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1.
J Virol ; 98(6): e0050724, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38775482

RESUMO

Viruses employ a series of diverse translational strategies to expand their coding capacity, which produces viral proteins with common domains and entangles virus-host interactions. P3N-PIPO, which is a transcriptional slippage product from the P3 cistron, is a potyviral protein dedicated to intercellular movement. Here, we show that P3N-PIPO from watermelon mosaic virus (WMV) triggers cell death when transiently expressed in Cucumis melo accession PI 414723 carrying the Wmr resistance gene. Surprisingly, expression of the P3N domain, shared by both P3N-PIPO and P3, can alone induce cell death, whereas expression of P3 fails to activate cell death in PI 414723. Confocal microscopy analysis revealed that P3N-PIPO targets plasmodesmata (PD) and P3N associates with PD, while P3 localizes in endoplasmic reticulum in melon cells. We also found that mutations in residues L35, L38, P41, and I43 of the P3N domain individually disrupt the cell death induced by P3N-PIPO, but do not affect the PD localization of P3N-PIPO. Furthermore, WMV mutants with L35A or I43A can systemically infect PI 414723 plants. These key residues guide us to discover some WMV isolates potentially breaking the Wmr resistance. Through searching the NCBI database, we discovered some WMV isolates with variations in these key sites, and one naturally occurring I43V variation enables WMV to systemically infect PI 414723 plants. Taken together, these results demonstrate that P3N-PIPO, but not P3, is the avirulence determinant recognized by Wmr, although the shared N terminal P3N domain can alone trigger cell death.IMPORTANCEThis work reveals a novel viral avirulence (Avr) gene recognized by a resistance (R) gene. This novel viral Avr gene is special because it is a transcriptional slippage product from another virus gene, which means that their encoding proteins share the common N-terminal domain but have distinct C-terminal domains. Amazingly, we found that it is the common N-terminal domain that determines the Avr-R recognition, but only one of the viral proteins can be recognized by the R protein to induce cell death. Next, we found that these two viral proteins target different subcellular compartments. In addition, we discovered some virus isolates with variations in the common N-terminal domain and one naturally occurring variation that enables the virus to overcome the resistance. These results show how viral proteins with common domains interact with a host resistance protein and provide new evidence for the arms race between plants and viruses.


Assuntos
Doenças das Plantas , Potyvirus , Proteínas Virais , Doenças das Plantas/virologia , Potyvirus/genética , Potyvirus/patogenicidade , Proteínas Virais/genética , Proteínas Virais/metabolismo , Cucumis melo/virologia , Resistência à Doença/genética , Morte Celular , Plasmodesmos/virologia , Plasmodesmos/metabolismo , Virulência , Cucurbitaceae/virologia , Interações Hospedeiro-Patógeno , Retículo Endoplasmático/virologia , Retículo Endoplasmático/metabolismo , Mutação , Citrullus/virologia
2.
Plant Physiol ; 194(3): 1447-1466, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-37962935

RESUMO

14-3-3 proteins play vital roles in plant defense against various pathogen invasions. To date, how 14-3-3 affects virus infections in plants remains largely unclear. In this study, we found that Nicotiana benthamiana 14-3-3h interacts with TRANSLATIONALLY CONTROLLED TUMOR PROTEIN (TCTP), a susceptibility factor of potato virus Y (PVY). Silencing of Nb14-3-3h facilitates PVY accumulation, whereas overexpression of Nb14-3-3h inhibits PVY replication. The antiviral activities of 3 Nb14-3-3h dimerization defective mutants are significantly decreased, indicating that dimerization of Nb14-3-3h is indispensable for restricting PVY infection. Our results also showed that the mutant Nb14-3-3hE16A, which is capable of dimerizing but not interacting with NbTCTP, has reduced anti-PVY activity; the mutant NbTCTPI65A, which is unable to interact with Nb14-3-3h, facilitates PVY replication compared with the wild-type NbTCTP, indicating that dimeric Nb14-3-3h restricts PVY infection by interacting with NbTCTP and preventing its proviral function. As a counter-defense, PVY 6K1 interferes with the interaction between Nb14-3-3h and NbTCTP by competitively binding to Nb14-3-3h and rescues NbTCTP to promote PVY infection. Our results provide insights into the arms race between plants and potyviruses.


Assuntos
Potyvirus , Viroses , Humanos , Proteínas 14-3-3 , Dimerização , Proteínas Virais/genética
3.
Biomacromolecules ; 25(3): 1972-1977, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38359265

RESUMO

A facile and green approach for the preparation of PEGn-NH2s from PEGn-N3s in water with DTT as the reduction reagent has been developed, avoiding the introduction of metal ions and difficulties in purification compared to the traditional synthesis process of PEGn-NH2s. A series of high-purity linear and multiarm PEGn-NH2s with different molecular weights were synthesized, demonstrating the versatility of this method. Additionally, HS-PEG45-NH2 with high fidelity of thiol and amine was easily prepared through the one-step two functional group conversion of N3-PEG45-S-S-PEG45-N3, and the PEG-based NH2-PEG@AuNPs were also prepared. This technology will promote the application of PEGn-NH2s in the fields of medicine and biomaterials.


Assuntos
Nanopartículas Metálicas , Polietilenoglicóis , Azidas , Ditiotreitol , Aminas , Ouro
4.
Lupus ; 33(2): 129-136, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158805

RESUMO

OBJECTIVE: The aim was to investigate the changes in retinal and choroidal thickness and vascular density in patients with systemic lupus erythematosus (SLE) using optical coherence tomography angiography (OCTA). METHODS: Twenty-nine patients with SLE (29 eyes) and 25 control subjects (25 eyes) were enrolled. SLE activity was assessed using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Retinal thickness (RT), inner retinal thickness (IRT), outer retinal thickness (ORT), choroidal thickness (ChT), retinal superficial vascular density (SVD), retinal deep vascular density (DVD), choriocapillary vascular density (CCVD), foveal avascular zone (FAZ), superficial FAZ (sFAZ), and deep FAZ (dFAZ) were measured using OCTA. The retinal and choroidal thickness and vascular density between the control group and SLE group were compared. The relationships between SLEDAI scores and the retinal and choroidal thickness and vascular density in SLE group were analyzed. RESULTS: The SVD was significantly increased, and the DVD and CCVD were significantly decreased in the SLE group compared to the control group (p < .05). The results of receiver operating characteristic (ROC) showed that the area under the curve (AUC) values of SVD, DVD, and CCVD were 0.873, 0.729, and 0.727, indicating a high accuracy in discriminating patients with SLE from controls. Correlation analysis showed that the SLEDAI scores were positively correlated with dFAZ (r = 0.589, p = .001) and FAZ (r = 0.451, p = .018), and negatively correlated with DVD (r = -0.491, p = .009) and CCVD (r = -0.521, p = .005). CONCLUSIONS: DVD and CCVD were decreased in the SLE and might be related to the disease activity. SVD, DVD, and CCVD may hold promise in the discovery of biomarkers for diagnosing SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Densidade Microvascular , Retina , Angiografia , Angiofluoresceinografia/métodos
5.
Plant Physiol ; 189(2): 754-771, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35294544

RESUMO

Triacylglycerol lipase (TGL) plays critical roles in providing energy for seed germination and plant development. However, the role of TGL in regulating plant virus infection is largely unknown. In this study, we adopted affinity purification coupled with mass spectrometry and identified that a maize (Zea mays) pathogenesis-related lipase protein Z. mays TGL (ZmTGL) interacted with helper component-proteinase (HC-Pro) of sugarcane mosaic virus (SCMV). Yeast two-hybrid, luciferase complementation imaging, and bimolecular fluorescence complementation assays confirmed that ZmTGL directly interacted with SCMV HC-Pro in vitro and in vivo. The 101-460 residues of SCMV HC-Pro were important for its interaction with ZmTGL. ZmTGL and SCMV HC-Pro co-localized at the mitochondria. Silencing of ZmTGL facilitated SCMV infection, and over-expression of ZmTGL reduced the RNA silencing suppression activity, most likely through reducing HC-Pro accumulation. Our results provided evidence that the lipase hydrolase activity of ZmTGL was associated with reducing HC-Pro accumulation, activation of salicylic acid (SA)-mediated defense response, and inhibition of SCMV infection. We show that ZmTGL inhibits SCMV infection by reducing HC-Pro accumulation and activating the SA pathway.


Assuntos
Potyvirus , Zea mays , Lipase/genética , Lipase/metabolismo , Doenças das Plantas , Potyvirus/fisiologia , Ácido Salicílico/metabolismo , Zea mays/genética
6.
Plant Physiol ; 189(1): 301-314, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35171294

RESUMO

Trichomes, the hair-like structures located on aerial parts of most vascular plants, are associated with a wide array of biological processes and affect the economic value of certain species. The processes involved in unicellular trichome formation have been well-studied in Arabidopsis (Arabidopsis thaliana). However, our understanding of the morphological changes and the underlying molecular processes involved in multicellular trichome development is limited. Here, we studied the dynamic developmental processes involved in glandular and nonglandular multicellular trichome formation in cucumber (Cucumis sativus L.) and divided these processes into five sequential stages. To gain insights into the underlying mechanisms of multicellular trichome formation, we performed a time-course transcriptome analysis using RNA-sequencing analysis. A total of 711 multicellular trichome-related genes were screened and a model for multicellular trichome formation was developed. The transcriptome and co-expression datasets were validated by reverse transcription-quantitative PCR and in situ hybridization. In addition, virus-induced gene silencing analysis revealed that CsHOMEOBOX3 (CsHOX3) and CsbHLH1 are involved in nonglandular trichome elongation and glandular trichome formation, respectively, which corresponds with the transcriptome data. This study presents a transcriptome atlas that provides insights into the molecular processes involved in multicellular trichome formation in cucumber and can be an important resource for future functional studies.


Assuntos
Arabidopsis , Cucumis sativus , Arabidopsis/genética , Cucumis sativus/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Transcriptoma/genética , Tricomas/genética
7.
Opt Express ; 31(15): 23974-23989, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475237

RESUMO

Fiber coupling plays an important role in applications such as free-space optical communication (FSOC) and self-referencing interferometry. However, the coupling efficiency is often affected by turbulence and platform vibrations, which requires dynamic coupling with optimization algorithms. In this paper, to further mitigate the effects of sudden disturbances and to expand the effective range of fiber coupling systems, we propose a new method called the advanced root mean square propagation with warm-up (ARW) algorithm. By adaptively adjusting both the gain rate and the perturbation rate with warm-up operations, the ARW algorithm can achieve higher effective range and acceptable steady-state coupling efficiency simultaneously. Simulation and experimental results demonstrate that the proposed method requires only 36.4% of the iterations of the SPGD algorithm to deal with sudden disturbances. Moreover, the effective range of the ARW algorithm is 530.50µrad in the specific coupling platform, which is 20% higher than the effective range of SPGD.

8.
BMC Infect Dis ; 23(1): 462, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430239

RESUMO

BACKGROUND: B7-H3 is an important immune checkpoint molecule that plays a negative role in immune regulation. This study was aimed to explore B7-H3 expression in HIV-infected patients and its clinical significance. METHODS: To explore the expression and clinical significance of B7-H3 in HIV-infected patients, we investigated the B7-H3 expression pattern and the correlation of B7-H3 expression with clinical parameters of HIV-infected patients with different levels of CD4+ T cells. To assess the role of B7-H3 in regulating the function of T cells in HIV infection, we performed a proliferation assay and T cell function test in vitro. RESULTS: B7-H3 expression in HIV-infected patients was significantly higher than that in healthy controls. mB7-H3 expression on CD4+CD25high T cells and CD14+ monocytes increased with disease progression. mB7-H3 expression on CD4+CD25high T cells and monocytes was negatively correlated with lymphocyte count, CD4+T cell count, and positively correlated with HIV viral load in HIV-infected patients. when the number of CD4+ T cells in HIV-infected patients was ≥ 200/µL, sB7-H3 and mB7-H3 expression levels on CD4+CD25high T cells and monocytes were negatively correlated with lymphocyte count, CD4+T cell count. sB7-H3 and mB7-H3 expression on monocytes were positively correlated with HIV viral load. B7-H3 inhibited the proliferation of lymphocytes and the secretion of IFN-γ in vitro, especially the ability of CD8+ T cells to secrete IFN-γ. CONCLUSIONS: B7-H3 played an important negative regulatory role in anti-HIV infection immunity. It could be used as a potential biomarker for the progression of HIV infection and a novel target for the treatment of HIV infection.


Assuntos
Linfócitos T CD8-Positivos , Infecções por HIV , Humanos , Relevância Clínica , Monócitos , Plasma , Bioensaio , Fatores de Transcrição
9.
J Nanobiotechnology ; 21(1): 44, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747224

RESUMO

Photoreceptor degeneration is one of the major causes of progressive blindness which lacks of curative treatment. GW2580, a highly selective inhibitor of colony-stimulating factor 1 receptor, has the protective potential on neurons; however, little was known about the application of GW2580 on photoreceptor degeneration. In this study, BV-2 and 661W cells coculture system was constructed to investigate the interaction between microglia and photoreceptors. GW2580 was loaded into zeolitic imidazolate framework-90-rhodamine B (ZIF-90-RhB) to synthesize a novel kind of nanoparticles, namely, ZIF-90-RhB-GW2580, through a one-step self-assembly approach. A photoreceptor degeneration model was generated by intense light exposure in zebrafish and ZIF-90-RhB-GW2580 nanoparticles were delivered by the intraocular injection. The results showed that in vitro GW2580 treatment promoted phenotypic transformation in microglia and led to the blockade of photoreceptor apoptosis. Following the intraocular delivery of ZIF-90-RhB-GW2580 nanoparticles, the microglial proliferation and inflammatory response were significantly inhibited; moreover, the photoreceptors underwent alleviated injury with a recovery of retinal structure and visual function. In conclusion, the intraocular injection of ZIF-90-RhB-GW2580 at the early stage enables the precise delivery and sustained release of the GW2580, thus preventing the progression of photoreceptor degeneration.


Assuntos
Nanopartículas , Degeneração Retiniana , Zeolitas , Animais , Peixe-Zebra , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/prevenção & controle
10.
Plant Physiol ; 186(2): 853-864, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33764466

RESUMO

Cucurbits are economically important crops worldwide. The genomic data of many cucurbits are now available. However, functional analyses of cucurbit genes and noncoding RNAs have been impeded because genetic transformation is difficult for many cucurbitaceous plants. Here, we developed a set of tobacco ringspot virus (TRSV)-based vectors for gene and microRNA (miRNA) function studies in cucurbits. A TRSV-based expression vector could simultaneously express GREEN FLUORESCENT PROTEIN (GFP) and heterologous viral suppressors of RNA silencing in TRSV-infected plants, while a TRSV-based gene silencing vector could knock down endogenous genes exemplified by PHYTOENE DESATURASE (PDS) in Cucumis melo, Citrullus lanatus, Cucumis sativus, and Nicotiana benthamiana plants. We also developed a TRSV-based miRNA silencing vector to dissect the functions of endogenous miRNAs. Four representative miRNAs, namely, miR159, miR166, miR172, and miR319, from different cucurbits were inserted into the TRSV vector using a short tandem target mimic strategy and induced characteristic phenotypes in TRSV-miRNA-infected plants. This TRSV-based vector system will facilitate functional genomic studies in cucurbits.


Assuntos
Citrullus/genética , Cucumis sativus/genética , Vetores Genéticos , MicroRNAs/genética , Nepovirus/genética , Nicotiana/genética , Citrullus/virologia , Cucumis sativus/virologia , Técnicas de Silenciamento de Genes , Engenharia Genética , Proteínas de Fluorescência Verde , Oxirredutases/genética , Proteínas de Plantas/genética , Interferência de RNA , RNA de Plantas/genética , Nicotiana/virologia
11.
Plant Physiol ; 187(1): 174-186, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618134

RESUMO

Chloroplasts play an indispensable role in the arms race between plant viruses and hosts. Chloroplast proteins are often recruited by plant viruses to support viral replication and movement. However, the mechanism by which chloroplast proteins regulate potyvirus infection remains largely unknown. In this study, we observed that Nicotiana benthamiana ribosomal protein large subunit 1 (NbRPL1), a chloroplast ribosomal protein, localized to the chloroplasts via its N-terminal 61 amino acids (transit peptide), and interacted with tobacco vein banding mosaic virus (TVBMV) nuclear inclusion protein b (NIb), an RNA-dependent RNA polymerase. Upon TVBMV infection, NbRPL1 was recruited into the 6K2-induced viral replication complexes in chloroplasts. Silencing of NbRPL1 expression reduced TVBMV replication. NbRPL1 competed with NbBeclin1 to bind NIb, and reduced the NbBeclin1-mediated degradation of NIb. Therefore, our results suggest that NbRPL1 interacts with NIb in the chloroplasts, reduces NbBeclin1-mediated NIb degradation, and enhances TVBMV infection.


Assuntos
Proteínas de Cloroplastos/genética , Doenças das Plantas/genética , Potyvirus/fisiologia , Proteínas Virais/genética , Proteínas de Cloroplastos/metabolismo , Doenças das Plantas/virologia , Potyvirus/enzimologia , Nicotiana , Proteínas Virais/metabolismo
12.
Opt Express ; 30(3): 3793-3803, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209631

RESUMO

In this paper, a novel phase modulation technique based on a corner-cube reflector (CCR) array is proposed and demonstrated experimentally. The piezoceramics are linked behind each CCR. When the beams irradiate on the CCR array, the phase modulation can be realized by applying a voltage to piezoceramics to control the spatial location of each CCR. The piston phase errors of the device itself are compensated by employing the stochastic parallel gradient descent (SPGD) algorithm. Then, the piezoceramics are loaded with preset voltages to obtain the expected phase, and the anticipative optical field is generated. In the experiment, the piston phase errors of the 7-way and 19-way CCR array are corrected well. In order to further verify the phase control capability of the device, a vortex beam carrying orbital angular momentum (OAM) of 1 is generated by utilizing the 6-way CCR array. The experimental results confirm the feasibility of the concept.

13.
Opt Lett ; 47(2): 365-368, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35030607

RESUMO

We demonstrated a beam conformal projection system for coherent combining of large-scale lasers over 2.1 km in turbulence 20 m above the ground, using the basic modules of a 19-element fiber phased array combined with coarse pointing by a gimbal mount. After coarse pointing and aberration corrections, the metrics (reflected light) of the combined beams from a basic module were best increased by 13.4 times, suggesting that our system promises the great effect of coherent combining under long-distance turbulence. Moreover, we tentatively realized coherent combining of two basic modules (38 lasers), which is the largest number of elements in a fiber laser coherent beam combination outdoors, to the best of our knowledge, with the metrics of combined beams increased by about 29 times.

14.
Fish Shellfish Immunol ; 121: 223-231, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34986398

RESUMO

Calcium/calmodulin-dependent protein kinase II is a downstream mediator of calcium signalling and participates in the regulation of various cellular physiological functions. In previous studies, the expression of Eriocheir sinensis CaMKII (EsCaMKII) was significantly decreased in the thoracic ganglion after Spiroplasma eriocheiris infection, as shown using TMT-based quantitative proteomic analysis; however, the specific functions of EsCaMKII are still unclear. In this study, the full-length cDNA of EsCaMKII was 3314 bp long, consisting of a 1605 bp open reading frame encoding a protein of 535 amino acids, including a 258 aa serine/threonine protein kinase catalytic domain (EsCaMKII-CD). EsCaMKII is highly transcribed in haemocytes, nerves (thoracic ganglion), gills, and muscles, but lowly transcribed in the hepatopancreas, heart, and intestines. The transcription levels of EsCaMKII were altered in E. sinensis haemocytes after S. eriocheiris infection. After the over-expression of EsCaMKII-CD in RAW264.7 cells, the apoptosis rate of RAW264.7 cells was significantly increased. After the over-expression of EsCaMKII-CD, the morphology of RAW264.7 cells became worse after being infected with S. eriocheiris. Meanwhile, the copy number of S. eriocheiris in RAW264.7 cells was significantly decreased. From 48 h to 96 h after EsCaMKII RNA interference, the transcription levels of EsCaMKII decreased significantly. The transcription of apoptosis genes and cell apoptosis were also inhibited in haemocytes after EsCaMKII RNAi. The knockdown of EsCaMKII by RNAi resulted in significant increases in the copy number of S. eriocheiris and in the mortality of crabs during S. eriocheiris infection. These results indicate that EsCaMKII could promote the apoptosis of E. sinensis and enhance its ability to resist S. eriocheiris infection.


Assuntos
Apoptose , Braquiúros , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Infecções por Bactérias Gram-Negativas , Spiroplasma , Animais , Braquiúros/enzimologia , Braquiúros/microbiologia , Sinalização do Cálcio , Infecções por Bactérias Gram-Negativas/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Camundongos , Proteômica , Células RAW 264.7 , Spiroplasma/patogenicidade
15.
Anal Bioanal Chem ; 414(3): 1389-1402, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34741181

RESUMO

Aggregation-induced electrochemiluminescence reagent, a distyrylbenzene derivative with donor-acceptor conjugated nanosheet structure, namely TPAPCN, was used as a trace label and modified on the electrode through the formation of classical sandwich complex of antibody-antigen-antibody in this work. In aggregate state, TPAPCN with twisted structure was limited in nanometer space through intermolecular π - π stacking interactions, which not only restricts the intramolecular motions but also combines a large number of singlet excitons to greatly trigger electrochemiluminescence (ECL). The ECL signal of this system enhanced with more captured cytokeratin 19 fragment 21-1 (CYFRA21-1) on the modified electrode. Three-dimensional graphene/platinum nanoparticles with large specific surface, and excellent electroconductivity and biocompatibility were prepared and acted as excellent carriers for thionine handling (3D-GN/PtNPs/Th), which was employed for improving the loading of antibodies and generating internal electrochemical signal. Consequently, a novel ratiometric sandwich immunosensor for CYFRA21-1 detection was fabricated based on TPAPCN and 3D-GN/PtNPs/Th, that is, a rapid and reliable detection was achieved through the ratio between ECL and electrochemical signals. The prepared sensor performed good linearity in the range of 50 fg/mL to 1 ng/mL with a detection limit as low as 16 fg/mL. Moreover, the detection results revealed well in the analysis of human serum samples, demonstrating a significant application for clinical monitoring and biomolecules detection.


Assuntos
Anticorpos Imobilizados/química , Antígenos de Neoplasias/sangue , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Queratina-19/sangue , Estirenos/química , Técnicas Biossensoriais/métodos , Grafite/química , Humanos , Limite de Detecção , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Platina/química
16.
Phytopathology ; 112(2): 441-451, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34191551

RESUMO

Potyviral coat protein (CP) is involved in the replication and movement of potyviruses. However, little information is available on the roles of CP-coding sequence in potyviral infection. Here, we introduced synonymous substitutions to the codon C574G575C576 coding conserved residue arginine at position 192 (R192) of tobacco vein banding mosaic virus (TVBMV) CP. Substitution of the codon C574G575C576 to A574G575A576 or A574G575G576, but not C574G575A576, C574G575T576, or C574G575G576, reduced the replication, cell-to-cell movement, and accumulation of TVBMV in Nicotiana benthamiana plants, suggesting that C574 was critical for replication of TVBMV. Nucleotides 531 to 576 of the TVBMV CP-coding sequence were predicted to form a stem-loop structure, in which four consecutive C-G base pairs (C576-G531, C532-G575, C574-G533, and C534-G573) were located at the stem. Synonymous substitutions of R178-codon C532G533C534 to A532G533A534 and A532G533G534, but not C532G533A534, C532G533T534, or C532G533G534, reduced the replication levels, cell-to-cell, and systemic movement of TVBMV, suggesting that C532 was critical for TVBMV replication. Synonymous substitutions disrupting base pairs C576-G531 and C534-G573 did not affect viral accumulation. After three serial-passage inoculations, the accumulation of spontaneous mutant viruses was restored, and codons A532G533A534, A532G533G534, A574G575A576, or A574G575G576 of mutants were each separately changed to C532G533A534, C532G533G534, C574G575A576, or C574G575G576. Synonymous mutation of R178 and R192 also reduced viral accumulation in N. tabacum plants. Therefore, we concluded that the two consecutive C532-G575 and C574-G533 base pairs played critical roles in TVBMV replication via maintaining the stability of the stem-loop structures formed by nucleotides 531 to 576 of the CP-coding sequence.


Assuntos
Doenças das Plantas , Potyvirus , Fases de Leitura Aberta , Potyvirus/genética , RNA Viral/genética , Nicotiana , Replicação Viral
17.
Int J Med Sci ; 19(4): 618-630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35582419

RESUMO

N6-methyladenosine (m6A) RNA methylation has been implicated in various malignancies. This study aimed to identify prognostic signature based on m6A methylation regulators for hepatocellular carcinoma (HCC) and provide candidate targets for HCC treatment. In this study, the expression levels, prognostic values, correlation with tumor grades and genetic variations of m6A-related genes in HCC were evaluated using bioinformatics analyses. Interestingly, the results show that methyltransferase zinc finger CCCH-type containing 13 (ZC3H13) was expressed at a significantly low level in HCC. Survival outcome analysis suggested that significant correlations existed between ZC3H13 downregulation and poor overall survival (OS) and poor recurrence-free survival (RFS) in HCC patients. Therefore, ZC3H13 was chosen for further experimental validation. The expression of ZC3H13 in HCC cell lines was investigated by western blotting. Knockdown of ZC3H13 significantly enhanced the migration and invasion of HCC cells, as demonstrated by wound healing and transwell assays. Moreover, upregulating ZC3H13 repressed the growth of xenograft tumors in vivo. Functional and pathway enrichment analyses indicated that ZC3H13 might be involved in transcriptional dysregulation or the JAK-STAT signaling pathway in cancer. Additionally, ZC3H13 expression was significantly correlated with lymphocytes and immunomodulators. Therefore, ZC3H13 is a promising candidate as a novel biomarker and therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Nucleares , Proteínas de Ligação a RNA , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Metilação , Prognóstico , RNA/metabolismo
18.
J Clin Lab Anal ; 36(2): e24211, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34967040

RESUMO

BACKGROUND: Presently, the global spread of COVID-19 is still going on, with more than 0.6 million new cases confirmed per day (as of November 20, 2021). However, since China entered a post-epidemic phase in mid-March 2020, the daily number of new domestic infections in the Chinese mainland has been maintained at almost zero or single digits, which was attributed to a series of effective measures for COVID-19 prevention and control adopted by the Chinese government. Among these measures, SARS-CoV-2 nucleic acid testing holds key role for the timely confirmation and isolation of the infections to prevent further transmission. METHODS: Referring to the national policy requirements, since April 30, 2020, The Affiliated Hospital of Qingdao University has conducted SARS-CoV-2 nucleic acid testing in its PCR laboratory for patients and social workers, as well as for environmental monitoring and employee screening. As of mid-November 2020, the daily amount of single-tube samples for nucleic acid testing rose above 4,000. RESULTS: In this article, a rapid and highly effective approach for SARS-CoV-2 nucleic acid daily testing is presented, allowing five technicians to complete nucleic acid testing in 6,500 single-tube samples in one day with a high level of quality. Using this approach, since the samples entered the PCR laboratory, all testing results were reported in 2.5-3 h with satisfactory quality control and precise reporting criterion as prerequisites. CONCLUSION: This testing approach provides a referable workflow for other testing institutions and is expected to play an important role in COVID-19 prevention and control.


Assuntos
COVID-19 , Técnicas de Amplificação de Ácido Nucleico , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/prevenção & controle , China , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/normas , Técnicas de Amplificação de Ácido Nucleico/estatística & dados numéricos , Controle de Qualidade , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Fatores de Tempo
19.
Nano Lett ; 21(16): 7021-7029, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34369781

RESUMO

Hydrogen ion is an attractive charge carrier for energy storage due to its smallest radius. However, hydrogen ions usually exist in the form of hydronium ion (H3O+) because of its high dehydration energy; the choice of electrode materials is thus greatly limited to open frameworks and layered structures with large ionic channels. Here, the desolvation of H3O+ is achieved by using anatase TiO2 as anodes, enabling the H+ intercalation with a strain-free characteristic. Density functional theory calculations show that the desolvation effects are dependent on the facets of anatase TiO2. Anatase TiO2 (001) surface, a highly reactive surface, impels the desolvation of H3O+ into H+. When coupled with a MnO2 cathode, the proton battery delivers a high specific energy of 143.2 Wh/kg at an ultrahigh specific power of 47.9 kW/kg. The modulation of the interactions between ions and electrodes opens new perspectives for battery optimizations.

20.
Mol Plant Microbe Interact ; 34(6): 658-668, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33534601

RESUMO

Potyviruses move to neighboring cells in the form of virus particles or a coat protein (CP)-containing ribonucleoprotein complex. However, the precise roles of RNA-binding residues in potyviral CP in viral cell-to-cell movement remain to be elucidated. In this study, we predicted the three-dimensional model of tobacco vein banding mosaic virus (TVBMV)-encoded CP and found nine residues presumably located in the CP RNA-binding pocket. Substitutions of the two basic residues at positions 192 and 225 (R192 and K225) with either alanine, cysteine, or glutamic acid abolished TVBMV cell-to-cell and systemic movement in Nicotiana benthamiana plants. These substitutions also reduced the replication of the mutant viruses. Results from the electrophoretic mobility shift assay showed that the RNA-binding activity of mutant CPs derived from R192 or K225 substitutions was significantly lower than that of wild-type CP. Analysis of purified virus particles showed that mutant viruses with R192 or K225 substitutions formed RNA-free virus-like particles. Mutations of R192 and K225 did not change the CP plasmodesmata localization. The wild-type TVBMV CP could rescue the deficient cell-to-cell movement of mutant viruses. Moreover, deletion of any of the other seven residues also abolished TVBMV cell-to-cell movement and reduced the CP RNA-binding activity. The corresponding nine residues in watermelon mosaic virus CP were also found to play essential roles in virus cell-to-cell movement. In conclusion, residues R192 and K225 in the CP RNA-binding pocket are critical for viral RNA binding and affect both virus replication and cell-to-cell movement.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Proteínas do Capsídeo , Nicotiana , Proteínas do Capsídeo/genética , Potyvirus , RNA Viral/genética , Nicotiana/genética , Replicação Viral
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