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1.
Cell ; 172(4): 650-665, 2018 02 08.
Article in English | MEDLINE | ID: mdl-29425488

ABSTRACT

Transcription factors (TFs) recognize specific DNA sequences to control chromatin and transcription, forming a complex system that guides expression of the genome. Despite keen interest in understanding how TFs control gene expression, it remains challenging to determine how the precise genomic binding sites of TFs are specified and how TF binding ultimately relates to regulation of transcription. This review considers how TFs are identified and functionally characterized, principally through the lens of a catalog of over 1,600 likely human TFs and binding motifs for two-thirds of them. Major classes of human TFs differ markedly in their evolutionary trajectories and expression patterns, underscoring distinct functions. TFs likewise underlie many different aspects of human physiology, disease, and variation, highlighting the importance of continued effort to understand TF-mediated gene regulation.


Subject(s)
Evolution, Molecular , Gene Expression Regulation , Response Elements , Transcription Factors , Amino Acid Motifs , Humans , Transcription Factors/chemistry , Transcription Factors/classification , Transcription Factors/genetics , Transcription Factors/metabolism
2.
Nature ; 626(8001): 1005-1010, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38418918

ABSTRACT

Heterogeneous catalysts are widely used to promote chemical reactions. Although it is known that chemical reactions usually happen on catalyst surfaces, only specific surface sites have high catalytic activity. Thus, identifying active sites and maximizing their presence lies at the heart of catalysis research1-4, in which the classic model is to categorize active sites in terms of distinct surface motifs, such as terraces and steps1,5-10. However, such a simple categorization often leads to orders of magnitude errors in catalyst activity predictions and qualitative uncertainties of active sites7,8,11,12, thus limiting opportunities for catalyst design. Here, using stepped Pt(111) surfaces and the electrochemical oxygen reduction reaction (ORR) as examples, we demonstrate that the root cause of larger errors and uncertainties is a simplified categorization that overlooks atomic site-specific reactivity driven by surface stress release. Specifically, surface stress release at steps introduces inhomogeneous strain fields, with up to 5.5% compression, leading to distinct electronic structures and reactivity for terrace atoms with identical local coordination, and resulting in atomic site-specific enhancement of ORR activity. For the terrace atoms flanking both sides of the step edge, the enhancement is up to 50 times higher than that of the atoms in the middle of the terrace, which permits control of ORR reactivity by either varying terrace widths or controlling external stress. Thus, the discovery of the above synergy provides a new perspective for both fundamental understanding of catalytically active atomic sites and design principles of heterogeneous catalysts.

3.
Nat Immunol ; 18(2): 236-245, 2017 02.
Article in English | MEDLINE | ID: mdl-28024152

ABSTRACT

Toll-like receptor (TLR) activation contributes to premalignant hematologic conditions, such as myelodysplastic syndromes (MDS). TRAF6, a TLR effector with ubiquitin (Ub) ligase activity, is overexpressed in MDS hematopoietic stem/progenitor cells (HSPCs). We found that TRAF6 overexpression in mouse HSPC results in impaired hematopoiesis and bone marrow failure. Using a global Ub screen, we identified hnRNPA1, an RNA-binding protein and auxiliary splicing factor, as a substrate of TRAF6. TRAF6 ubiquitination of hnRNPA1 regulated alternative splicing of Arhgap1, which resulted in activation of the GTP-binding Rho family protein Cdc42 and accounted for hematopoietic defects in TRAF6-expressing HSPCs. These results implicate Ub signaling in coordinating RNA processing by TLR pathways during an immune response and in premalignant hematologic diseases, such as MDS.


Subject(s)
Hematopoietic Stem Cells/physiology , Heterogeneous-Nuclear Ribonucleoprotein Group A-B/metabolism , Myelodysplastic Syndromes/immunology , Precancerous Conditions/immunology , Signal Transduction , TNF Receptor-Associated Factor 6/metabolism , Ubiquitination , Animals , Autoimmunity , Cells, Cultured , Hematopoiesis/genetics , Heterogeneous Nuclear Ribonucleoprotein A1 , Heterogeneous-Nuclear Ribonucleoprotein Group A-B/genetics , Immunity, Innate , Mice , Mice, Inbred C57BL , Mice, Transgenic , Signal Transduction/genetics , TNF Receptor-Associated Factor 6/genetics , Toll-Like Receptors/metabolism , Ubiquitination/genetics , cdc42 GTP-Binding Protein/metabolism
4.
Cell ; 158(6): 1431-1443, 2014 Sep 11.
Article in English | MEDLINE | ID: mdl-25215497

ABSTRACT

Transcription factor (TF) DNA sequence preferences direct their regulatory activity, but are currently known for only ∼1% of eukaryotic TFs. Broadly sampling DNA-binding domain (DBD) types from multiple eukaryotic clades, we determined DNA sequence preferences for >1,000 TFs encompassing 54 different DBD classes from 131 diverse eukaryotes. We find that closely related DBDs almost always have very similar DNA sequence preferences, enabling inference of motifs for ∼34% of the ∼170,000 known or predicted eukaryotic TFs. Sequences matching both measured and inferred motifs are enriched in chromatin immunoprecipitation sequencing (ChIP-seq) peaks and upstream of transcription start sites in diverse eukaryotic lineages. SNPs defining expression quantitative trait loci in Arabidopsis promoters are also enriched for predicted TF binding sites. Importantly, our motif "library" can be used to identify specific TFs whose binding may be altered by human disease risk alleles. These data present a powerful resource for mapping transcriptional networks across eukaryotes.


Subject(s)
Arabidopsis/genetics , Nucleotide Motifs , Sequence Analysis, DNA , Transcription Factors/metabolism , Arabidopsis/metabolism , Chromatin Immunoprecipitation , Humans , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Protein Binding , Quantitative Trait Loci
6.
Am J Hum Genet ; 111(2): 280-294, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38183988

ABSTRACT

Eosinophilic esophagitis (EoE) is a rare atopic disorder associated with esophageal dysfunction, including difficulty swallowing, food impaction, and inflammation, that develops in a small subset of people with food allergies. Genome-wide association studies (GWASs) have identified 9 independent EoE risk loci reaching genome-wide significance (p < 5 × 10-8) and 27 additional loci of suggestive significance (5 × 10-8 < p < 1 × 10-5). In the current study, we perform linkage disequilibrium (LD) expansion of these loci to nominate a set of 531 variants that are potentially causal. To systematically interrogate the gene regulatory activity of these variants, we designed a massively parallel reporter assay (MPRA) containing the alleles of each variant within their genomic sequence context cloned into a GFP reporter library. Analysis of reporter gene expression in TE-7, HaCaT, and Jurkat cells revealed cell-type-specific gene regulation. We identify 32 allelic enhancer variants, representing 6 genome-wide significant EoE loci and 7 suggestive EoE loci, that regulate reporter gene expression in a genotype-dependent manner in at least one cellular context. By annotating these variants with expression quantitative trait loci (eQTL) and chromatin looping data in related tissues and cell types, we identify putative target genes affected by genetic variation in individuals with EoE. Transcription factor enrichment analyses reveal possible roles for cell-type-specific regulators, including GATA3. Our approach reduces the large set of EoE-associated variants to a set of 32 with allelic regulatory activity, providing functional insights into the effects of genetic variation in this disease.


Subject(s)
Enteritis , Eosinophilia , Eosinophilic Esophagitis , Gastritis , Humans , Eosinophilic Esophagitis/genetics , Eosinophilic Esophagitis/complications , Genome-Wide Association Study , Genotype , Quantitative Trait Loci/genetics
7.
PLoS Genet ; 18(5): e1009973, 2022 05.
Article in English | MEDLINE | ID: mdl-35576187

ABSTRACT

Atopic dermatitis (AD) is one of the most common skin disorders among children. Disease etiology involves genetic and environmental factors, with 29 independent AD risk loci enriched for risk allele-dependent gene expression in the skin and CD4+ T cell compartments. We investigated the potential epigenetic mechanisms responsible for the genetic susceptibility of CD4+ T cells. To understand the differences in gene regulatory activity in peripheral blood T cells in AD, we measured chromatin accessibility (an assay based on transposase-accessible chromatin sequencing, ATAC-seq), nuclear factor kappa B subunit 1 (NFKB1) binding (chromatin immunoprecipitation with sequencing, ChIP-seq), and gene expression levels (RNA-seq) in stimulated CD4+ T cells from subjects with active moderate-to-severe AD, as well as in age-matched non-allergic controls. Open chromatin regions in stimulated CD4+ T cells were highly enriched for AD genetic risk variants, with almost half of the AD risk loci overlapping AD-dependent ATAC-seq peaks. AD-specific open chromatin regions were strongly enriched for NF-κB DNA-binding motifs. ChIP-seq identified hundreds of NFKB1-occupied genomic loci that were AD- or control-specific. As expected, the AD-specific ChIP-seq peaks were strongly enriched for NF-κB DNA-binding motifs. Surprisingly, control-specific NFKB1 ChIP-seq peaks were not enriched for NFKB1 motifs, but instead contained motifs for other classes of human transcription factors, suggesting a mechanism involving altered indirect NFKB1 binding. Using DNA sequencing data, we identified 63 instances of altered genotype-dependent chromatin accessibility at 36 AD risk variant loci (30% of AD risk loci) that might lead to genotype-dependent gene expression. Based on these findings, we propose that CD4+ T cells respond to stimulation in an AD-specific manner, resulting in disease- and genotype-dependent chromatin accessibility alterations involving NFKB1 binding.


Subject(s)
CD4-Positive T-Lymphocytes , Dermatitis, Atopic , CD4-Positive T-Lymphocytes/metabolism , Child , Chromatin/genetics , DNA , Dermatitis, Atopic/genetics , Epigenesis, Genetic , Humans , NF-kappa B/metabolism
8.
Semin Cancer Biol ; 89: 61-75, 2023 02.
Article in English | MEDLINE | ID: mdl-36682438

ABSTRACT

Over the last decade, the nanomedicine has experienced unprecedented development in diagnosis and management of diseases. A number of nanomedicines have been approved in clinical use, which has demonstrated the potential value of clinical transition of nanotechnology-modified medicines from bench to bedside. The application of artificial intelligence (AI) in development of nanotechnology-based products could transform the healthcare sector by realizing acquisition and analysis of large datasets, and tailoring precision nanomedicines for cancer management. AI-enabled nanotechnology could improve the accuracy of molecular profiling and early diagnosis of patients, and optimize the design pipeline of nanomedicines by tuning the properties of nanomedicines, achieving effective drug synergy, and decreasing the nanotoxicity, thereby, enhancing the targetability, personalized dosing and treatment potency of nanomedicines. Herein, the advances in AI-enabled nanomedicines in cancer management are elaborated and their application in diagnosis, monitoring and therapy as well in precision medicine development is discussed.


Subject(s)
Nanomedicine , Neoplasms , Humans , Artificial Intelligence , Nanotechnology , Drug Delivery Systems , Neoplasms/diagnosis , Neoplasms/drug therapy
9.
BMC Genomics ; 25(1): 273, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38475709

ABSTRACT

BACKGROUND: There are two major genetic types of Epstein-Barr Virus (EBV): type 1 (EBV-1) and type 2 (EBV-2). EBV functions by manipulating gene expression in host B cells, using virus-encoded gene regulatory proteins including Epstein-Barr Nuclear Antigen 2 (EBNA2). While type 1 EBNA2 is known to interact with human transcription factors (hTFs) such as RBPJ, EBF1, and SPI1 (PU.1), type 2 EBNA2 shares only ~ 50% amino acid identity with type 1 and thus may have distinct binding partners, human genome binding locations, and functions. RESULTS: In this study, we examined genome-wide EBNA2 binding in EBV-1 and EBV-2 transformed human B cells to identify shared and unique EBNA2 interactions with the human genome, revealing thousands of type-specific EBNA2 ChIP-seq peaks. Computational predictions based on hTF motifs and subsequent ChIP-seq experiments revealed that both type 1 and 2 EBNA2 co-occupy the genome with SPI1 and AP-1 (BATF and JUNB) hTFs. However, type 1 EBNA2 showed preferential co-occupancy with EBF1, and type 2 EBNA2 preferred RBPJ. These differences in hTF co-occupancy revealed possible mechanisms underlying type-specific gene expression of known EBNA2 human target genes: MYC (shared), CXCR7 (type 1 specific), and CD21 (type 2 specific). Both type 1 and 2 EBNA2 binding events were enriched at systemic lupus erythematosus (SLE) and multiple sclerosis (MS) risk loci, while primary biliary cholangitis (PBC) risk loci were specifically enriched for type 2 peaks. CONCLUSIONS: This study reveals extensive type-specific EBNA2 interactions with the human genome, possible differences in EBNA2 interaction partners, and a possible new role for type 2 EBNA2 in autoimmune disorders. Our results highlight the importance of considering EBV type in the control of human gene expression and disease-related investigations.


Subject(s)
Epstein-Barr Virus Infections , Herpesvirus 4, Human , Humans , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/metabolism , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/metabolism , Genome, Human , Epstein-Barr Virus Nuclear Antigens/genetics , Epstein-Barr Virus Nuclear Antigens/metabolism , Viral Proteins/genetics , Transcription Factors/metabolism
11.
Mol Psychiatry ; 28(3): 1219-1231, 2023 03.
Article in English | MEDLINE | ID: mdl-36604604

ABSTRACT

ATP9A, a lipid flippase of the class II P4-ATPases, is involved in cellular vesicle trafficking. Its homozygous variants are linked to neurodevelopmental disorders in humans. However, its physiological function, the underlying mechanism as well as its pathophysiological relevance in humans and animals are still largely unknown. Here, we report two independent families in which the nonsense mutations c.433C>T/c.658C>T/c.983G>A (p. Arg145*/p. Arg220*/p. Trp328*) in ATP9A (NM_006045.3) cause autosomal recessive hypotonia, intellectual disability (ID) and attention deficit hyperactivity disorder (ADHD). Atp9a null mice show decreased muscle strength, memory deficits and hyperkinetic movement disorder, recapitulating the symptoms observed in patients. Abnormal neurite morphology and impaired synaptic transmission are found in the primary motor cortex and hippocampus of the Atp9a null mice. ATP9A is also required for maintaining neuronal neurite morphology and the viability of neural cells in vitro. It mainly localizes to endosomes and plays a pivotal role in endosomal recycling pathway by modulating small GTPase RAB5 and RAB11 activation. However, ATP9A pathogenic mutants have aberrant subcellular localization and cause abnormal endosomal recycling. These findings provide strong evidence that ATP9A deficiency leads to neurodevelopmental disorders and synaptic dysfunctions in both humans and mice, and establishes novel regulatory roles for ATP9A in RAB5 and RAB11 activity-dependent endosomal recycling pathway and neurological diseases.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Animals , Humans , Mice , Attention Deficit Disorder with Hyperactivity/metabolism , Endosomes/metabolism , Protein Transport , rab5 GTP-Binding Proteins/genetics , rab5 GTP-Binding Proteins/metabolism
12.
PLoS Comput Biol ; 19(1): e1010863, 2023 01.
Article in English | MEDLINE | ID: mdl-36719906

ABSTRACT

Transcription factors read the genome, fundamentally connecting DNA sequence to gene expression across diverse cell types. Determining how, where, and when TFs bind chromatin will advance our understanding of gene regulatory networks and cellular behavior. The 2017 ENCODE-DREAM in vivo Transcription-Factor Binding Site (TFBS) Prediction Challenge highlighted the value of chromatin accessibility data to TFBS prediction, establishing state-of-the-art methods for TFBS prediction from DNase-seq. However, the more recent Assay-for-Transposase-Accessible-Chromatin (ATAC)-seq has surpassed DNase-seq as the most widely-used chromatin accessibility profiling method. Furthermore, ATAC-seq is the only such technique available at single-cell resolution from standard commercial platforms. While ATAC-seq datasets grow exponentially, suboptimal motif scanning is unfortunately the most common method for TFBS prediction from ATAC-seq. To enable community access to state-of-the-art TFBS prediction from ATAC-seq, we (1) curated an extensive benchmark dataset (127 TFs) for ATAC-seq model training and (2) built "maxATAC", a suite of user-friendly, deep neural network models for genome-wide TFBS prediction from ATAC-seq in any cell type. With models available for 127 human TFs, maxATAC is the largest collection of high-performance TFBS prediction models for ATAC-seq. maxATAC performance extends to primary cells and single-cell ATAC-seq, enabling improved TFBS prediction in vivo. We demonstrate maxATAC's capabilities by identifying TFBS associated with allele-dependent chromatin accessibility at atopic dermatitis genetic risk loci.


Subject(s)
Chromatin Immunoprecipitation Sequencing , High-Throughput Nucleotide Sequencing , Nerve Net , Humans , Chromatin/genetics , Deoxyribonucleases/genetics , High-Throughput Nucleotide Sequencing/methods , Sequence Analysis, DNA/methods
13.
Macromol Rapid Commun ; 45(5): e2300559, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38014713

ABSTRACT

Alveolar bone injury under diabetic conditions can severely impede many oral disease treatments. Rebuilding diabetic alveolar bone in clinics is currently challenging due to persistent infection and inflammatory response. Here, an antibacterial DNA-based hydrogel named Agantigel is developed by integrating silver nanoclusters (AgNCs) and tumor necrosis factor-alpha (TNF-α) antibody into DNA hydrogel to promote diabetic alveolar bone regeneration. Agantigel can effectively inhibit bacterial growth through AgNCs while exhibiting negligible cytotoxicity in vitro. The sustained release of TNF-α antibody from Agantigel effectively blocks TNF-α and promotes M2 polarization of macrophages, ultimately accelerating diabetic alveolar bone regeneration in vivo. After 21 days of treatment, Agantigel significantly accelerates the defect healing rate of diabetic alveolar bone up to 82.58 ± 8.58% and improves trabecular architectures compared to free TNF-α (42.52 ± 15.85%). The results imply that DNA hydrogels are potential bio-scaffolds helping the sustained release of multidrug for treating DABI or other oral diseases.


Subject(s)
Diabetes Mellitus , Hydrogels , Humans , Hydrogels/pharmacology , Tumor Necrosis Factor-alpha , Delayed-Action Preparations , Anti-Bacterial Agents/pharmacology , DNA
14.
Article in English | MEDLINE | ID: mdl-38866616

ABSTRACT

BACKGROUND AND AIM: Currently, the relationship between dynamic changes in dietary manganese (Mn) intake and risk of hyperuricemia (HU) is still unclear. This study aimed to identify dietary Mn consumption trajectories in the Chinese adults and assess their relation with the risk of HU. METHODS AND RESULTS: Cohort data from the China Health and Nutrition Survey (CHNS) 1997-2009 were employed in this study. Overall, 6886 adult participants were included. Participants were designated into subgroups based on the trajectories of dietary Mn consumption by sex. Cox proportional hazard models were used to explore the associations between different trajectories and the risk of HU. For men, compared with low stable trajectory group, moderate to high trajectory group was significantly related to reduced risk of HU (HR = 0.61, 95% CI: 0.38 to 0.98) with adjustment for covariates. TC, HDL-C, ApoB, and TG exerted partial regulation function between trajectories and HU. For women, compared with low stable trajectory group, high stable trajectory group was significantly related to reduced risk of HU (HR = 0.76, 95% CI: 0.60 to 0.95) with adjustment for covariates. Similarly, TC, HDL-C, ApoB, and ApoA exerted partial regulation function between trajectories and HU. CONCLUSIONS: Long-term relatively high dietary Mn consumption may have a protective effect against HU in Chinese adults. The differences in HU-related factors among different dietary Mn intake trajectories partially regulated the association between these trajectories and HU.

15.
Nucleic Acids Res ; 50(9): 5313-5334, 2022 05 20.
Article in English | MEDLINE | ID: mdl-35544276

ABSTRACT

Alternative splicing is critical for development; however, its role in the specification of the three embryonic germ layers is poorly understood. By performing RNA-Seq on human embryonic stem cells (hESCs) and derived definitive endoderm, cardiac mesoderm, and ectoderm cell lineages, we detect distinct alternative splicing programs associated with each lineage. The most prominent splicing program differences are observed between definitive endoderm and cardiac mesoderm. Integrative multi-omics analyses link each program with lineage-enriched RNA binding protein regulators, and further suggest a widespread role for Quaking (QKI) in the specification of cardiac mesoderm. Remarkably, knockout of QKI disrupts the cardiac mesoderm-associated alternative splicing program and formation of myocytes. These changes arise in part through reduced expression of BIN1 splice variants linked to cardiac development. Mechanistically, we find that QKI represses inclusion of exon 7 in BIN1 pre-mRNA via an exonic ACUAA motif, and this is concomitant with intron removal and cleavage from chromatin. Collectively, our results uncover alternative splicing programs associated with the three germ lineages and demonstrate an important role for QKI in the formation of cardiac mesoderm.


Subject(s)
Alternative Splicing , Cell Lineage , Germ Layers , RNA-Binding Proteins/metabolism , Cell Differentiation , Endoderm , Heart , Humans , Mesoderm
16.
BMC Pulm Med ; 24(1): 20, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38191360

ABSTRACT

BACKGROUND: Serum tumor markers (STM), extensively used for the diagnosis, monitoring and prognostic assessment of tumors, can be increased in some non-malignant lung diseases. To date, there is a paucity of studies regarding the clinical characteristics of non-cystic fibrosis bronchiectasis patients with positive STMs. OBJECTIVE: To investigate the clinical characteristics and indicators of bronchiectasis with positive STMs. METHODS: The clinical data of 377 bronchiectasis patients was retrospectively collected from January 2017 to December 2019 from Beijing Chaoyang Hospital. Patients were divided into the STM negative group, the single STM positive group and the ≥2 STMs positive group according to the number of the positive STMs. The clinical characteristics are described and compared separately. The multivariate logistic regression analysis model was used to investigate the indicators regarding positive STMs. RESULTS: Patients in the ≥2 STMs positive group were older (P = 0.015), had higher mMRC scores (P < 0.001) and developed higher fever (P = 0.027). Additionally, these patients also had lower Albumin/Globulin Ratio (A/G), albumin (ALB), prealbumin (PAB) (P < 0.001, P < 0.001, P < 0.001, respectively) and higher CRP, ESR and Fbg (P < 0.001, P < 0.001 and P < 0.001, respectively). Age (OR 1.022, 95%CI 1.003-1.042; P = 0.026) and the number of affected lobes (OR 1.443, 95%CI 1.233-1.690; P < 0.001) were independently associated with one and ≥ 2 positive STMs in bronchiectasis patients. CONCLUSION: The ≥2 positive STMs are associated with a higher inflammation status and severer radiologic manifestations in bronchiectasis patients.


Subject(s)
Bronchiectasis , Neoplasms , Humans , Biomarkers, Tumor , Retrospective Studies , Albumins , Bronchiectasis/complications
17.
Mar Drugs ; 22(6)2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38921596

ABSTRACT

Omega-3 fatty acids are in high demand due to their efficacy in treating hypertriglyceridemia and preventing cardiovascular diseases. However, the growth of the industry is hampered by low purity and insufficient productivity. This study aims to develop an efficient RP-MPLC purification method for omega-3 fatty acid ethyl esters with high purity and capacity. The results indicate that the AQ-C18 featuring polar end-capped silanol groups outperformed C18 and others in retention time and impurity separation. By injecting pure fish oil esters with a volume equivalent to a 1.25% bed volume on an AQ-C18 MPLC column using a binary isocratic methanol-water (90:10, v:v) mobile phase at 30 mL/min, optimal omega-3 fatty acid ethyl esters were obtained, with the notable purity of 90.34% and a recovery rate of 74.30%. The total content of EPA and DHA produced increased from 67.91% to 85.27%, meeting the acceptance criteria of no less than 84% set by the 2020 edition of the Pharmacopoeia of the People's Republic of China. In contrast, RP-MPLC significantly enhanced the production efficiency per unit output compared to RP-HPLC. This study demonstrates a pioneering approach to producing omega-3 fatty acid ethyl esters with high purity and of greater quantity using AQ-C18 RP-MPLC, showing this method's significant potential for use in industrial-scale manufacturing.


Subject(s)
Chromatography, Reverse-Phase , Esters , Fatty Acids, Omega-3 , Fish Oils , Fatty Acids, Omega-3/chemistry , Fatty Acids, Omega-3/isolation & purification , Esters/chemistry , Esters/isolation & purification , Fish Oils/chemistry , Chromatography, Reverse-Phase/methods , Chromatography, High Pressure Liquid/methods , Docosahexaenoic Acids/chemistry , Docosahexaenoic Acids/isolation & purification , Eicosapentaenoic Acid/chemistry , Eicosapentaenoic Acid/isolation & purification
18.
Mar Drugs ; 22(2)2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38393061

ABSTRACT

Protein hydrolysates from sea cucumber (Apostichopus japonicus) gonads are rich in active materials with remarkable angiotensin-converting enzyme (ACE) inhibitory activity. Alcalase was used to hydrolyze sea cucumber gonads, and the hydrolysate was separated by the ultrafiltration membrane to produce a low-molecular-weight peptide component (less than 3 kDa) with good ACE inhibitory activity. The peptide component (less than 3 kDa) was isolated and purified using a combination method of ACE gel affinity chromatography and reverse high-performance liquid chromatography. The purified fractions were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the resulting products were filtered using structure-based virtual screening (SBVS) to obtain 20 peptides. Of those, three noncompetitive inhibitory peptides (DDQIHIF with an IC50 value of 333.5 µmol·L-1, HDWWKER with an IC50 value of 583.6 µmol·L-1, and THDWWKER with an IC50 value of 1291.8 µmol·L-1) were further investigated based on their favorable pharmacochemical properties and ACE inhibitory activity. Molecular docking studies indicated that the three peptides were entirely enclosed within the ACE protein cavity, improving the overall stability of the complex through interaction forces with the ACE active site. The total free binding energies (ΔGtotal) for DDQIHIF, HDWWKER, and THDWWKER were -21.9 Kcal·mol-1, -71.6 Kcal·mol-1, and -69.1 Kcal·mol-1, respectively. Furthermore, a short-term assay of antihypertensive activity in spontaneously hypertensive rats (SHRs) revealed that HDWWKER could significantly decrease the systolic blood pressure (SBP) of SHRs after intravenous administration. The results showed that based on the better antihypertensive activity of the peptide in SHRs, the feasibility of targeted affinity purification and computer-aided drug discovery (CADD) for the efficient screening and preparation of ACE inhibitory peptide was verified, which provided a new idea of modern drug development method for clinical use.


Subject(s)
Antihypertensive Agents , Sea Cucumbers , Rats , Animals , Antihypertensive Agents/pharmacology , Angiotensin-Converting Enzyme Inhibitors/chemistry , Chromatography, Liquid , Molecular Docking Simulation , Sea Cucumbers/metabolism , Tandem Mass Spectrometry , Peptides/chemistry , Rats, Inbred SHR , Chromatography, Affinity , Peptidyl-Dipeptidase A/chemistry , Protein Hydrolysates/chemistry , Gonads/metabolism , Angiotensins
19.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Article in English | MEDLINE | ID: mdl-33766917

ABSTRACT

The layered compartmentalization of synaptic connections, a common feature of nervous systems, underlies proper connectivity between neurons and enables parallel processing of neural information. However, the stepwise development of layered neuronal connections is not well understood. The medulla neuropil of the Drosophila visual system, which comprises 10 discrete layers (M1 to M10), where neural computations underlying distinct visual features are processed, serves as a model system for understanding layered synaptic connectivity. The first step in establishing layer-specific connectivity in the outer medulla (M1 to M6) is the innervation by lamina (L) neurons of one of two broad, primordial domains that will subsequently expand and transform into discrete layers. We previously found that the transcription factor dFezf cell-autonomously directs L3 lamina neurons to their proper primordial broad domain before they form synapses within the developing M3 layer. Here, we show that dFezf controls L3 broad domain selection through temporally precise transcriptional repression of the transcription factor slp1 (sloppy paired 1). In wild-type L3 neurons, slp1 is transiently expressed at a low level during broad domain selection. When dFezf is deleted, slp1 expression is up-regulated, and ablation of slp1 fully rescues the defect of broad domain selection in dFezf-null L3 neurons. Although the early, transient expression of slp1 is expendable for broad domain selection, it is surprisingly necessary for the subsequent L3 innervation of the M3 layer. DFezf thus functions as a transcriptional repressor to coordinate the temporal dynamics of a transcriptional cascade that orchestrates sequential steps of layer-specific synapse formation.


Subject(s)
Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/growth & development , Gene Expression Regulation, Developmental , Neurons/physiology , Repressor Proteins/metabolism , Synapses/physiology , Transcription Factors/genetics , Transcription Factors/metabolism , Visual Pathways/growth & development , Animals , Drosophila melanogaster/genetics , Neurons/metabolism , Point Mutation , Repressor Proteins/genetics , Visual Pathways/cytology
20.
Angew Chem Int Ed Engl ; 63(18): e202401331, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38456641

ABSTRACT

A general approach to constructing room temperature phosphorescence (RTP) materials involves the incorporation of a phosphorescent emitter into a rigid host or polymers with high glass transition temperature. However, these materials often suffer from poor processability and suboptimal mechanical properties, limiting their practical applications. In this work, we developed benzothiadiazole-based dialkene (BTD-HEA), a multifunctional phosphorescent emitter with a remarkable yield of intersystem crossing (ΦISC, 99.83 %). Its high triplet exciton generation ability and dialkene structure enable BTD-HEA to act as a photoinitiator and crosslinker, efficiently initiating the polymerization of various monomers within 120 seconds. A range of flexible phosphorescence gels, including hydrogels, organogels, ionogels, and aerogels were fabricated, which exhibit outstanding stretchability and recoverability. Furthermore, the unique fluorescent-phosphorescent colorimetric properties of the gels provide a more sensitive method for the visual determination of the polymerization process. Notably, the phosphorescent emission intensity of the hydrogel can be increased by the formation of ice, allowing for the precise detection of hydrogel freezing. The versatility of this emitter paves the way for fabricating various flexible phosphorescence gels with diverse morphologies using microfluidics, film-shearing, roll coating process, and two/three-dimensional printing, showcasing its potential applications in the fields of bioimaging and bioengineering.

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