respectively. Generous DEGs in walnut exhibited opposite expression patterns between F26 and F423, which indicated that different resistant materials exhibited different transcriptional responses to C. gloeosporioides during the infection process. KEGG functional enrichment analysis indicated that F26 displayed a broader response to C. gloeosporioides than F423. Meanwhile, the functional analysis of the C. gloeosporioides transcriptome was conducted and found that PHI, SignalP, CAZy, TCDB genes, the Fungal Zn (2)-Cys (6) binuclear cluster domain (PF00172.19) and the Cytochrome P450 (PF00067.23) were largely prominent in F26 fruit. These results suggested that C. gloeosporioides secreted some type of effector proteins in walnut fruit and appeared a different behavior based on the developmental stage of the walnut. CONCLUSIONS: Our present results shed light on the arms race process by which C. gloeosporioides attacked host and walnut against pathogen infection, laying the foundation for the green prevention of walnut anthracnose.


Assuntos
Colletotrichum , Juglans , Doenças das Plantas , Juglans/microbiologia , Juglans/genética , Colletotrichum/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , RNA-Seq , Frutas/microbiologia , Frutas/genética , Transcriptoma , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Resistência à Doença/genética
5.
Nanoscale ; 16(28): 13654-13662, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38963285

RESUMO

I-III-VI quantum dots (QDs) have gained widespread attention owing to their significant advantages of non-toxicity, large structural tolerance, and efficient photoluminescence potential. However, the disbalance of reactivity between the elements will result in undesired products and compromised optical properties. Reducing the activity of highly reactive group IB elements is the most common approach, but it will reduce the overall reactivity and lead to a wide dispersion of QD sizes. In this study, we propose a method to improve the overall reactivity of the reaction system using the highly active IIIA precursor InI3, which triggers rapid nucleation and promotes the formation of Ag(In,Ga)S2 (AIGS) QDs, resulting in monodisperse particle size distributions and a significantly improved photoluminescence quantum yield (PLQY) (from 12% to 72%). Furthermore, narrow band edge emission is realized by coating a gallium sulfide (GaSx) shell on the basis of obtaining high-quality AIGS QDs. The core/shell QDs exhibit a 90% PLQY with a full width at half maximum (FWHM) of only 31 nm at 530 nm. This study provides a viable design strategy to synthesize monodisperse AIGS QDs with a narrow peak width and efficient luminescence, promoting the application of AIGS QDs in the field of luminescent displays.

6.
Int J Biol Macromol ; 275(Pt 2): 133671, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971274

RESUMO

Vaccination is the most effective method for preventing infectious diseases. Oral vaccinations have attracted much attention due to the ability to boost intestinal and systemic immunity. The focus of this study was to develop a poly (lactide-co-glycolide) acid (PLGA)-based ternary polyelectrolyte complex (PEC) with chitosan, sodium alginate, and transmembrane peptides R8 for the delivery of antigen proteins. In this study, the antigen protein (HBf), consisting of the Mycobacterium avium subspecies paratuberculosis (MAP) antigens HBHA, Ag85B, and Bfra, was combined with R8 to generate self-assembled conjugates. The results showed that PEC presented a cross-linked reticular structure to protect the encapsulated proteins in the simulated gastric fluid. Then, the nanocomposite separated into individual nanoparticles after entering the simulated intestinal fluid. The ternary PEC with R8 promoted the in vivo uptake of antigens by intestinal lymphoid tissue. Moreover, the ternary PEC administered orally to mice promoted the secretion of specific antibodies and intestinal mucosal IgA. In addition, in the mouse models of MAP infection, the ternary PEC enhanced splenic T cell responses, thus reducing bacterial load and liver pathology score. These results suggested that this ternary electrolyte complex could be a promising delivery platform for oral subunit vaccine candidates, not limited to MAP infection.


Assuntos
Alginatos , Quitosana , Imunidade nas Mucosas , Quitosana/química , Alginatos/química , Animais , Imunidade nas Mucosas/efeitos dos fármacos , Camundongos , Administração Oral , Polieletrólitos/química , Feminino , Camundongos Endogâmicos BALB C , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/química , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/química
7.
Int Immunopharmacol ; 137: 112384, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38878484

RESUMO

Selenium nanoparticles (SeNPs) enhance the immune response as adjuvants, increasing the efficacy of viral vaccines, including those for COVID-19. However, the efficiency of mucosal SeNPs in boosting vaccine-induced protective immunity against tuberculosis remains unclear. Therefore, this study aims to investigate whether the combination of SeNPs with the AH antigen (Ag85A-HspX) can boost respiratory mucosal immunity and thereby enhance the protective effects against tuberculosis. We synthesized SeNPs and assessed their impact on the immune response and protection against Mycobacterium bovis (M. bovis) as a mucosal adjuvant in mice, administered intranasally at a dose of 20 µg. SeNPs outperformed polyinosinic-polycytidylic acid (Poly IC) in stimulating the maturation of bone marrow-derived dendritic cells (BMDCs), which enhanced antigen presentation. SeNPs significantly activated and proliferated tissue-resident memory T cells (TRMs) and effector CD4+ T cells in the lungs. The vaccines elicited specific antibody responses in the respiratory tract and stimulated systemic Th1 and Th17 immune responses. Immunization with AH and SeNPs led to higher levels of mucosal secretory IgA in bronchoalveolar lavage fluid (BALF) and secretory IL-17 in splenocytes. Moreover, SeNPs immunized mice showed reduced M. bovis infection loads and inflammatory lesions in the lungs post-challenge. Notably, immunization with AH and SeNPs significantly reduced bacterial load in the lungs, achieving the lowest levels compared to all other tested groups. This study calls for pre-clinical investigation of AHB-SeNPs as an anti-bovine tuberculosis vaccine and for exploring its human vaccine potential, which is anticipated to aid in the development of innovative vaccines or adjuvants.


Assuntos
Adjuvantes Imunológicos , Antígenos de Bactérias , Imunidade nas Mucosas , Mycobacterium bovis , Nanopartículas , Selênio , Animais , Mycobacterium bovis/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Nanopartículas/administração & dosagem , Camundongos , Adjuvantes Imunológicos/administração & dosagem , Feminino , Antígenos de Bactérias/imunologia , Camundongos Endogâmicos C57BL , Tuberculose/imunologia , Tuberculose/prevenção & controle , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Vacinas contra a Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Pulmão/imunologia , Pulmão/microbiologia , Proteínas de Bactérias/imunologia
8.
J Synchrotron Radiat ; 31(Pt 4): 791-803, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38904937

RESUMO

A novel insertion device is introduced, designated as the Mango wiggler, designed for synchrotron radiation (SR) imaging that provides a large field of view. This innovative device is constructed from two orthogonal planar wigglers with a small difference in their period lengths, eliciting the phase difference of the magnetic fields to incrementally transitions from 0 to π/2. Such a configuration enlarges the vertical divergence of the light source, as with the horizontal divergence. The appellation `Mango wiggler' derives from the distinctive mango-shaped contour of its radiation field. A comprehensive suite of theoretical analyses and simulations has been executed to elucidate the radiation properties of the Mango wiggler, employing SPECTRA and Mathematica as calculation tools. In conjunction with the ongoing construction of the High Energy Photon Source in Beijing a practical Mango wiggler device has been fabricated for utilization in SR imaging applications. Theoretical analyses were applied to this particular Mango wiggler to yield several theoretical conclusions, and several simulations were performed according to the measured magnetic field results.

9.
J Infect Dis ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843067

RESUMO

HIF-1α is a pivotal regulator of metabolic and inflammatory responses. This study investigated the role of HIF-1α in M. bovis infection and its effects on host immune metabolism and tissue damage. We evaluated the expression of immunometabolism markers and MMPs infected with M. bovis, and following HIF-1α inhibition in vitro. To understand the implications of HIF-1α inhibition on disease progression, mice at different infection stages were treated with the HIF-1α inhibitor, YC-1. Our results revealed an upregulation of the HIF-1α in macrophages post-M. bovis infection, facilitating enhanced M1 macrophage polarization. The blockade of HIF-1α moderated these responses but escalated MMP activity, hindering bacterial control. Consistent with our in vitro results, early-stage treatment of mice with YC-1 aggravated pathological alterations and tissue damage, while late-stage HIF-1α inhibition proved beneficial in managing the disease. Overall, our findings underscored the nuanced role of HIF-1α across varying phases of M. bovis infection.

10.
IUCrJ ; 11(Pt 4): 502-509, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38727172

RESUMO

X-ray scattering/diffraction tensor tomography techniques are promising methods to acquire the 3D texture information of heterogeneous biological tissues at micrometre resolution. However, the methods suffer from a long overall acquisition time due to multi-dimensional scanning across real and reciprocal space. Here, a new approach is introduced to obtain 3D reciprocal information of each illuminated scanning volume using mathematic modeling, which is equivalent to a physical scanning procedure for collecting the full reciprocal information required for voxel reconstruction. The virtual reciprocal scanning scheme was validated by a simulated 6D wide-angle X-ray diffraction tomography experiment. The theoretical validation of the method represents an important technological advancement for 6D diffraction tensor tomography and a crucial step towards pervasive applications in the characterization of heterogeneous materials.

11.
Nucleic Acids Res ; 52(14): 8454-8465, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38769061

RESUMO

Riboswitches are conserved regulatory RNA elements participating in various metabolic pathways. Recently, a novel RNA motif known as the folE RNA motif was discovered upstream of folE genes. It specifically senses tetrahydrofolate (THF) and is therefore termed THF-II riboswitch. To unravel the ligand recognition mechanism of this newly discovered riboswitch and decipher the underlying principles governing its tertiary folding, we determined both the free-form and bound-form THF-II riboswitch in the wild-type sequences. Combining structural information and isothermal titration calorimetry (ITC) binding assays on structure-based mutants, we successfully elucidated the significant long-range interactions governing the function of THF-II riboswitch and identified additional compounds, including alternative natural metabolites and potential lead compounds for drug discovery, that interact with THF-II riboswitch. Our structural research on the ligand recognition mechanism of the THF-II riboswitch not only paves the way for identification of compounds targeting riboswitches, but also facilitates the exploration of THF analogs in diverse biological contexts or for therapeutic applications.


Assuntos
Conformação de Ácido Nucleico , Riboswitch , Tetra-Hidrofolatos , Riboswitch/genética , Tetra-Hidrofolatos/química , Tetra-Hidrofolatos/metabolismo , Ligantes , Modelos Moleculares , Dobramento de RNA , Motivos de Nucleotídeos , Mutação
12.
ACS Biomater Sci Eng ; 10(5): 3387-3400, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38656158

RESUMO

Given the worldwide problem posed by enteric pathogens, the discovery of safe and efficient intestinal adjuvants combined with novel antigen delivery techniques is essential to the design of mucosal vaccines. In this work, we designed poly (lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs) to codeliver all-trans retinoic acid (atRA), novel antigens, and CpG. To address the insolubility of the intestinal adjuvant atRA, we utilized PLGA to encapsulate atRA and form a "nanocapsid" with polydopamine. By leveraging polydopamine, we adsorbed the water-soluble antigens and the TLR9 agonist CpG onto the NPs' surface, resulting in the pathogen-mimicking PLPCa NPs. In this study, the novel fusion protein (HBf), consisting of the Mycobacterium avium subspecies paratuberculosis antigens HBHA, Ag85B, and Bfra, was coloaded onto the NPs. In vitro, PLPCa NPs were shown to promote the activation and maturation of bone marrow-derived dendritic cells. Additionally, we found that PLPCa NPs created an immune-rich microenvironment at the injection site following intramuscular administration. From the results, the PLPCa NPs induced strong IgA levels in the gut in addition to enhancing powerful systemic immune responses. Consequently, significant declines in the bacterial burden and inflammatory score were noted in PLPCa NPs-treated mice. In summary, PLPCa can serve as a novel and safe vaccine delivery platform against gut pathogens, such as paratuberculosis, capable of activating both systemic and intestinal immunity.


Assuntos
Nanopartículas , Paratuberculose , Animais , Nanopartículas/química , Paratuberculose/imunologia , Paratuberculose/prevenção & controle , Camundongos , Tretinoína/química , Tretinoína/farmacologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/química , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Intestinos/imunologia , Intestinos/microbiologia , Camundongos Endogâmicos C57BL , Feminino , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/administração & dosagem , Vacinas Bacterianas/imunologia , Camundongos Endogâmicos BALB C
13.
ACS Omega ; 9(11): 12927-12940, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524431

RESUMO

Irregular coal pillars inevitably appear in the layout of the current long-wall mining method, which easily forms stress concentrations and becomes a heavy disaster area of rock burst. In order to solve the impact risk of irregular coal pillar working face, it is necessary to study the instability mechanism of the coal pillar and put forward effective prevention and control measures. Based on the research background of 14320 working face of the Dongtan Coal Mine in the Yanzhou mining area of China, this paper studies the prediction and prevention of rock bursts in this kind of coal pillar by means of theoretical calculation, numerical simulation, engineering analogy, and field monitoring. The results show that (1) the absolute stability of coal pillar is that the width of coal pillar B reaches twice the support pressure of 2L, and the possibility of instability from large to small is coal pillars 2, 5, 3, 1, and 4. (2) The ratio of coal pillar strength to its average load determines the stability coefficient of the coal pillar, and it is judged that coal pillars 1 and 4 are in a stable state, coal pillars 3 and 5 are in a limit equilibrium state, and coal pillar 2 is in an unstable state. The numerical simulation shows that the maximum stress value inside the coal pillar during the mining process is basically consistent with the theoretical calculation of the bearing strength of the coal pillar. (3) The new evaluation method is used to evaluate the rock burst risk degree of the working face roadway: 156.75 m is a strong rock burst risk zone, 728.18 m is a medium rock burst risk zone, and 176.88 m is a weak rock burst risk zone. (4) Regional prevention and local prevention measures are proposed for the risk of rock burst in the roadway, which reduces the stress concentration of the coal pillar. It is verified that the pressure relief effect is remarkable, and the safe mining of such an irregular coal pillar working face is completed, which provides a solution for studying and solving such rock burst risk.

14.
Innovation (Camb) ; 5(1): 100539, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38089566

RESUMO

Synchrotron tomography experiments are transitioning into multifunctional, cross-scale, and dynamic characterizations, enabled by new-generation synchrotron light sources and fast developments in beamline instrumentation. However, with the spatial and temporal resolving power entering a new era, this transition generates vast amounts of data, which imposes a significant burden on the data processing end. Today, as a highly accurate and efficient data processing method, deep learning shows great potential to address the big data challenge being encountered at future synchrotron beamlines. In this review, we discuss recent advances employing deep learning at different stages of the synchrotron tomography data processing pipeline. We also highlight how applications in other data-intensive fields, such as medical imaging and electron tomography, can be migrated to synchrotron tomography. Finally, we provide our thoughts on possible challenges and opportunities as well as the outlook, envisioning selected deep learning methods, curated big models, and customized learning strategies, all through an intelligent scheduling solution.

15.
iScience ; 26(12): 108420, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38034346

RESUMO

With pre-trained large models and their associated fine-tuning paradigms being constantly applied in deep learning, the performance of large models achieves a dramatic boost, mostly owing to the improvements on both data quantity and quality. Next-generation synchrotron light sources offer ultra-bright and highly coherent X-rays, which are becoming one of the largest data sources for scientific experiments. As one of the most data-intensive scanning-based imaging methodologies, ptychography produces an immense amount of data, making the adoption of large deep learning models possible. Here, we introduce and refine the architecture of a neural network model to improve the reconstruction performance, through fine-tuning large pre-trained model using a variety of datasets. The pre-trained model exhibits remarkable generalization capability, while the fine-tuning strategy enhances the reconstruction quality. We anticipate this work will contribute to the advancement of deep learning methods in ptychography, as well as in broader coherent diffraction imaging methodologies in future.

16.
iScience ; 26(10): 107932, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37790277

RESUMO

Tomography experiments generate three-dimensional (3D) reconstructed slices from a series of two-dimensional (2D) projection images. However, the mechanical system generates joint offsets that result in unaligned 2D projections. This misalignment affects the reconstructed images and reduces their actual spatial resolution. In this study, we present a novel method called outer contour-based misalignment correction (OCMC) for correcting image misalignments in tomography. We use the sample's outer contour structure as auxiliary information to estimate the extent of misalignment in each image. This method is generic and can be used with various tomography imaging techniques. We validated our method with five datasets collected from different samples and across various tomography techniques. The OCMC method demonstrated significant advantages in terms alignment accuracy and time efficiency. As an end-to-end correction method, OCMC can be easily integrated into an online tomography data processing pipeline and facilitate feedback control in future synchrotron tomography experiments.

17.
Hortic Res ; 10(6): uhad086, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37786525

RESUMO

Walnut anthracnose induced by Colletotrichum gloeosporioides is a disastrous disease that severely restricts the development of the walnut industry in China. Long non-coding RNAs (lncRNAs) are involved in adaptive responses to disease, but their roles in the regulation of walnut anthracnose resistance response are not well defined. In this study, transcriptome analysis demonstrated that a C. gloeosporioides-induced lncRNA, lncRNA109897, located upstream from the target gene JrCCR4, upregulated the expression of JrCCR4. JrCCR4 interacted with JrTLP1b and promoted its transcriptional activity. In turn, JrTLP1b induced the transcription of lncRNA109897 to promote its expression. Meanwhile, transient expression in walnut leaves and stable transformation of Arabidopsis thaliana further proved that lncRNA, JrCCR4, and JrTLP1b improve the resistance of C. gloeosporioides. Collectively, these findings provide insights into the mechanism by which the lncRNA109897-JrCCR4-JrTLP1b transcriptional cascade regulates the resistance of walnut to anthracnose.

18.
J Synchrotron Radiat ; 30(Pt 6): 1086-1091, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729071

RESUMO

High-data-throughput and multimodal-acquisition experiments will prevail in next-generation synchrotron beamlines. Orchestrating dataflow pipelines connecting the data acquisition, processing, visualization and storage ends are becoming increasingly complex and essential for enhancing beamline performance. Mamba Data Worker (MDW) has been developed to address the data challenges for the forthcoming High Energy Photon Source (HEPS). It is an important component of the Mamba experimental control and data acquisition software ecosystem, which enables fast data acquisition and transmission, dynamic configuration of data processing pipelines, data multiplex in streaming, and customized data and metadata assembly. This paper presents the architecture and development plan of MDW, outlines the essential technologies involved, and illustrates its current application at the Beijing Synchrotron Radiation Facility (BSRF).

19.
mBio ; 14(5): e0164523, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37772878

RESUMO

IMPORTANCE: Sliding clamp is a highly conserved protein in the evolution of prokaryotic and eukaryotic cells. The sliding clamp is required for genomic replication as a critical co-factor of DNA polymerases. However, the sliding clamp analogs in viruses remain largely unknown. We found that the ASFV E301R protein (pE301R) exhibited a sliding clamp-like structure and similar functions during ASFV replication. Interestingly, pE301R is assembled into a unique ring-shaped homotetramer distinct from sliding clamps or proliferating cell nuclear antigens (PCNAs) from other species. Notably, the E301R gene is required for viral life cycle, but the pE301R function can be partially restored by the porcine PCNA. This study not only highlights the functional role of the ASFV pE301R as a viral sliding clamp analog, but also facilitates the dissection of the complex replication mechanism of ASFV, which provides novel clues for developing antivirals against ASF.


Assuntos
Vírus da Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Replicação Viral , DNA Polimerase Dirigida por DNA , Células Eucarióticas
20.
PLoS Pathog ; 19(5): e1011411, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37253057

RESUMO

Seneca virus A (SVA) is an emerging novel picornavirus that has recently been identified as the causative agent of many cases of porcine vesicular diseases in multiple countries. In addition to cleavage of viral polyprotein, the viral 3C protease (3Cpro) plays an important role in the regulation of several physiological processes involved in cellular antiviral responses by cleaving critical cellular proteins. Through a combination of crystallography, untargeted lipidomics, and immunoblotting, we identified the association of SVA 3Cpro with an endogenous phospholipid molecule, which binds to a unique region neighboring the proteolytic site of SVA 3Cpro. Our lipid-binding assays showed that SVA 3Cpro displayed preferred binding to cardiolipin (CL), followed by phosphoinositol-4-phosphate (PI4P) and sulfatide. Importantly, we found that the proteolytic activity of SVA 3Cpro was activated in the presence of the phospholipid, and the enzymatic activity is inhibited when the phospholipid-binding capacity decreased. Interestingly, in the wild-type SVA 3Cpro-substrate peptide structure, the cleavage residue cannot form a covalent binding to the catalytic cysteine residue to form the acyl-enzyme intermediate observed in several picornaviral 3Cpro structures. We observed a decrease in infectivity titers of SVA mutants harboring mutations that impaired the lipid-binding ability of 3Cpro, indicating a positive regulation of SVA infection capacity mediated by phospholipids. Our findings reveal a mutual regulation between the proteolytic activity and phospholipid-binding capacity in SVA 3Cpro, suggesting that endogenous phospholipid may function as an allosteric activator that regulate the enzyme's proteolytic activity during infection.


Assuntos
Cisteína Endopeptidases , Picornaviridae , Animais , Suínos , Cisteína Endopeptidases/metabolismo , Proteases Virais 3C/metabolismo , Peptídeo Hidrolases/metabolismo , Regulação Alostérica , Fosfolipídeos , Proteínas Virais/metabolismo
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