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1.
Nature ; 613(7943): 280-286, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631649

RESUMO

Macroscopic electric motors continue to have a large impact on almost every aspect of modern society. Consequently, the effort towards developing molecular motors1-3 that can be driven by electricity could not be more timely. Here we describe an electric molecular motor based on a [3]catenane4,5, in which two cyclobis(paraquat-p-phenylene)6 (CBPQT4+) rings are powered by electricity in solution to circumrotate unidirectionally around a 50-membered loop. The constitution of the loop ensures that both rings undergo highly (85%) unidirectional movement under the guidance of a flashing energy ratchet7,8, whereas the interactions between the two rings give rise to a two-dimensional potential energy surface (PES) similar to that shown by FOF1 ATP synthase9. The unidirectionality is powered by an oscillating10 voltage11,12 or external modulation of the redox potential13. Initially, we focused our attention on the homologous [2]catenane, only to find that the kinetic asymmetry was insufficient to support unidirectional movement of the sole ring. Accordingly, we incorporated a second CBPQT4+ ring to provide further symmetry breaking by interactions between the two mobile rings. This demonstration of electrically driven continual circumrotatory motion of two rings around a loop in a [3]catenane is free from the production of waste products and represents an important step towards surface-bound14 electric molecular motors.

2.
Nature ; 603(7900): 265-270, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264758

RESUMO

Molecular recognition1-4 and supramolecular assembly5-8 cover a broad spectrum9-11 of non-covalently orchestrated phenomena between molecules. Catalysis12 of such processes, however, unlike that for the formation of covalent bonds, is limited to approaches13-16 that rely on sophisticated catalyst design. Here we establish a simple and versatile strategy to facilitate molecular recognition by extending electron catalysis17, which is widely applied18-21 in synthetic covalent chemistry, into the realm of supramolecular non-covalent chemistry. As a proof of principle, we show that the formation of a trisradical complex22 between a macrocyclic host and a dumbbell-shaped guest-a molecular recognition process that is kinetically forbidden under ambient conditions-can be accelerated substantially on the addition of catalytic amounts of a chemical electron source. It is, therefore, electrochemically possible to control23 the molecular recognition temporally and produce a nearly arbitrary molar ratio between the substrates and complexes ranging between zero and the equilibrium value. Such kinetically stable supramolecular systems24 are difficult to obtain precisely by other means. The use of the electron as a catalyst in molecular recognition will inspire chemists and biologists to explore strategies that can be used to fine-tune non-covalent events, control assembly at different length scales25-27 and ultimately create new forms of complex matter28-30.

3.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36611257

RESUMO

Trans-splicing of a spliced leader (SL) to the 5' ends of mRNAs is used to produce mature mRNAs in several phyla of great importance to human health and the marine ecosystem. One of the consequences of the addition of SL sequences is the change or disruption of the open reading frames (ORFs) in the recipient transcripts. Given that most SL sequences have one or more of the trinucleotide NUG, including AUG in flatworms, trans-splicing of SL sequences can potentially supply a start codon to create new ORFs, which we refer to as slORFs, in the recipient mRNAs. Due to the lack of a tool to precisely detect them, slORFs were usually neglected in previous studies. In this work, we present the tool slORFfinder, which automatically links the SL sequences to the recipient mRNAs at the trans-splicing sites identified from SL-containing reads of RNA-Seq and predicts slORFs according to the distribution of ribosome-protected footprints (RPFs) on the trans-spliced transcripts. By applying this tool to the analyses of nematodes, ascidians and euglena, whose RPFs are publicly available, we find wide existence of slORFs in these taxa. Furthermore, we find that slORFs are generally translated at higher levels than the annotated ORFs in the genomes, suggesting they might have important functions. Overall, this study provides a tool, slORFfinder (https://github.com/songbo446/slORFfinder), to identify slORFs, which can enhance our understanding of ORFs in taxa with SL machinery.


Assuntos
RNA Líder para Processamento , Trans-Splicing , Humanos , RNA Líder para Processamento/genética , RNA Líder para Processamento/metabolismo , Fases de Leitura Aberta , Ecossistema , Sequência de Bases , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Splicing de RNA
4.
Proc Natl Acad Sci U S A ; 119(30): e2122335119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858433

RESUMO

Many cells specialize for different metabolic tasks at different times over their normal ZT cycle by changes in gene expression. However, in most cases, circadian gene expression has been assessed at the mRNA accumulation level, which may not faithfully reflect protein synthesis rates. Here, we use ribosome profiling in the dinoflagellate Lingulodinium polyedra to identify thousands of transcripts showing coordinated translation. All of the components in carbon fixation are concurrently regulated at ZT0, predicting the known rhythm of carbon fixation, and many enzymes involved in DNA replication are concurrently regulated at ZT12, also predicting the known rhythm in this process. Most of the enzymes in glycolysis and the TCA cycle are also regulated together, suggesting rhythms in these processes as well. Surprisingly, a third cluster of transcripts show peak translation at approximately ZT16, and these transcripts encode enzymes involved in transcription, translation, and amino acid biosynthesis. The latter has physiological consequences, as measured free amino acid levels increase at night and thus represent a previously undocumented rhythm in this model. Our results suggest that ribosome profiling may be a more accurate predictor of changed metabolic state than transcriptomics.


Assuntos
Aminoácidos , Ritmo Circadiano , Dinoflagellida , Biossíntese de Proteínas , Transcrição Gênica , Aminoácidos/biossíntese , Aminoácidos/genética , Ritmo Circadiano/genética , Dinoflagellida/genética , Dinoflagellida/metabolismo , RNA Mensageiro/metabolismo , Ribossomos/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(12): e2118573119, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35290119

RESUMO

Although catenanes comprising two ring-shaped components can be made in large quantities by templation, the preparation of three-dimensional (3D) catenanes with cage-shaped components is still in its infancy. Here, we report the design and syntheses of two 3D catenanes by a sequence of SN2 reactions in one pot. The resulting triply mechanically interlocked molecules were fully characterized in both the solution and solid states. Mechanistic studies have revealed that a suit[3]ane, which contains a threefold symmetric cage component as the suit and a tribromide component as the body, is formed at elevated temperatures. This suit[3]ane was identified as the key reactive intermediate for the selective formation of the two 3D catenanes which do not represent thermodynamic minima. We foresee a future in which this particular synthetic strategy guides the rational design and production of mechanically interlocked molecules under kinetic control.


Assuntos
Catenanos , Rotaxanos , Catenanos/química , Cinética , Rotaxanos/química
6.
J Am Chem Soc ; 146(21): 14835-14843, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38728105

RESUMO

The transformation of carbon dioxide (CO2) into functional materials has garnered considerable worldwide interest. Metal-organic frameworks (MOFs), as a distinctive class of materials, have made great contributions to CO2 capture and conversion. However, facile conversion of CO2 to stable porous MOFs for CO2 utilization remains unexplored. Herein, we present a facile methodology of using CO2 to synthesize stable zirconium-based MOFs. Two zirconium-based MOFs CO2-Zr-DEP and CO2-Zr-DEDP with face-centered cubic topology were obtained via a sequential desilylation-carboxylation-coordination reaction. The MOFs exhibit excellent crystallinity, as verified through powder X-ray diffraction and high-resolution transmission electron microscopy analyses. They also have notable porosity with high surface area (SBET up to 3688 m2 g-1) and good CO2 adsorption capacity (up to 12.5 wt %). The resulting MOFs have abundant alkyne functional moieties, confirmed through 13C cross-polarization/magic angle spinning nuclear magnetic resonance and Fourier transform infrared spectra. Leveraging the catalytic prowess of Ag(I) in diverse CO2-involved reactions, we incorporated Ag(I) into zirconium-based MOFs, capitalizing on their interactions with carbon-carbon π-bonds of alkynes, thereby forming a heterogeneous catalyst. This catalyst demonstrates outstanding efficiency in catalyzing the conversion of CO2 and propargylic alcohols into cyclic carbonates, achieving >99% yield at room temperature and atmospheric pressure conditions. Thus, this work provides a dual CO2 utilization strategy, encompassing the synthesis of CO2-based MOFs (20-24 wt % from CO2) and their subsequent application in CO2 capture and conversion processes. This approach significantly enhances overall CO2 utilization.

7.
BMC Plant Biol ; 24(1): 70, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38263006

RESUMO

BACKGROUND: The genus Sanicula L. is a unique perennial herb that holds important medicinal values. Although the previous studies on Sanicula provided us with a good research basis, its taxonomic system and interspecific relationships have not been satisfactorily resolved, especially for those endemic to China. Moreover, the evolutionary history of this genus also remains inadequately understood. The plastid genomes possessing highly conserved structure and limited evolutionary rate have proved to be an effective tool for studying plant phylogeny and evolution. RESULTS: In the current study, we newly sequenced and assembled fifteen Sanicula complete plastomes. Combined with two previously reported plastomes, we performed comprehensively plastid phylogenomics analyses to gain novel insights into the evolutionary history of this genus. The comparative results indicated that the seventeen plastomes exhibited a high degree of conservation and similarity in terms of their structure, size, GC content, gene order, IR borders, codon bias patterns and SSRs profiles. Such as all of them displayed a typical quadripartite structure, including a large single copy region (LSC: 85,074-86,197 bp), a small single copy region (SSC: 17,047-17,132 bp) separated by a pair of inverted repeat regions (IRs: 26,176-26,334 bp). And the seventeen plastomes had similar IR boundaries and the adjacent genes were identical. The rps19 gene was located at the junction of the LSC/IRa, the IRa/SSC junction region was located between the trnN gene and ndhF gene, the ycf1 gene appeared in the SSC/IRb junction and the IRb/LSC boundary was located between rpl12 gene and trnH gene. Twelve specific mutation hotspots (atpF, cemA, accD, rpl22, rbcL, matK, ycf1, trnH-psbA, ycf4-cemA, rbcL-accD, trnE-trnT and trnG-trnR) were identified that can serve as potential DNA barcodes for species identification within the genus Sanicula. Furthermore, the plastomes data and Internal Transcribed Spacer (ITS) sequences were performed to reconstruct the phylogeny of Sanicula. Although the tree topologies of them were incongruent, both provided strong evidence supporting the monophyly of Saniculoideae and Apioideae. In addition, the sister groups between Saniculoideae and Apioideae were strongly suggested. The Sanicula species involved in this study were clustered into a clade, and the Eryngium species were also clustered together. However, it was clearly observed that the sections of Sanicula involved in the current study were not respectively recovered as monophyletic group. Molecular dating analysis explored that the origin of this genus was occurred during the late Eocene period, approximately 37.84 Ma (95% HPD: 20.33-52.21 Ma) years ago and the diversification of the genus was occurred in early Miocene 18.38 Ma (95% HPD: 10.68-25.28 Ma). CONCLUSION: The plastome-based tree and ITS-based tree generated incongruences, which may be attributed to the event of hybridization/introgression, incomplete lineage sorting (ILS) and chloroplast capture. Our study highlighted the power of plastome data to significantly improve the phylogenetic supports and resolutions, and to efficiently explore the evolutionary history of this genus. Molecular dating analysis explored that the diversification of the genus occurred in the early Miocene, which was largely influenced by the prevalence of the East Asian monsoon and the uplift of the Hengduan Mountains (HDM). In summary, our study provides novel insights into the plastome evolution, phylogenetic relationships, taxonomic framework and evolution of genus Sanicula.


Assuntos
Apiaceae , Sanicula , Filogenia , Plastídeos , Cloroplastos
8.
Small ; : e2402083, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140166

RESUMO

Graphyne nanoscrolls (GNSs) have attracted significant research interest because of their wide-ranging applications. However, the production of GNSs via a self-scrolling approach is environment dependent. Here, molecular dynamics simulations are conducted to evaluate the self-scrolling behavior of an α-graphyne (α-GY) ribbon on a carbon nanotube (CNT) within various multiphysical environments, accounting for the interactions among temperature, electric field, and argon gas. The results demonstrate that the fabrication of an α-GNS lies in the interplay of van der Waals (vdW) forces among the components in a vacuum. Notably, the α-GY ribbon is easier to scroll onto a thicker CNT. The electric field attenuates the vdW interaction, necessitating thicker CNTs for successful self-scrolling under a stronger electric field. In argon, both the vdW interaction and nanoscale pore contribute to the overlap formation. At 300 K, increasing argon density prolongs the time required for α-GNS formation, with self-scrolling failing beyond a critical gas density threshold. Moreover, the self-scrolling becomes easier at higher temperatures. In multiphysical environments, the interplay between the electric field and the gas density dictates the self-scrolling at low temperatures. Finally, reasonable suggestions are given for successful self-scrolling. The conclusions offer valuable insights for the practical fabrication of α-GNS.

9.
Small ; 20(23): e2309371, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38169101

RESUMO

Construction of heterojunctions is an effective strategy to enhanced electrocatalytic oxygen evolution reaction (OER), but the structural evolution of the active phases and synergistic mechanism still lack in-depth understanding. Here, an FeOOH/Ni3S2 heterostructure supported on nickel foam (NF) through a two-step hydrothermal-chemical etching method is reported. In situ Raman spectroscopy study of the surface reconstruction behaviors of FeOOH/Ni3S2/NF indicates that Ni3S2 can be rapidly converted to NiOOH, accompanied by the phase transition from α-FeOOH to ß-FeOOH during the OER process. Importantly, a deep analysis of Ni─O bond reveals that the phase transition of FeOOH can regulate the lattice disorder of NiOOH for improved catalytic activity. Density functional theory (DFT) calculations further confirm that NiOOH/FeOOH heterostructure possess strengthened adsorption for O-containing intermediates, as well as lower energy barrier toward the OER. As a result, FeOOH/Ni3S2/NF exhibits promising OER activity and stability in alkaline conditions, requiring an overpotential of 268 mV @ 100 mA cm-2 and long-term stability over 200 h at a current density of 200 mA cm-2. This work provides a new perspective for understanding the synergistic mechanism of heterogeneous electrocatalysts during the OER process.

10.
Small ; 20(27): e2310908, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38279585

RESUMO

The high potassization/depotassization energy barriers and lack of efficient ion diffusion pathways are two serious obstacles for carbon-based materials to achieve satisfactory potassium ion storage performance. Herein, a facile and controllable one-step exfoliation-doping-etching strategy is proposed to construct heteroatoms (N, O, and S)-doped mesoporous few-layer carbon nanosheets (NOS-C). The mixed molten salts of KCl/K2SO4 are innovatively used as the exfoliators, dopants, and etching agents, which enable NOS-C with expanded interlayer spacing and uniformly distributed mesopores with the adjusted electronic structure of surrounding carbon atoms, contributing efficient dual (vertical and horizontal) K-ion diffusion pathways, low potassization/depotassization energy barriers and abundant active sites. Thus, the NOS anodes achieve a high reversible capacity of 516.8 mAh g-1 at 0.05 A g-1, superior rate capability of 202.8 mAh g-1 at 5 A g-1 and excellent long-term cyclic stability, and their practical application potential is demonstrated by the assembled potassium-ion full batteries. Moreover, a surface-interlayer synergetic K+ storage mechanism is revealed by a combined theoretical and experimental approach including in situ EIS, in situ Raman, ex situ XPS, and SEM analysis. The proposed K+ storage mechanism and unique structural engineering provide a new pathway for potassium-ion storage devices and even beyond.

11.
Brief Bioinform ; 23(4)2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35698834

RESUMO

Accurate prediction of open reading frames (ORFs) is important for studying and using genome sequences. Ribosomes move along mRNA strands with a step of three nucleotides and datasets carrying this information can be used to predict ORFs. The ribosome-protected footprints (RPFs) feature a significant 3-nt periodicity on mRNAs and are powerful in predicting translating ORFs, including small ORFs (sORFs), but the application of RPFs is limited because they are too short to be accurately mapped in complex genomes. In this study, we found a significant 3-nt periodicity in the datasets of populational genomic variants in coding sequences, in which the nucleotide diversity increases every three nucleotides. We suggest that this feature can be used to predict ORFs and develop the Python package 'OrfPP', which recovers ~83% of the annotated ORFs in the tested genomes on average, independent of the population sizes and the complexity of the genomes. The novel ORFs, including sORFs, identified from single-nucleotide polymorphisms are supported by protein mass spectrometry evidence comparable to that of the annotated ORFs. The application of OrfPP to tetraploid cotton and hexaploid wheat genomes successfully identified 76.17% and 87.43% of the annotated ORFs in the genomes, respectively, as well as 4704 sORFs, including 1182 upstream and 2110 downstream ORFs in cotton and 5025 sORFs, including 232 upstream and 234 downstream ORFs in wheat. Overall, we propose an alternative and supplementary approach for ORF prediction that can extend the studies of sORFs to more complex genomes.


Assuntos
Ribossomos , Genoma , Fases de Leitura Aberta , Ribossomos/genética , Ribossomos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Polimorfismo de Nucleotídeo Único
12.
Phys Rev Lett ; 132(26): 266201, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38996321

RESUMO

We propose helical topological superconductivity away from the Fermi surface in three-dimensional time-reversal-symmetric odd-parity multiband superconductors. In these systems, pairing between electrons originating from different bands is responsible for the corresponding topological phase transition. Consequently, a pair of helical topological Dirac surface states emerges at finite excitation energies. These helical Dirac surface states are tunable in energy by chemical potential and strength of band splitting. They are protected by time-reversal symmetry combined with crystalline twofold rotation symmetry. We suggest concrete materials in which this phenomenon could be observed.

13.
Langmuir ; 40(10): 5479-5487, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38421608

RESUMO

The fluorescent probe method has attracted significant research attention due to its high sensitivity and reproducibility in detecting bovine serum albumin (BSA). In this study, we constructed a fluorescent probe for BSA detection by assembling an amphiphilic organic fluorescent molecule, termed 2-(2'-hydroxyphenyl) benzothiazole (HBT-11), with BSA. In an aqueous solution, HBT-11 exhibited a weak fluorescence emission at 501 nm. However, the addition of BSA substantially enhanced the fluorescence emission at 501 nm, indicating that the assembly was driven by electrostatic interactions between HBT-11 and BSA. HBT-11, serving as a fluorescent probe for BSA detection, demonstrated a limit of detection (LOD) as low as 3.92 nmol L-1, excellent photostability, high selectivity, and robust anti-interference capability. Notably, we successfully applied HBT-11 for detecting BSA in fetal bovine serum and selectively imaging BSA in HeLa cells.


Assuntos
Corantes Fluorescentes , Soroalbumina Bovina , Humanos , Corantes Fluorescentes/toxicidade , Células HeLa , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos
14.
Ann Bot ; 134(2): 325-336, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38720433

RESUMO

BACKGROUND AND AIMS: There are intrinsic conflicts between signalling to mutualists and concealing (camouflaging) from antagonists. Like animals, plants also use camouflage as a defence against herbivores. However, this can potentially reduce their attractiveness to pollinators. METHODS: Using Fritillaria delavayi, an alpine camouflaged plant with inter-population floral colour divergence, we tested the influence of floral trait differences on reproduction. We conducted pollination experiments, measured floral morphological characteristics, estimated floral colours perceived by pollinators, analysed floral scent and investigated reproductive success in five populations. KEY RESULTS: We found that the reproduction of F. delavayi depends on pollinators. Under natural conditions, a flower-camouflaged population had 100 % fruit set and similar seed set to three out of four yellow-flowered populations. Bumblebees are important pollinators in the visually conspicuous yellow-flowered populations, whereas flies are the only pollinator in the flower-camouflaged population, visiting flowers more frequently than bumblebees. The camouflaged flowers cannot be discriminated from the rock background as perceived by pollinators, but may be located by flies through olfactory cues. CONCLUSIONS: Collectively, our results demonstrate that the flower-camouflaged population has different reproductive traits from the visually conspicuous yellow-flowered populations. A pollinator shift from bumblebees to flies, combined with high visitation frequency, compensates for the attractiveness disadvantage in camouflaged plants.


Assuntos
Flores , Fritillaria , Polinização , Reprodução , Polinização/fisiologia , Animais , Flores/fisiologia , Flores/anatomia & histologia , Reprodução/fisiologia , Abelhas/fisiologia , Fritillaria/fisiologia , Dípteros/fisiologia , Cor , Frutas/fisiologia , Mimetismo Biológico/fisiologia , Pigmentação/fisiologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-38573102

RESUMO

A novel Gram-positive strain, B1T, was isolated from uranium-contaminated soil. The strain was aerobic, rod-shaped, spore-forming, and motile. The strain was able to grow at 20-45 °C, at pH 6.0-9.0, and in the presence of 0-3 % (w/v) NaCl. The complete genome size of the novel strain was 3 853 322 bp. The genomic DNA G+C content was 45.5 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain B1T has the highest similarity to Aneurinibacillus soli CB4T (96. 71 %). However, the novel strain showed an average nucleotide identity value of 89.02 % and a digital DNA-DNA hybridization value of 37.40 % with strain CB4T based on the genome sequences. The major fatty acids were iso-C15 : 0 and C16 : 0. The predominate respiratory quinone was MK7. Diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipids, an unidentified aminolipid and an unidentified lipid were identified as the major polar lipids. The phylogenetic, phenotypic, and chemotaxonomic analyses showed that strain B1T represents a novel species of the genus Aneurinibacillus, for which the name Aneurinibacillus uraniidurans sp. nov. is proposed. The type strain is B1T (=GDMCC 1.4080T=JCM 36228T). Experiments have shown that strain B1T demonstrates uranium tolerance.


Assuntos
Ácidos Graxos , Urânio , Composição de Bases , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias , Solo
16.
Analyst ; 149(13): 3547-3554, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38767669

RESUMO

A novel nanocomposite, [Eu(BTD)3(DPBT)]-BSA@MnO2, is reported to serve as an effective nanoprobe for bimodal time-gated luminescence (TGL) and magnetic resonance (MR) imaging of H2O2in vitro and in vivo. The nanoprobe was fabricated by immobilizing visible-light-excitable Eu3+ complexes in bovine serum albumin (BSA)-coated lamellar MnO2 nanosheets. The TGL of the Eu3+ complex was effectively quenched by the MnO2 nanosheets. Upon exposure to H2O2, the MnO2 nanosheets underwent reduction to Mn2+, which simultaneously triggered rapid, selective and sensitive "turn-on" responses toward H2O2 in both TGL and MR detection modes. The presence of a protective "corona" formed by BSA enables the nanoprobe to withstand high concentrations of glutathione (GSH), a strong reducing agent of MnO2 nanosheets. This capability allows the nanoprobe to be utilized for detecting H2O2 in living biosamples. The combined utilization of TGL and MR detection modes enables the nanoprobe to image H2O2 across a wide range of resolutions, from the subcellular level to the whole body, without any depth limitations. The results obtained from these modes can be cross-validated, enhancing the accuracy of the detection. The capability of the nanoprobe was validated by TGL imaging of endogenous and exogenous H2O2 in live HeLa cells, as well as bimodal TGL-MR imaging of H2O2 in tumor-bearing mice. The research achievements suggest that the integration of luminescent lanthanide complexes with protein-coated MnO2 nanosheets offers a promising bimodal TGL-MR sensing platform for H2O2in vitro and in vivo.


Assuntos
Európio , Peróxido de Hidrogênio , Imageamento por Ressonância Magnética , Compostos de Manganês , Óxidos , Soroalbumina Bovina , Peróxido de Hidrogênio/química , Soroalbumina Bovina/química , Európio/química , Compostos de Manganês/química , Animais , Óxidos/química , Imageamento por Ressonância Magnética/métodos , Humanos , Camundongos , Células HeLa , Medições Luminescentes/métodos , Nanoestruturas/química , Bovinos , Luminescência , Nanocompostos/química , Complexos de Coordenação/química , Limite de Detecção
17.
Inorg Chem ; 63(29): 13244-13252, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38981109

RESUMO

As a crucial biological gasotransmitter, hydrogen sulfide (H2S) plays important roles in many pathological and physiological processes. Highly selective and sensitive detection of H2S is significant for the precise diagnosis and evaluation of diverse diseases. Nevertheless, challenges remain in view of the interference of autofluorescence in organisms and the stronger reactivity of H2S itself. Herein, we report the design and synthesis of a novel H2S-responsive ß-diketonate-europium(III) complex-based probe, [Eu(DNB-Npketo)3(terpy)], for background-free time-gated luminescence (TGL) detection and imaging of H2S in autofluorescence-rich biological samples. The probe, consisting of a 2,4-dinitrobenzenesulfonyl (DNB) group coupled to a ß-diketonate-europium(III) complex, shows almost no luminescence owing to the existence of intramolecular photoinduced electron transfer. The cleavage of the DNB group by a H2S-triggered reaction results in the recovery of the long-lived luminescence of the Eu3+ complex, allowing the detection of H2S in complicated biological samples to be performed in TGL mode. The probe showed a fast response, high specificity, and high sensitivity toward H2S, which enabled it to be successfully used for the quantitative TGL detection of H2S in tissue homogenates of mouse organs. Additionally, the low cytotoxicity of the probe allowed it to be further used for the TGL imaging of H2S in living cells and mice under different stimuli. All of the results suggested the potential of the probe for the investigation and diagnosis of H2S-related diseases.


Assuntos
Complexos de Coordenação , Európio , Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/análise , Animais , Camundongos , Humanos , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Európio/química , Medições Luminescentes , Imagem Óptica , Estrutura Molecular , Luminescência , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Cetoácidos/química
18.
Inorg Chem ; 63(22): 10443-10451, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38774973

RESUMO

Long-term in situ plasma membrane-targeted imaging is highly significant for investigating specific biological processes and functions, especially for the imaging and tracking of apoptosis processes of cells. However, currently developed membrane probes are rarely utilized to monitor the in situ damage of the plasma membrane. Herein, a transition-metal complex phosphorescent indicator, Ru-Chol, effectively paired with cholesterol, exhibits excellent properties on staining the plasma membrane, with excellent antipermeability, good photostability, large Stokes shift, and long luminescence lifetime. In addition, Ru-Chol not only has the potential to differentiate cancerous cells from normal cells but also tracks in real time the entire progression of cisplatin-induced plasma membrane damage and cell apoptosis. Therefore, Ru-Chol can serve as an efficient tool for the monitoring of morphological and physiological changes in the plasma membrane, providing assistance for drug screening and early diagnosis and treatment of diseases, such as immunodeficiency, diabetes, cirrhosis, and tumors.


Assuntos
Membrana Celular , Colesterol , Complexos de Coordenação , Rutênio , Humanos , Rutênio/química , Colesterol/química , Colesterol/análise , Membrana Celular/química , Membrana Celular/metabolismo , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Apoptose/efeitos dos fármacos , Substâncias Luminescentes/química , Substâncias Luminescentes/síntese química , Cisplatino/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Estrutura Molecular
19.
Methods ; 217: 10-17, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37348825

RESUMO

Ratiometric luminescence probes have attracted widespread attention because of their self-calibration capability. However, some defects, such as small emission shift, severe spectral overlap and poor water solubility, limit their application in the field of biological imaging. In this study, a unique luminescence probe, Ru-COU, has been developed by combining tris(bipyridine)ruthenium(II) complex with coumarin derivative through a formaldehyde-responsive linker. The probe exhibited a large emission shift (Δλ > 100 nm) and good water solubility, achieving ratiometric emission responses at 505 nm and 610 nm toward formaldehyde under acidic conditions. Besides, ratiometric luminescence imaging of formaldehyde in living cells and Alzheimer disease mouse's brain slices demonstrates the potential value of Ru-COU for the diagnosis and treatment of formaldehyde related diseases.


Assuntos
Luminescência , Rutênio , Animais , Camundongos , Cumarínicos , Corantes Fluorescentes , Formaldeído , Células HeLa , Medições Luminescentes , Lisossomos , Água
20.
Acta Pharmacol Sin ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103530

RESUMO

Targeted protein degradation technology has gained substantial momentum over the past two decades as a revolutionary strategy for eliminating pathogenic proteins that are otherwise refractory to treatment. Among the various approaches developed to harness the body's innate protein homeostasis mechanisms for this purpose, lysosome targeting chimeras (LYTACs) that exploit the lysosomal degradation pathway by coupling the target proteins with lysosome-trafficking receptors represent the latest innovation. These chimeras are uniquely tailored to degrade proteins that are membrane-bound and extracellular, encompassing approximately 40% of all proteome. Several novel LYTAC formulas have been developed recently, providing valuable insights for the design and development of therapeutic degraders. This review delineates the recent progresses of LYTAC technology, its practical applications, and the factors that dictate target degradation efficiency. The potential and emerging trends of this technology are discussed as well. LYTAC technology offers a promising avenue for targeted protein degradation, potentially revolutionizing the therapeutic landscape for numerous diseases.

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