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1.
Cell ; 184(22): 5541-5558.e22, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34644528

RESUMO

Retrotransposons mediate gene regulation in important developmental and pathological processes. Here, we characterized the transient retrotransposon induction during preimplantation development of eight mammals. Induced retrotransposons exhibit similar preimplantation profiles across species, conferring gene regulatory activities, particularly through long terminal repeat (LTR) retrotransposon promoters. A mouse-specific MT2B2 retrotransposon promoter generates an N-terminally truncated Cdk2ap1ΔN that peaks in preimplantation embryos and promotes proliferation. In contrast, the canonical Cdk2ap1 peaks in mid-gestation and represses cell proliferation. This MT2B2 promoter, whose deletion abolishes Cdk2ap1ΔN production, reduces cell proliferation and impairs embryo implantation, is developmentally essential. Intriguingly, Cdk2ap1ΔN is evolutionarily conserved in sequence and function yet is driven by different promoters across mammals. The distinct preimplantation Cdk2ap1ΔN expression in each mammalian species correlates with the duration of its preimplantation development. Hence, species-specific transposon promoters can yield evolutionarily conserved, alternative protein isoforms, bestowing them with new functions and species-specific expression to govern essential biological divergence.


Assuntos
Sequência Conservada , Desenvolvimento Embrionário/genética , Proteínas Quinases/metabolismo , Retroelementos/genética , Proteínas Supressoras de Tumor/metabolismo , Animais , Sequência de Bases , Blastocisto/metabolismo , Proliferação de Células , Evolução Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Mamíferos/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Regiões Promotoras Genéticas , Isoformas de Proteínas/metabolismo
2.
Genes Dev ; 35(15-16): 1109-1122, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34301766

RESUMO

Lung adenocarcinoma, the most prevalent lung cancer subtype, is characterized by its high propensity to metastasize. Despite the importance of metastasis in lung cancer mortality, its underlying cellular and molecular mechanisms remain largely elusive. Here, we identified miR-200 miRNAs as potent suppressors for lung adenocarcinoma metastasis. miR-200 expression is specifically repressed in mouse metastatic lung adenocarcinomas, and miR-200 decrease strongly correlates with poor patient survival. Consistently, deletion of mir-200c/141 in the KrasLSL-G12D/+ ; Trp53flox/flox lung adenocarcinoma mouse model significantly promoted metastasis, generating a desmoplastic tumor stroma highly reminiscent of metastatic human lung cancer. miR-200 deficiency in lung cancer cells promotes the proliferation and activation of adjacent cancer-associated fibroblasts (CAFs), which in turn elevates the metastatic potential of cancer cells. miR-200 regulates the functional interaction between cancer cells and CAFs, at least in part, by targeting Notch ligand Jagged1 and Jagged2 in cancer cells and inducing Notch activation in adjacent CAFs. Hence, the interaction between cancer cells and CAFs constitutes an essential mechanism to promote metastatic potential.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pulmonares , MicroRNAs , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica/patologia
3.
Nucleic Acids Res ; 51(20): e105, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37843111

RESUMO

Cytosine base editors (CBEs), which enable precise C-to-T substitutions, have been restricted by potential safety risks, including DNA off-target edits, RNA off-target edits and additional genotoxicity such as DNA damages induced by double-strand breaks (DSBs). Though DNA and RNA off-target edits have been ameliorated via various strategies, evaluation and minimization of DSB-associated DNA damage risks for most CBEs remain to be resolved. Here we demonstrate that YE1, an engineered CBE variant with minimized DNA and RNA off-target edits, could induce prominent DSB-associated DNA damage risks, manifested as γH2AX accumulation in human cells. We then perform deaminase engineering for two deaminases lamprey LjCDA1 and human APOBEC3A, and generate divergent CBE variants with eliminated DSB-associated DNA damage risks, in addition to minimized DNA/RNA off-target edits. Furthermore, the editing scopes and sequence preferences of APOBEC3A-derived CBEs could be further diversified by internal fusion strategy. Taken together, this study provides updated evaluation platform for DSB-associated DNA damage risks of CBEs and further generates a series of safer toolkits with diversified editing signatures to expand their applications.


Assuntos
Citosina , Edição de Genes , Humanos , RNA/genética , Dano ao DNA , DNA/genética , Sistemas CRISPR-Cas
4.
J Chem Phys ; 160(21)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38828807

RESUMO

In this paper, we introduce the Floquet mean-field dynamics and Floquet surface hopping approaches to study the nonadiabatic dynamics in periodically driven solid systems. We demonstrate that these two approaches can be formulated in both real and reciprocal spaces. Using the two approaches, we are able to simulate the interaction between electronic carriers and phonons under periodic drivings, such as strong light-matter interactions. Employing the Holstein and Peierls models, we show that strong light-matter interactions can effectively modulate the dynamics of electronic population and mobility. Notably, our study demonstrates the feasibility and effectiveness of modeling low-momentum carriers' interactions with phonons using a truncated reciprocal space basis, an approach impractical in real space frameworks. Moreover, we reveal that even with a significant truncation, carrier populations derived from surface hopping maintain greater accuracy compared to those obtained via mean-field dynamics. These results underscore the potential of our proposed methods in advancing the understanding of carrier-phonon interactions in various periodically driven materials.

5.
BMC Pregnancy Childbirth ; 24(1): 114, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321376

RESUMO

BACKGROUND: Folic acid supplementation is recommended for reducing the risk of birth defects. We aimed to assess the protective association of periconception folic acid supplements with birth defects in real-world setting. METHODS: This prospective, population-based cohort study utilized national preconception registered data of married Chinese couples planning a pregnancy within 6 months between 2010 and 2012 in Mainland China. Participated women are freely provided folic acid starting 3 months before conception till 3 months after conception. Birth defects were self-reported at 42 days postpartumn followup. R software (v4.0.2) was applied for statistical analyses. RESULTS: Complete data of 567,547 couples with pregnancy outcomes and folic acid supplementation were extracted for final analysis. A total of 74.7% women were with folic acid supplementation, and 599 birth defects were self-reported. The odd of birth defects was lower among women taking folic acid compared to their counterparts not taking (0.102% vs 0.116%, P < 0.001). In the multiple logistic regression analyses, the odd of birth defects was lower among couples with maternal folic acid supplementation (OR = 0.78, 95%CI: 0.66-0.95, P = 0.011), especially decreased odd of neural tube defects (NTDs) (OR = 0.56, 95%CI: 0.39-0.82, P = 0.003). This association was confirmed by 1:4 and 1:10 case control analysis. Odds of birth defects were significantly lower among women with folic acid supplementation more than 3 months before pregnancy (P < 0.001), and moreover, the odds of cleft (P = 0.007) and NTDs (P = 0.007) were of notable decrease. CONCLUSION: This retrospective case cohort study provides programmatic evidence for public health strategy-making to for reducing the risk of NTDs and clefts.


Assuntos
Ácido Fólico , Defeitos do Tubo Neural , Gravidez , Feminino , Humanos , Masculino , Estudos de Coortes , Estudos Prospectivos , Estudos Retrospectivos , Defeitos do Tubo Neural/prevenção & controle , Suplementos Nutricionais , China
6.
Brief Bioinform ; 22(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-33230537

RESUMO

MOTIVATION: Annotating genetic variants from summary statistics of genome-wide association studies (GWAS) is crucial for predicting risk genes of various disorders. The multimarker analysis of genomic annotation (MAGMA) is one of the most popular tools for this purpose, where MAGMA aggregates signals of single nucleotide polymorphisms (SNPs) to their nearby genes. In biology, SNPs may also affect genes that are far away in the genome, thus missed by MAGMA. Although different upgrades of MAGMA have been proposed to extend gene-wise variant annotations with more information (e.g. Hi-C or eQTL), the regulatory relationships among genes and the tissue specificity of signals have not been taken into account. RESULTS: We propose a new approach, namely network-enhanced MAGMA (nMAGMA), for gene-wise annotation of variants from GWAS summary statistics. Compared with MAGMA and H-MAGMA, nMAGMA significantly extends the lists of genes that can be annotated to SNPs by integrating local signals, long-range regulation signals (i.e. interactions between distal DNA elements), and tissue-specific gene networks. When applied to schizophrenia (SCZ), nMAGMA is able to detect more risk genes (217% more than MAGMA and 57% more than H-MAGMA) that are involved in SCZ compared with MAGMA and H-MAGMA, and more of nMAGMA results can be validated with known SCZ risk genes. Some disease-related functions (e.g. the ATPase pathway in Cortex) are also uncovered in nMAGMA but not in MAGMA or H-MAGMA. Moreover, nMAGMA provides tissue-specific risk signals, which are useful for understanding disorders with multitissue origins.


Assuntos
Redes Reguladoras de Genes , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Esquizofrenia/genética , Software , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino
7.
Brief Bioinform ; 22(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-33367491

RESUMO

The human cerebral cortex undergoes profound structural and functional dynamic variations across the lifespan, whereas the underlying molecular mechanisms remain unclear. Here, with a novel method transcriptome-connectome correlation analysis (TCA), which integrates the brain functional magnetic resonance images and region-specific transcriptomes, we identify age-specific cortex (ASC) gene signatures for adolescence, early adulthood and late adulthood. The ASC gene signatures are significantly correlated with the cortical thickness (P-value <2.00e-3) and myelination (P-value <1.00e-3), two key brain structural features that vary in accordance with brain development. In addition to the molecular underpinning of age-related brain functions, the ASC gene signatures allow delineation of the molecular mechanisms of neuropsychiatric disorders, such as the regulation between ARNT2 and its target gene ETF1 involved in Schizophrenia. We further validate the ASC gene signatures with published gene sets associated with the adult cortex, and confirm the robustness of TCA on other brain image datasets. Availability: All scripts are written in R. Scripts for the TCA method and related statistics result can be freely accessed at https://github.com/Soulnature/TCA. Additional data related to this paper may be requested from the authors.


Assuntos
Envelhecimento/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Córtex Cerebral/metabolismo , Fatores de Terminação de Peptídeos/biossíntese , Esquizofrenia/metabolismo , Transcriptoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Cancer Cell Int ; 23(1): 26, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788565

RESUMO

BACKGROUND: Mounting evidence supports that matrix metalloproteinase (MMPs) are highly associated with tumor progression and that targeting MMPs may overcome the barrier of immune suppression. Among these, whether MMP2 functions as an immunosuppressive role in melanoma, remains unclear. METHODS: The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interactive Analysis 2 (GEPIA2) databases were used to assess the prognosis of MMP2 in melanoma, after which Tumor immune estimation resource (TIMER) was used to explore the relationship between MMP2 expression and cancer associated fibroblasts (CAFs) infiltration. Finally, we evaluated the efficacy of MMP2 inhibitor on CAFs infiltration and immunotherapy using a mouse melanoma model. RESULTS: In general, the expression of MMP2, MMP13, MMP16, MMP17 and MMP25 were significantly associated with skin cutaneous melanoma (SKCM) patients prognosis, among which MMP2 low expression benefited patients the most. Especially, the overall survival (OS) of BRAF mutation patients with high MMP2 expression was significantly lower than the MMP2 low expression group, but there was no significant difference in BRAF wild-type patients. KEGG and GO enrichment analysis indicated that MMP2 related genes were mostly associated with extracellular structure organization, collagen-containing extracellular matrix and extracellular matrix structural constituent. Furthermore, in almost all cancers, MMP2 expression was positively correlated with CAFs infiltration. MMP2 inhibitor works synergistically with PD-1 antibody and induces tumor regression in a mouse melanoma model, which is dependent on decreased CAFs infiltration. CONCLUSIONS: This suggests that MMP2 plays a vital role in the regulation of CAFs infiltration, potentially participating in immunotherapy response, and thus representing a valuable target of immunotherapy in melanoma.

9.
Mol Psychiatry ; 27(6): 2720-2730, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35379909

RESUMO

Neurological and psychiatric disorders have overlapped phenotypic profiles, but the underlying tissue-specific functional processes remain largely unknown. In this study, we explore the shared tissue-specificity among 14 neuropsychiatric disorders through the disrupted long-range gene regulations by GWAS-identified regulatory SNPs. Through Hi-C interactions, averagely 38.0% and 17.2% of the intergenic regulatory SNPs can be linked to target protein-coding genes in brain and non-brain tissues, respectively. Interestingly, while the regulatory target genes in the brain tend to enrich in nervous system development related processes, those in the non-brain tissues are inclined to interfere with synapse and neuroinflammation related processes. Compared to psychiatric disorders, neurological disorders present more prominently the neuroinflammatory processes in both brain and non-brain tissues, indicating an intrinsic difference in mechanisms. Through tissue-specific gene regulatory networks, we then constructed disorder similarity networks in two brain and three non-brain tissues, highlighting both known disorder clusters (e.g. the neurodevelopmental disorders) and unexpected disorder clusters (e.g. Parkinson's disease is consistently grouped with psychiatric disorders). We showcase the potential pharmaceutical applications of the small bowel and its disorder clusters, illustrated by the known drug targets NR1I3 and NFACT1, and their small bowel-specific regulatory modules. In conclusion, disrupted long-range gene regulations in both brain and non-brain tissues contribute to the similarity among distinct clusters of neuropsychiatric disorders, and the tissue-specifically shared functions and regulators for disease clusters may provide insights for future therapeutic investigations.


Assuntos
Redes Reguladoras de Genes , Transtornos do Neurodesenvolvimento , Encéfalo , Regulação da Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , Transtornos do Neurodesenvolvimento/genética , Polimorfismo de Nucleotídeo Único
10.
J Nanobiotechnology ; 21(1): 255, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542245

RESUMO

The COVID-19 pandemic, which originated in Hubei, China, in December 2019, has had a profound impact on global public health. With the elucidation of the SARS-CoV-2 virus structure, genome type, and routes of infection, a variety of diagnostic methods have been developed for COVID-19 detection and surveillance. Although the pandemic has been declared over, we are still significantly affected by it in our daily lives in the post-pandemic era. Among the various diagnostic methods, nanomaterials, especially metallic nanomaterials, have shown great potential in the field of bioanalysis due to their unique physical and chemical properties. This review highlights the important role of metallic nanosensors in achieving accurate and efficient detection of COVID-19 during the pandemic outbreak and spread. The sensing mechanisms of each diagnostic device capable of analyzing a range of targets, including viral nucleic acids and various proteins, are described. Since SARS-CoV-2 is constantly mutating, strategies for dealing with new variants are also suggested. In addition, we discuss the analytical tools needed to detect SARS-CoV-2 variants in the current post-pandemic era, with a focus on achieving rapid and accurate detection. Finally, we address the challenges and future directions of metallic nanomaterial-based COVID-19 detection, which may inspire researchers to develop advanced biosensors for COVID-19 monitoring and rapid response to other virus-induced pandemics based on our current achievements.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Teste para COVID-19
11.
J Nanobiotechnology ; 21(1): 415, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946192

RESUMO

Nucleic acid aptamer-based nanomicelles have great potential for nanomedicine and nanotechnology applications. However, amphiphilic aptamer micelles are known to be inherently unstable upon interaction with cell membranes in the physiological environment, thus potentially compromising their specific targeting against cancer cells. This flaw is addressed in the present work which reports a superstable micellar nanodelivery system as an amphiphilic copolymer self-assembled micelle composed of nucleic acid aptamer and polyvalent hydrophobic poly(maleic anhydride-alt-1-octadecene) (C18PMH). Using Ce6 as a drug model, these C18-aptamer micelles exhibit efficient tumor-targeting and -binding ability, facilitating the entry of Ce6 into targeted cells for photodynamic therapy. In addition, they can be loaded with other hydrophobic drugs and still demonstrate favorable therapeutic effects. As such, these C18-aptamer micelles can serve as a universal platform for loading multiple drugs, providing a safer and more effective solution for treating cancer.


Assuntos
Neoplasias , Ácidos Nucleicos , Humanos , Micelas , Sistemas de Liberação de Medicamentos , Polímeros/química , Neoplasias/tratamento farmacológico , Oligonucleotídeos/uso terapêutico , Ácidos Nucleicos/uso terapêutico , Portadores de Fármacos/química , Linhagem Celular Tumoral
12.
Nano Lett ; 22(7): 2826-2834, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35344667

RESUMO

Metal "X" Frameworks (MXFs) constructed from metal ions and biomacromolecules ("X components") via coordination interactions show crystalline structures and diverse functionalities. Here, a series of MXFs composed of various metal ions (e.g., Zn2+, Hf4+, Ca2+) and DNA oligodeoxynucleotides were reported. With MXF consisting of Hf4+ and CpG oligodeoxynucleotides as the example, we show that such Hf-CpG MXF can achieve high-Z elements-enhanced photon radiotherapy and further trigger robust tumor-specific immune responses, thus showing efficient tumor suppression ability. In vivo experiments showed that external beam radiotherapy applied on tumors locally injected with Hf-CpG MXF result in the thorough elimination of primary tumors, complete inhibition of tumor metastasis, and protection against tumor rechallenge by triggering robust antitumor immune responses. Our findings provide a blueprint for fabricating a variety of rationally designed MXFs with desired functions and present the strategy of stimulating whole-body systemic immune responses by only local treatment of radiotherapy.


Assuntos
Imunoterapia , Neoplasias , DNA , Humanos , Imunidade , Neoplasias/terapia , Oligodesoxirribonucleotídeos/farmacologia
13.
Angew Chem Int Ed Engl ; 62(50): e202307020, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37920913

RESUMO

Chemo-dynamic therapy (CDT) based on the Fenton or Fenton-like reaction has emerged as a promising approach for cancer treatment. However, autophagy-mediated self-protection mechanisms of cancer cells pose a significant challenge to the efficacy of CDT. Herein, we developed metal-DNA nanocomplexes (DACs-Mn) to enhance CDT via DNAzyme inhibition of autophagy. Specifically, Mn-based catalyst in DACs-Mn was used to generate highly hydroxyl radicals (⋅OH) that kill cancer cells, while the ATG5 DNAzyme incorporated into DACs-Mn inhibited the expression of autophagy-associated proteins, thereby improving the efficacy of CDT. By disrupting the self-protective pathway of cells under severe oxidative stress, this novel approach of DACs-Mn was found to synergistically enhance CDT in both in vitro and in vivo models, effectively amplifying tumor-specific oxidative damage. Notably, the Metal-DNA nanocomplexes can also induce immunogenic cell death (ICD), thereby inhibiting tumor metastasis. Specifically, in a bilateral tumor model in mice, the combined approach of CDT and autophagy inhibition followed by immune checkpoint blockade therapy shown significant potential as a novel and effective treatment modality for primary and metastatic tumors.


Assuntos
DNA Catalítico , Nanopartículas , Neoplasias , Animais , Camundongos , Linhagem Celular Tumoral , Neoplasias/patologia , Metais , Radical Hidroxila/metabolismo , Autofagia , Peróxido de Hidrogênio/metabolismo , Microambiente Tumoral
14.
Appl Environ Microbiol ; 88(2): e0161821, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-34788067

RESUMO

Lanthipeptides belong to a family of ribosomally synthesized and posttranslationally modified peptides (RiPPs) containing (methyl)lanthionine residues. Commonly, class I lanthipeptides are synthesized by a gene cluster encoding a precursor peptide (LanA), biosynthetic machinery (LanBTC), a protease (LanP), a two-component regulatory system (LanRK), and an immunity system (LanI and LanFEG). Although nisin and subtilin are highly similar class I lanthipeptides, the cross-regulation by LanRK and the cross-immunity by LanI and LanFEG between the nisin and subtilin systems have been proven to be very low. Here, the possibility of the cross-functionality of LanBTC to modify and transport nisin precursor (NisA) and subtilin precursor (SpaS) was evaluated in Bacillus subtilis and Lactococcus lactis. Interestingly, we found that a promiscuous NisBC-SpaT complex is able to synthesize and export nisin precursor, as efficiently as the native nisin biosynthetic machinery NisBTC, in L. lactis but not B. subtilis. The assembly of the NisBC-SpaT complex at a single microdomain, close to the old cell pole, was observed by fluorescence microscopy in L. lactis. In contrast, such a complex was not formed in B. subtilis. Furthermore, the isolation of the NisBC-SpaT complex and its subcomplexes from the cytoplasmic membrane of L. lactis by pulldown assays was successfully conducted. Our work demonstrates that the association of LanBC with LanT is critical for the efficient biosynthesis and secretion of the lanthipeptide precursor with complete modifications and suggests a cooperative mechanism between LanBC and LanT in the modification and transport processes. IMPORTANCE A multimeric synthetase LanBTC complex has been proposed for the in vivo production of class I lanthipeptides. However, it has been demonstrated that LanB, LanC, and LanT can perform their functionality in vivo and in vitro, independently of other Lan proteins. The role of protein-protein interactions, especially between the modification complex LanBC and the transport system LanT, in the biosynthesis process of lanthipeptides is still unclear. In this study, the importance of the presence of a well-installed LanBTC complex in the cell membrane for lanthipeptide biosynthesis and transport was reinforced. In L. lactis, the recruitment of SpaT from the peripheral cell membrane to the cell poles by the NisBC complex was observed, which may explain the mechanism by which the secretion of the premature peptide is prevented.


Assuntos
Lactococcus lactis , Nisina , Bacillus subtilis/genética , Proteínas de Bactérias/metabolismo , Transporte Biológico , Lactococcus lactis/metabolismo , Ligases/metabolismo , Nisina/metabolismo
15.
Chemistry ; 28(68): e202202589, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36063109

RESUMO

An innovative strategy for circularly polarized luminescence (CPL) of carbon dots (CDs) has been developed: The achiral CDs displayed contrary supramolecular chirality and opposite CPL in two different bi-solvent systems, which are due to the formation of self-assembled helical nanostructures with two diverse assembly modes (P and M) in aggregate state via intermolecular π-π interactions and differential hydrogen bonding (H-bonding) without the need of any additional element of chirality.


Assuntos
Carbono , Nanoestruturas , Solventes , Luminescência , Ligação de Hidrogênio
16.
Soft Matter ; 18(16): 3125-3129, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35411907

RESUMO

A novel helix hydrogel with a G-quartet structure was synthesized from guanosine (Gua) and its derivative 5'-guanosine monophosphate (5'-GMP) under a molecular crowding environment. The chirality of the hydrogel is adjusted by controlling the gelling speed. The chiral hydrogel can induce an achiral dye Thioflavin T (ThT) to realize circularly polarized fluorescence (CPL). The CPL dissymmetry factor |glum| of the dye-hydrogels can reach 3 × 10-2 and can be switched easily.


Assuntos
Hidrogéis , Luminescência , Fluorescência
17.
Entropy (Basel) ; 24(2)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35205445

RESUMO

In the era of the interconnection of all things, the security of the Internet of Things (IoT) has become a new challenge. The theoretical basis of unconditional security can be guaranteed by using quantum keys, which can form a QKD network-based security protection system of quantum Internet of Things (Q-IoT). However, due to the low generation rate of the quantum keys, the lack of a reasonable key allocation scheme can reduce the overall service quality. Therefore, this paper proposes a dynamic on-demand key allocation scheme, named DDKA-QKDN, to better meet the requirements of lightweight in the application scenario of Q-IoT and make efficient use of quantum key resources. Taking the two processes of the quantum key pool (QKP) key allocation and the QKP key supplement into account, the scheme dynamically allocates quantum keys and supplements the QKP on demand, which quantitatively weighs the quantum key quantity and security requirements of key requests in proportion. The simulation results show that the system efficiency and the ability of QKP to provide key request services are significantly improved by this scheme.

18.
Angew Chem Int Ed Engl ; 61(47): e202211822, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36070976

RESUMO

Chiral materials related to circularly polarized luminescence (CPL) make up a rapidly developing new field that has broad application prospects in optoelectronic devices, selective recognition, biomedicine, and other fields. Biofunctional chiral materials are also attracting increasing attention because of their unique biocompatibility, chiral recognition, and coding. However, there has been little discussion on biomolecule-based CPL till now. In this Review, the latest progress in CPL materials related with biomolecules are reviewed, including the chiral construction from molecular level to giant microstructure, as well as their emerging applications. In addition, we discuss the challenges and prospects of bio-based CPL materials, hoping this work will provide new perspectives and insights for more related research.


Assuntos
Luminescência , Medições Luminescentes , Estereoisomerismo
19.
J Org Chem ; 86(1): 1292-1299, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33350303

RESUMO

A visible-light-driven protocol for the synthesis of aryl trifluoromethyl thioethers under photocatalyst- and metal-free conditions has been pursued. The procedure exploits the peculiar properties of arylazo sulfones (having electron-rich or electron-poor substituents on the (hetero)aromatic ring) as photochemical precursors of aryl radicals and S-trifluoromethyl arylsulfonothioates as easy-to-handle trifluoromethylthiolating agents.

20.
Proc Natl Acad Sci U S A ; 115(1): E34-E43, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29255034

RESUMO

To impart biomedical functions to nanoparticles (NPs), the common approach is to conjugate functional groups onto NPs by dint of the functions of those groups per se. It is still beyond current reach to create protein-like specific interactions and functions on NPs by conformational engineering of nonfunctional groups on NPs. Here, we develop a conformational engineering method to create an NP-based artificial antibody, denoted "Goldbody," through conformational reconstruction of the complementary-determining regions (CDRs) of natural antibodies on gold NPs (AuNPs). The seemingly insurmountable task of controlling the conformation of the CDR loops, which are flexible and nonfunctional in the free form, was accomplished unexpectedly in a simple way. Upon anchoring both terminals of the free CDR loops on AuNPs, we managed to reconstruct the "active" conformation of the CDR loops by tuning the span between the two terminals and, as a result, the original specificity was successfully reconstructed on the AuNPs. Two Goldbodies have been created by this strategy to specifically bind with hen egg white lysozyme and epidermal growth factor receptor, with apparent affinities several orders of magnitude stronger than that of the original natural antibodies. Our work demonstrates that it is possible to create protein-like functions on NPs in a protein-like way, namely by tuning flexible surface groups to the correct conformation. Given the apparent merits, including good stability, of Goldbodies, we anticipate that a category of Goldbodies could be created to target different antigens and thus used as substitutes for natural antibodies in various applications.


Assuntos
Anticorpos Monoclonais/química , Regiões Determinantes de Complementaridade/química , Ouro/química , Nanopartículas Metálicas/química , Conformação Proteica
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