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1.
BMC Plant Biol ; 24(1): 311, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649805

RESUMO

BACKGROUND: Brassica napus, a hybrid resulting from the crossing of Brassica rapa and Brassica oleracea, is one of the most important oil crops. Despite its significance, B. napus productivity faces substantial challenges due to heavy metal stress, especially in response to cadmium (Cd), which poses a significant threat among heavy metals. Natural resistance-associated macrophage proteins (NRAMPs) play pivotal roles in Cd uptake and transport within plants. However, our understanding of the role of BnNRAMPs in B. napus is limited. Thus, this study aimed to conduct genome-wide identification and bioinformatics analysis of three Brassica species: B. napus, B. rapa, and B. oleracea. RESULTS: A total of 37 NRAMPs were identified across the three Brassica species and classified into two distinct subfamilies based on evolutionary relationships. Conservative motif analysis revealed that motif 6 and motif 8 might significantly contribute to the differentiation between subfamily I and subfamily II within Brassica species. Evolutionary analyses and chromosome mapping revealed a reduction in the NRAMP gene family during B. napus evolutionary history, resulting in the loss of an orthologous gene derived from BoNRAMP3.2. Cis-acting element analysis suggested potential regulation of the NRAMP gene family by specific plant hormones, such as abscisic acid (ABA) and methyl jasmonate (MeJA). However, gene expression pattern analyses under hormonal or stress treatments indicated limited responsiveness of the NRAMP gene family to these treatments, warranting further experimental validation. Under Cd stress in B. napus, expression pattern analysis of the NRAMP gene family revealed a decrease in the expression levels of most BnNRAMP genes with increasing Cd concentrations. Notably, BnNRAMP5.1/5.2 exhibited a unique response pattern, being stimulated at low Cd concentrations and inhibited at high Cd concentrations, suggesting potential response mechanisms distinct from those of other NRAMP genes. CONCLUSIONS: In summary, this study indicates complex molecular dynamics within the NRAMP gene family under Cd stress, suggesting potential applications in enhancing plant resilience, particularly against Cd. The findings also offer valuable insights for further understanding the functionality and regulatory mechanisms of the NRAMP gene family.


Assuntos
Brassica , Proteínas de Plantas , Estresse Fisiológico , Brassica/genética , Estudo de Associação Genômica Ampla , Genoma de Planta , Proteínas de Plantas/genética , Genes de Plantas , Cádmio/metabolismo , Cádmio/toxicidade , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Proteínas de Transporte de Cátions/genética , Estresse Fisiológico/genética , Fenômenos Fisiológicos Vegetais
2.
Front Microbiol ; 15: 1367725, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481789

RESUMO

Soil microorganisms and enzymes play crucial roles in soil organic carbon (SOC) sequestration by promoting soil aggregate formation and stability and by participating in SOC cycling and accumulation. However, the effects by which soil microorganisms and enzymes act as mediators driving dynamic changes in SOC during rapid urbanization remain unclear. Therefore, this study selected the built-up area of Nanchang City, China (505 km2), as the study area. Sampling surveys were conducted using 184 sample plots stratified based on the proportion of impermeable surface area to distinguish different urbanization levels. The driving factors of dynamic changes in SOC of different aggregates during the process of urbanization were analyzed using the soil microbial community and enzyme activities. The results demonstrated that with an increase in urbanization intensity, both SOC content and stock exhibited a significant decline (p < 0.05). The highest SOC stock and contribution rate were observed in the 0.25-1 mm aggregates, and they were significantly influenced by urbanization (p < 0.05). In addition, the biomass of gram-positive bacteria (G+) and actinomycetota, and the activities of N-acetylglucosaminidase and acid phosphatase (AP) were significantly higher in low-urbanization areas than in high-urbanization areas (p < 0.05). SOC of each aggregate was positively correlated with fungi, arbuscular mycorrhizal fungi, G+, gram-negative bacteria, actinomycetota, protozoa, ß-1,4-glucosidase, N-acetylglucosaminidase, AP, urease, and catalase. Compared to soil enzymes, soil microorganisms exhibited a greater role in SOC sequestration (22.7%). Additionally, a structural equation model indicated that urbanization can directly or indirectly lead to a decrease in SOC of aggregates by altering soil physicochemical properties and affecting microbial and enzyme dynamics. However, the larger vegetation characteristics index mitigate the negative impacts of urbanization on SOC. Overall, urbanization had a negative impact on soil carbon storage. In the future, it is important to consider strategies that focus on improving soil nutrients, maintaining soil structure, protecting existing urban trees, and enhancing plant diversity during the urbanization process. These measures can help increase soil microbial biomass and enzyme activity, thereby improving soil and aggregate-related SOC content. The study could contribute to enhancing carbon sequestration in urban greenspaces.

3.
Animals (Basel) ; 13(21)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37958152

RESUMO

Newly found biochemical characteristics of the placenta can provide new insights for further studies on the possible markers of physiological/pathological pregnancy or the function of the placenta. We compared the proteome of the dairy cow placenta after enzymatic hydrolysis by three different proteases using a label-free mass spectrometry approach. In total, 541, 136, and 86 proteins were identified in the trypsin group (TRY), pepsin group (PEP), and papain group (PAP). By comparing the proteome of the PAP and TRY, PEP and TRY, and PEP and PAP groups, 432, 421, and 136 differentially expressed proteins were identified, respectively. We compared the up-regulated DEPs and down-regulated DEPs of each comparison group. The results show that the proteins identified by papain were mostly derived from the extracellular matrix and collagen, and were enriched in the relaxin signaling pathway and AGE-RAGE signaling pathway in diabetic complications; pepsin digestion was able to identify more muscle-related proteins, which were enriched in the lysosome, platelet activation, cardiac muscle contraction, the bacterial invasion of epithelial cells, and small cell lung cancer; trypsin mainly enzymatically degraded the extracellular matrix, blood particles, and cell-surface proteins that were enriched in arginine and proline metabolism, olfactory transduction proteasome, protein processing in the endoplasmic reticulum, pyruvate metabolism, and arrhythmogenic right ventricular cardiomyopathy (ARVC). In summary, these results provide insights into the discovery of the physiological functions of dairy cow placenta and the selection of proteases in dairy cow placenta proteomics.

4.
Opt Lett ; 48(18): 4725-4728, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707887

RESUMO

Using a CZ-grown a-cut Pr:YLF crystal as laser gain medium after processing it into crystal fiber, we have demonstrated real Pr3+-doped single-crystal fiber lasers for the first time to the best of our knowledge. This Pr3+ crystal fiber has absorbed up to 20.4 W of pump power, which is the highest absorbed power among Pr3+ lasers. For two representative laser emissions at about 639 nm and 607 nm, we have achieved maximum output powers of 5.45 W and 3.04 W, respectively. Output powers of the two lasers show very good linearities, which indicate that the present output powers are only limited by the available pump power. Both laser emissions have exhibited near diffraction-limited beam qualities. This proposal has provided a good and feasible route for the development of compact, high-power, and high-brightness all-solid-state Pr3+ visible lasers via crystal fiber.

5.
Antioxidants (Basel) ; 12(5)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237870

RESUMO

Oligomeric Proanthocyanidins (OPCs), as a class of compounds widely found in plants, are particularly abundant in grapes and blueberries. It is a polymer comprising many different monomers, such as catechins and epicatechins. The monomers are usually linked to each other by two types of links, A-linkages (C-O-C) and B-linkages (C-C), to form the polymers. Numerous studies have shown that compared to high polymeric procyanidins, OPCs exhibit antioxidant properties due to the presence of multiple hydroxyl groups. This review describes the molecular structure and natural source of OPCs, their general synthesis pathway in plants, their antioxidant capacity, and potential applications, especially the anti-inflammatory, anti-aging, cardiovascular disease prevention, and antineoplastic functions. Currently, OPCs have attracted much attention, being non-toxic and natural antioxidants of plant origin that scavenge free radicals from the human body. This review would provide some references for further research on the biological functions of OPCs and their application in various fields.

6.
Plants (Basel) ; 12(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36903884

RESUMO

High levels of cadmium (Cd) in soil can cause crop yield reduction or death. Cadmium accumulation in crops affects human and animal health as it passes through the food chain. Therefore, a strategy is needed to enhance the tolerance of crops to this heavy metal or reduce its accumulation in crops. Abscisic acid (ABA) plays an active role in plants' response to abiotic stress. The application of exogenous ABA can reduce Cd accumulation in shoots of some plants and enhance the tolerance of plants to Cd; therefore, ABA may have good application prospects. In this paper, we reviewed the synthesis and decomposition of ABA, ABA-mediated signal transduction, and ABA-mediated regulation of Cd-responsive genes in plants. We also introduced physiological mechanism underlying Cd tolerance because of ABA. Specifically, ABA affects metal ion uptake and transport by influencing transpiration and antioxidant systems, as well as by affecting the expression of metal transporter and metal chelator protein genes. This study may provide a reference for further research on the physiological mechanism of heavy metal tolerance in plants.

7.
Chemosphere ; 299: 134377, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35364075

RESUMO

Dissolved organic matter (DOM) is a complex mixture of organic molecules that plays an important role in freshwater lake ecosystems. Excitation emission matrix-parallel factor analysis (EEM-PARAFAC) is an important tool for the identification and source analysis of DOM but is still inadequate for studying the differences and quantifying the contributions of different sources. Here, based on the maximum fluorescence intensities (Fmax) of the four fluorescent components (e.g., protein-like component C1, and the humic-like components C2, C3, C4) identified by EEM-PARAFAC, combined with large-scale data obtained from observations at Erhai Lake, we used partial least squares path modeling (PLS-PM) to improve the understanding of the migration and transformation mechanisms of DOM. The results showed that the phytoplankton and trophic state had greater impacts on DOM, while the impacts of sediment and inflow rivers were less significant. The results of the models that used nitrogen nutrients (N) and phosphorus nutrients (P) to separately indicate the trophic state suggested that the driving force of P on DOM was stronger than that of N in Erhai Lake. Among the four fluorescent components, the protein-like component with the largest relative proportion (41.98%) was mainly affected by phytoplankton, which was consistent with the autogenic characteristics obtained through spontaneous source index (BIX). The duality of the humic-like components was consistent with the duality of DOM through fluorescent index (FI). C3 had a higher sensitivity to the trophic state than the other components, and C2 received the greatest positive contribution from the rivers entering the lake. These results provide an improved insight into the influence of different sources on the behavior of DOM and demonstrate the potential of using PLS-PM to study the complex driving mechanism of aquatic biogeochemical parameters.


Assuntos
Lagos , Matéria Orgânica Dissolvida , Ecossistema , Análise Fatorial , Substâncias Húmicas/análise , Lagos/química , Espectrometria de Fluorescência , Qualidade da Água
8.
Nat Commun ; 12(1): 6124, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675210

RESUMO

A variety of organic cages with different geometries have been developed during the last decade, most of them exhibiting a single cavity. In contrast, the number of organic cages featuring a pair of cavities remains scarce. These structures may pave the way towards novel porous materials with emergent properties and functions.We herein report on rational design of a three-dimensional hexaformyl precursor 1, which exhibits two types of conformers, i.e. Conformer-1 and -2, with different cleft positions and sizes. Aided by molecular dynamics simulations, we select two triamino conformation capturers (denoted CC). Small-sized CC-1 selectively capture Conformer-1 by matching its cleft size, while the large-sized CC-2 is able to match and capture both conformers. This strategy allows the formation of three compounds with twin cavities, which we coin diphane. The self-assembly of diphane units results in superstructures with tunable proton conductivity, which reaches up to 1.37×10-5 S cm-1.

9.
J Org Chem ; 85(4): 2456-2465, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31916760

RESUMO

Herein, we report a method for in situ generation of N-aryliminium ions via reactions of N,N-dimethylanilines with diiodomethane. We used the method to prepare tetrahydroquinolines via one-pot three-component reactions between N,N-dimethylanilines, diiodomethane, and olefins. This transformation involves initial reaction of the aniline with diiodomethane to form an iodomethylammonium salt, which undergoes fragmentation accompanied by elimination of methyl iodide to give an N-aryliminium ion, which is trapped by the olefin via [4 + 2] cycloaddition to give the final product. This method for generating N-aryliminium ions requires neither a catalyst nor a strong oxidant, suggesting that it can be expected to find broad utility, especially for substrates that are sensitive to Lewis acids, transition metals, or strong oxidants.

10.
Biomater Sci ; 7(6): 2383-2393, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30916683

RESUMO

The capture of circulating tumor cells (CTCs) plays a crucial role in the early diagnosis, personalized treatment and postoperative evaluation of malignant tumors. In this study, UV-curable coating technology was combined with antibody immobilization to enable CTC captures on poly(methyl methacrylate) (PMMA) substrates. Controlled amounts of carboxyl groups and polyethylene glycol (PEG) segments were introduced into the coating formulation to facilitate immobilization of antibodies and block non-specific protein adsorption, respectively. Then, anti-EpCAM antibodies were immobilized on functionalized, coated PMMA substrates by EDC/NHS chemistry. Multiple physical, chemical and biological properties were investigated, including hydrophilicity, protein adsorption, platelet adhesion and anticoagulant properties. Thereafter, optimized coatings were applied on the inner wall of PMMA tubes, followed by immobilization of anti-EpCAM antibodies. After perfusion of the tubes with whole blood, enriched with SGC7901 gastric cancer cells that overexpress EpCAM antigens, rapid and efficient capture of the tumor cells was observed. These results provide a basis for further development of devices for the selective capture and enrichment of CTCs, using small blood volumes.


Assuntos
Separação Celular/métodos , Células Neoplásicas Circulantes/patologia , Raios Ultravioleta , Adsorção , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Adesão Celular , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial/imunologia , Humanos , Polietilenoglicóis/química , Polimetil Metacrilato/química , Soroalbumina Bovina/química
11.
Angew Chem Int Ed Engl ; 57(46): 15096-15100, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30211963

RESUMO

We prepared a new class of chiral C2 -symmetric bicyclic bisborane catalysts by addition reactions of internal dienes with the Piers borane, HB(C6 F5 )2 , and an analogue, HB(p-C6 F4 H)2 . The dependence of the addition pattern on the reaction temperature allowed us to selectively prepare two diastereomeric catalysts from a single diene precursor. The bisboranes prepared in situ exhibited excellent activity (turnover numbers up to 200 at -40 °C) and enantioselectivity (up to 95 % ee) in imine hydrogenation reactions.

12.
Angew Chem Int Ed Engl ; 56(14): 4028-4032, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28266171

RESUMO

Catalytic amounts of B(C6 F5 )3 promote the ring opening and subsequent isomerization of a series of unactivated cyclopropanes to afford terminal olefins in good yields when a hydrosilane and 2,6-dibromopyridine are employed as additives.

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