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1.
Cell ; 185(8): 1431-1443.e16, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35427499

RESUMO

Synthetic biology has established powerful tools to precisely control cell function. Engineering these systems to meet clinical requirements has enormous medical implications. Here, we adopted a clinically driven design process to build receptors for the autonomous control of therapeutic cells. We examined the function of key domains involved in regulated intramembrane proteolysis and showed that systematic modular engineering can generate a class of receptors that we call synthetic intramembrane proteolysis receptors (SNIPRs) that have tunable sensing and transcriptional response abilities. We demonstrate the therapeutic potential of the receptor platform by engineering human primary T cells for multi-antigen recognition and production of dosed, bioactive payloads relevant to the treatment of disease. Our design framework enables the development of fully humanized and customizable transcriptional receptors for the programming of therapeutic cells suitable for clinical translation.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Receptores Artificiais , Humanos , Receptores de Antígenos de Linfócitos T/genética , Receptores Artificiais/genética , Biologia Sintética , Linfócitos T
2.
Cell ; 182(1): 245-261.e17, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32649877

RESUMO

Genomic studies of lung adenocarcinoma (LUAD) have advanced our understanding of the disease's biology and accelerated targeted therapy. However, the proteomic characteristics of LUAD remain poorly understood. We carried out a comprehensive proteomics analysis of 103 cases of LUAD in Chinese patients. Integrative analysis of proteome, phosphoproteome, transcriptome, and whole-exome sequencing data revealed cancer-associated characteristics, such as tumor-associated protein variants, distinct proteomics features, and clinical outcomes in patients at an early stage or with EGFR and TP53 mutations. Proteome-based stratification of LUAD revealed three subtypes (S-I, S-II, and S-III) related to different clinical and molecular features. Further, we nominated potential drug targets and validated the plasma protein level of HSP 90ß as a potential prognostic biomarker for LUAD in an independent cohort. Our integrative proteomics analysis enables a more comprehensive understanding of the molecular landscape of LUAD and offers an opportunity for more precise diagnosis and treatment.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Proteômica , Adenocarcinoma de Pulmão/genética , Povo Asiático/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Sistemas de Liberação de Medicamentos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Estadiamento de Neoplasias , Fosfoproteínas/metabolismo , Análise de Componente Principal , Prognóstico , Proteoma/metabolismo , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética
3.
Nature ; 629(8010): 235-243, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38499039

RESUMO

Biogenic monoamines-vital transmitters orchestrating neurological, endocrinal and immunological functions1-5-are stored in secretory vesicles by vesicular monoamine transporters (VMATs) for controlled quantal release6,7. Harnessing proton antiport, VMATs enrich monoamines around 10,000-fold and sequester neurotoxicants to protect neurons8-10. VMATs are targeted by an arsenal of therapeutic drugs and imaging agents to treat and monitor neurodegenerative disorders, hypertension and drug addiction1,8,11-16. However, the structural mechanisms underlying these actions remain unclear. Here we report eight cryo-electron microscopy structures of human VMAT1 in unbound form and in complex with four monoamines (dopamine, noradrenaline, serotonin and histamine), the Parkinsonism-inducing MPP+, the psychostimulant amphetamine and the antihypertensive drug reserpine. Reserpine binding captures a cytoplasmic-open conformation, whereas the other structures show a lumenal-open conformation stabilized by extensive gating interactions. The favoured transition to this lumenal-open state contributes to monoamine accumulation, while protonation facilitates the cytoplasmic-open transition and concurrently prevents monoamine binding to avoid unintended depletion. Monoamines and neurotoxicants share a binding pocket that possesses polar sites for specificity and a wrist-and-fist shape for versatility. Variations in this pocket explain substrate preferences across the SLC18 family. Overall, these structural insights and supporting functional studies elucidate the mechanism of vesicular monoamine transport and provide the basis to develop therapeutics for neurodegenerative diseases and substance abuse.


Assuntos
Monoaminas Biogênicas , Interações Medicamentosas , Proteínas Vesiculares de Transporte de Monoamina , Humanos , 1-Metil-4-fenilpiridínio/química , 1-Metil-4-fenilpiridínio/metabolismo , 1-Metil-4-fenilpiridínio/farmacologia , Anfetamina/química , Anfetamina/farmacologia , Anfetamina/metabolismo , Sítios de Ligação , Monoaminas Biogênicas/química , Monoaminas Biogênicas/metabolismo , Microscopia Crioeletrônica , Dopamina/química , Dopamina/metabolismo , Modelos Moleculares , Norepinefrina/química , Norepinefrina/metabolismo , Ligação Proteica , Prótons , Reserpina/farmacologia , Reserpina/química , Reserpina/metabolismo , Serotonina/química , Serotonina/metabolismo , Especificidade por Substrato , Proteínas Vesiculares de Transporte de Monoamina/química , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/ultraestrutura
4.
Nature ; 617(7959): 118-124, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37100915

RESUMO

Modern green revolution varieties of wheat (Triticum aestivum L.) confer semi-dwarf and lodging-resistant plant architecture owing to the Reduced height-B1b (Rht-B1b) and Rht-D1b alleles1. However, both Rht-B1b and Rht-D1b are gain-of-function mutant alleles encoding gibberellin signalling repressors that stably repress plant growth and negatively affect nitrogen-use efficiency and grain filling2-5. Therefore, the green revolution varieties of wheat harbouring Rht-B1b or Rht-D1b usually produce smaller grain and require higher nitrogen fertilizer inputs to maintain their grain yields. Here we describe a strategy to design semi-dwarf wheat varieties without the need for Rht-B1b or Rht-D1b alleles. We discovered that absence of Rht-B1 and ZnF-B (encoding a RING-type E3 ligase) through a natural deletion of a haploblock of about 500 kilobases shaped semi-dwarf plants with more compact plant architecture and substantially improved grain yield (up to 15.2%) in field trials. Further genetic analysis confirmed that the deletion of ZnF-B induced the semi-dwarf trait in the absence of the Rht-B1b and Rht-D1b alleles through attenuating brassinosteroid (BR) perception. ZnF acts as a BR signalling activator to facilitate proteasomal destruction of the BR signalling repressor BRI1 kinase inhibitor 1 (TaBKI1), and loss of ZnF stabilizes TaBKI1 to block BR signalling transduction. Our findings not only identified a pivotal BR signalling modulator but also provided a creative strategy to design high-yield semi-dwarf wheat varieties by manipulating the BR signal pathway to sustain wheat production.


Assuntos
Biomassa , Brassinosteroides , Grão Comestível , Transdução de Sinais , Triticum , Alelos , Brassinosteroides/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Deleção de Genes , Genes de Plantas , Giberelinas/metabolismo , Fenótipo , Triticum/classificação , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Proteínas de Plantas/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo
5.
Nature ; 608(7921): 69-73, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922500

RESUMO

Pressure-driven membranes is a widely used separation technology in a range of industries, such as water purification, bioprocessing, food processing and chemical production1,2. Despite their numerous advantages, such as modular design and minimal footprint, inevitable membrane fouling is the key challenge in most practical applications3. Fouling limits membrane performance by reducing permeate flux or increasing pressure requirements, which results in higher energetic operation and maintenance costs4-7. Here we report a hydraulic-pressure-responsive membrane (PiezoMem) to transform pressure pulses into electroactive responses for in situ self-cleaning. A transient hydraulic pressure fluctuation across the membrane results in generation of current pulses and rapid voltage oscillations (peak, +5.0/-3.2 V) capable of foulant degradation and repulsion without the need for supplementary chemical cleaning agents, secondary waste disposal or further external stimuli3,8-13. PiezoMem showed broad-spectrum antifouling action towards a range of membrane foulants, including organic molecules, oil droplets, proteins, bacteria and inorganic colloids, through reactive oxygen species (ROS) production and dielectrophoretic repulsion.

6.
EMBO J ; 42(9): e111241, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36970883

RESUMO

The accumulation of senescent cells is recognised as a driver of tissue and organismal ageing. One of the gold-standard hallmarks of a senescent cell is an increase in lysosomal content, as measured by senescence-associated ß-galactosidase (Senß-Gal) activity. The lysosome plays a central role in integrating mitogenic and stress cues to control cell metabolism, which is known to be dysregulated in senescence. Despite this, little is known about the cause and consequence of lysosomal biogenesis in senescence. We find here that lysosomes in senescent cells are dysfunctional; they have higher pH, increased evidence of membrane damage and reduced proteolytic capacity. The significant increase in lysosomal content is however sufficient to maintain degradative capacity of the cell to a level comparable to proliferating control cells. We demonstrate that increased nuclear TFEB/TFE3 supports lysosome biogenesis, is a hallmark of multiple forms of senescence and is required for senescent cell survival. TFEB/TFE3 are hypo-phosphorylated and show constitutive nuclear localisation in senescence. Evidence suggests that several pathways may contribute to TFEB/TFE3 dysregulation in senescence.


Assuntos
Núcleo Celular , Lisossomos , Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Núcleo Celular/metabolismo , Proliferação de Células , Lisossomos/metabolismo
7.
Plant Cell ; 36(6): 2272-2288, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421027

RESUMO

A number of cis-regulatory elements (CREs) conserved during evolution have been found to be responsible for phenotypic novelty and variation. Cucurbit crops such as cucumber (Cucumis sativus), watermelon (Citrullus lanatus), melon (Cucumis melo), and squash (Cucurbita maxima) develop fruits from an inferior ovary and share some similar biological processes during fruit development. Whether conserved regulatory sequences play critical roles in fruit development of cucurbit crops remains to be explored. In six well-studied cucurbit species, we identified 392,438 conserved noncoding sequences (CNSs), including 82,756 that are specific to cucurbits, by comparative genomics. Genome-wide profiling of accessible chromatin regions (ACRs) and gene expression patterns mapped 20,865 to 43,204 ACRs and their potential target genes for two fruit tissues at two key developmental stages in six cucurbits. Integrated analysis of CNSs and ACRs revealed 4,431 syntenic orthologous CNSs, including 1,687 cucurbit-specific CNSs that overlap with ACRs that are present in all six cucurbit crops and that may regulate the expression of 757 adjacent orthologous genes. CRISPR mutations targeting two CNSs present in the 1,687 cucurbit-specific sequences resulted in substantially altered fruit shape and gene expression patterns of adjacent NAC1 (NAM, ATAF1/2, and CUC2) and EXT-like (EXTENSIN-like) genes, validating the regulatory roles of these CNSs in fruit development. These results not only provide a number of target CREs for cucurbit crop improvement, but also provide insight into the roles of CREs in plant biology and during evolution.


Assuntos
Sequência Conservada , Frutas , Regulação da Expressão Gênica de Plantas , Frutas/genética , Frutas/crescimento & desenvolvimento , Sequências Reguladoras de Ácido Nucleico/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Cucurbita/genética , Cucurbita/crescimento & desenvolvimento , Citrullus/genética , Citrullus/crescimento & desenvolvimento , Citrullus/metabolismo , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta/genética
8.
Plant Cell ; 36(10): 4607-4621, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39133577

RESUMO

Complete disruption of critical genes is generally accompanied by severe growth and developmental defects, which dramatically hinder its utilization in crop breeding. Identifying subtle changes, such as single-nucleotide polymorphisms (SNPs), in critical genes that specifically modulate a favorable trait is a prerequisite to fulfill breeding potential. Here, we found 2 SNPs in the E-class floral organ identity gene cucumber (Cucumis sativus) SEPALLATA2 (CsSEP2) that specifically regulate fruit length. Haplotype (HAP) 1 (8G2667A) and HAP2 (8G2667T) exist in natural populations, whereas HAP3 (8A2667T) is induced by ethyl methanesulfonate mutagenesis. Phenotypic characterization of 4 near-isogenic lines and a mutant line showed that HAP2 fruits are significantly longer than those of HAP1, and those of HAP3 are 37.8% longer than HAP2 fruit. The increasing fruit length in HAP1-3 was caused by a decreasing inhibitory effect on CRABS CLAW (CsCRC) transcription (a reported positive regulator of fruit length), resulting in enhanced cell expansion. Moreover, a 7638G/A-SNP in melon (Cucumis melo) CmSEP2 modulates fruit length in a natural melon population via the conserved SEP2-CRC module. Our findings provide a strategy for utilizing essential regulators with pleiotropic effects during crop breeding.


Assuntos
Cucumis sativus , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Polimorfismo de Nucleotídeo Único , Polimorfismo de Nucleotídeo Único/genética , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Haplótipos/genética , Fenótipo
9.
Proc Natl Acad Sci U S A ; 121(4): e2316724121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38232284

RESUMO

Photoelectrochemical (PEC) carbon dioxide (CO2) reduction (CO2R) holds the potential to reduce the costs of solar fuel production by integrating CO2 utilization and light harvesting within one integrated device. However, the CO2R selectivity on the photocathode is limited by the lack of catalytic active sites and competition with the hydrogen evolution reaction. On the other hand, serious parasitic light absorption occurs on the front-side-illuminated photocathode due to the poor light transmittance of CO2R cocatalyst films, resulting in extremely low photocurrent density at the CO2R equilibrium potential. This paper describes the design and fabrication of a photocathode consisting of crystal phase-modulated Ag nanocrystal cocatalysts integrated on illumination-reaction decoupled heterojunction silicon (Si) substrate for the selective and efficient conversion of CO2. Ag nanocrystals containing unconventional hexagonal close-packed phases accelerate the charge transfer process in CO2R reaction, exhibiting excellent catalytic performance. Heterojunction Si substrate decouples light absorption from the CO2R catalyst layer, preventing the parasitic light absorption. The obtained photocathode exhibits a carbon monoxide (CO) Faradaic efficiency (FE) higher than 90% in a wide potential range, with the maximum FE reaching up to 97.4% at -0.2 V vs. reversible hydrogen electrode. At the CO2/CO equilibrium potential, a CO partial photocurrent density of -2.7 mA cm-2 with a CO FE of 96.5% is achieved in 0.1 M KHCO3 electrolyte on this photocathode, surpassing the expensive benchmark Au-based PEC CO2R system.

10.
Proc Natl Acad Sci U S A ; 121(13): e2316912121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38502698

RESUMO

Multi-principal element alloys (MPEAs) exhibit outstanding strength attributed to the complex dislocation dynamics as compared to conventional alloys. Here, we develop an atomic-lattice-distortion-dependent discrete dislocation dynamics framework consisted of random field theory and phenomenological dislocation model to investigate the fundamental deformation mechanism underlying massive dislocation motions in body-centered cubic MPEA. Amazingly, the turbulence of dislocation speed is identified in light of strong heterogeneous lattice strain field caused by short-range ordering. Importantly, the vortex from dislocation flow turbulence not only acts as an effective source to initiate dislocation multiplication but also induces the strong local pinning trap to block dislocation movement, thus breaking the strength-ductility trade-off.

11.
Trends Biochem Sci ; 47(8): 710-724, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35367113

RESUMO

Transcription is an essential and multistep process carried out by RNA polymerase (RNAP). In bacterial RNAP, in addition to the catalytic core domain, multiple other conserved domains are also identified to play regulatory roles in transcription. One such domain is the zinc-binding domain (ZBD) located at the N terminus of the largest subunit ß' in bacterial RNAP, whose homolog is also reported in eukaryotic RNAPs. Recent structural and biochemical studies have revealed various key roles of the conserved ß' ZBD during different steps of transcription. In this review, we summarize recent progress on the regulatory roles of this ß' ZBD in bacterial transcription.


Assuntos
RNA Polimerases Dirigidas por DNA , RNA Bacteriano , Bactérias/genética , Bactérias/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Transcrição Gênica , Zinco
12.
PLoS Pathog ; 20(9): e1012493, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39236072

RESUMO

Grasping the roles of epitopes in viral glycoproteins is essential for unraveling the structure and function of these proteins. Up to now, all identified epitopes have been found to either neutralize, have no effect on, or enhance viral entry into cells. Here, we used nanobodies (single-domain antibodies) as probes to investigate a unique epitope on the SARS-CoV-2 spike protein, located outside the protein's receptor-binding domain. Nanobody binding to this epitope enhances the cell entry of prototypic SARS-CoV-2, while neutralizing the cell entry of SARS-CoV-2 Omicron variant. Moreover, nanobody binding to this epitope promotes both receptor binding activity and post-attachment activity of prototypic spike, explaining the enhanced viral entry. The opposite occurs with Omicron spike, explaining the neutralized viral entry. This study reveals a unique epitope that can both enhance and neutralize viral entry across distinct viral variants, suggesting that epitopes may vary their roles depending on the viral context. Consequently, antibody therapies should be assessed across different viral variants to confirm their efficacy and safety.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Epitopos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Humanos , Epitopos/imunologia , COVID-19/imunologia , COVID-19/virologia , Anticorpos Neutralizantes/imunologia , Anticorpos de Domínio Único/imunologia , Anticorpos Antivirais/imunologia , Animais
13.
PLoS Pathog ; 20(9): e1012600, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39325826

RESUMO

A major challenge in antiviral antibody therapy is keeping up with the rapid evolution of viruses. Our research shows that nanobodies - single-domain antibodies derived from camelids - can be rapidly re-engineered to combat new viral strains through structure-guided in vitro evolution. Specifically, for viral mutations occurring at nanobody-binding sites, we introduce randomized amino acid sequences into nanobody residues near these mutations. We then select nanobody variants that effectively bind to the mutated viral target from a phage display library. As a proof of concept, we used this approach to adapt Nanosota-3, a nanobody originally identified to target the receptor-binding domain (RBD) of early Omicron subvariants, making it highly effective against recent Omicron subvariants. Remarkably, this adaptation process can be completed in less than two weeks, allowing drug development to keep pace with viral evolution and provide timely protection to humans.


Assuntos
SARS-CoV-2 , Anticorpos de Domínio Único , Anticorpos de Domínio Único/imunologia , Humanos , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Anticorpos Antivirais/imunologia , Animais , Mutação , COVID-19/imunologia , COVID-19/virologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética
14.
Plant Cell ; 35(11): 4173-4189, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37506254

RESUMO

Drought, which can induce osmotic stress, is the leading environmental constraint on crop productivity. Plants in both agricultural and natural settings have developed various mechanisms to cope with drought stress. The identification of genes associated with drought stress tolerance and understanding the underlying regulatory mechanisms are prerequisites for developing molecular manipulation strategies to address this issue. Here, we reported that the G-BOX FACTOR 14-3-3f (14-3-3 protein OsGF14f) positively modulates osmotic stress tolerance in rice (Oryza sativa). OsGF14f transgenic lines had no obvious change in crucial agronomic traits including yield and plant height. OsGF14f is transcriptionally induced by PEG treatment, and in rice, overexpression or knockout of this gene leads to enhanced or weakened osmotic stress tolerance, respectively. Furthermore, OsGF14f positively regulates abscisic acid (ABA) responses by interacting with the core ABA-responsive transcription factor BASIC LEUCINE ZIPPER 23 (OsbZIP23) to enhance its transcriptional regulation activity toward downstream target genes. Further genetic analysis showed that OsGF14f is required for the full function of OsbZIP23 in rice osmotic response, and OsGF14f-mediated osmotic stress tolerance partially depends on OsbZIP23. Interestingly, OsGF14f is a direct target gene of OsbZIP23. Taken together, our findings reveal a genetic and molecular framework by which the OsGF14f-OsbZIP23 complex modulates rice osmotic response, providing targets for developing drought-tolerant crops.


Assuntos
Oryza , Oryza/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Estresse Fisiológico/genética , Pressão Osmótica , Proteínas de Plantas/metabolismo , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo
15.
Circ Res ; 135(6): e133-e149, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39082135

RESUMO

BACKGROUND: Prostaglandin I2 synthesized by endothelial COX (cyclooxygenase) evokes potent vasodilation in some blood vessels but is paradoxically responsible for endothelium-dependent constriction (EDC) in others. Prostaglandin I2 production and EDC may be enhanced in diseases such as hypertension. However, how PGIS (prostaglandin I2 synthase) deficiency affects EDC and how this is implicated in the consequent cardiovascular pathologies remain largely unknown. METHODS: Experiments were performed with wild-type, Pgis knockout (Pgis-/-) and Pgis/thromboxane-prostanoid receptor gene (Tp) double knockout (Pgis-/-Tp-/-) mice and Pgis-/- mice transplanted with unfractionated wild-type or Cox-1-/- bone marrow cells, as well as human umbilical arteries. COX-derived prostanoids were measured by high-performance liquid chromatography-mass spectrometry. Vasomotor responses of distinct types of arteries were assessed by isometric force measurement. Parameters of hypertension, vascular remodeling, and cardiac hypertrophy in mice at different ages were monitored. RESULTS: PGF2α, PGE2, and a trace amount of PGD2, but not thromboxane A2 (TxA2), were produced in response to acetylcholine in Pgis-/- or PGIS-inhibited arteries. PGIS deficiency resulted in exacerbation or occurrence of EDC ex vivo and in vivo. Endothelium-dependent hyperpolarization was unchanged, but phosphorylation levels of eNOS (endothelial nitric oxide synthase) at Ser1177 and Thr495 were altered and NO production and the NO-dependent relaxation evoked by acetylcholine were remarkably reduced in Pgis-/- aortas. Pgis-/- mice developed high blood pressure and vascular remodeling at 16 to 17 weeks and subsequently cardiac hypertrophy at 24 to 26 weeks. Meanwhile, blood pressure and cardiac parameters remained normal at 8 to 10 weeks. Additional ablation of TP (TxA2 receptor) not only restrained EDC and the downregulation of NO signaling in Pgis-/- mice but also ameliorated the cardiovascular abnormalities. Stimulation of Pgis-/- vessels with acetylcholine in the presence of platelets led to increased TxA2 generation. COX-1 disruption in bone marrow-derived cells failed to affect the development of high blood pressure and vascular remodeling in Pgis-/- mice though it largely suppressed the increase of plasma TxB2 (TxA2 metabolite) level. CONCLUSIONS: Our study demonstrates that the non-TxA2 prostanoids/TP axis plays an essential role in mediating the augmentation of EDC and cardiovascular disorders when PGIS is deficient, suggesting TP as a promising therapeutic target in diseases associated with PGIS insufficiency.


Assuntos
Endotélio Vascular , Oxirredutases Intramoleculares , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prostaglandinas , Vasoconstrição , Animais , Humanos , Masculino , Camundongos , Cardiomegalia/genética , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/etiologia , Ciclo-Oxigenase 1/deficiência , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/deficiência , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/deficiência , Oxirredutases Intramoleculares/metabolismo , Prostaglandinas/metabolismo , Receptores de Tromboxanos/metabolismo , Receptores de Tromboxanos/genética , Transdução de Sinais , Tromboxano A2/metabolismo , Remodelação Vascular , Vasodilatação
16.
J Immunol ; 213(5): 743-752, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39058321

RESUMO

IFN regulatory factors (IRFs) are transcription factors that mediate homeostatic mechanisms of host defense against pathogens. In addition to IRF1-9, which are conserved across vertebrates, teleost fishes have two other IRFs, IRF10 and IRF11. In zebrafish (Danio rerio), IRF10 represses the expression of IFNφ1 and IFNφ3, whereas IRF11 exerts the opposite effect. In this study, we found IRF10 could significantly inhibit the expression of IFNφ1 and IFNφ3 induced by IFN11 to synergistically regulate type I IFN expression. To clarify the synergistically regulatory mechanism of IRF10 and IRF11 in type I IFN expression, we determined and analyzed the crystal structures of the DNA-binding domains (DBDs) of zebrafish IRF10 and IRF11 bound to DNA, as well as IRF11 DBD in apo form. The interactions of IRF10-DBD and IRF11-DBD with DNA backbone were elaborated in detail. Further analysis showed that IRF10 and IRF11 have the same binding patterns and comparable affinities with the IFN-sensitive response elements of IFNφ1 and IFNφ3 promoters. Therefore, IRF10 could function as a controlling factor for IRF11 by competitive binding of the IFN-sensitive response elements to coregulate the host IFN response. Accordingly, similar to IRF1 and IRF2 in mammals, IRF10 and IRF11 act as another pair of negative and positive regulators to balance the antiviral responses in fish.


Assuntos
DNA , Fatores Reguladores de Interferon , Peixe-Zebra , Animais , Peixe-Zebra/imunologia , DNA/imunologia , Fatores Reguladores de Interferon/metabolismo , Fatores Reguladores de Interferon/genética , Cristalografia por Raios X , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Ligação Proteica , Regulação da Expressão Gênica , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Interferons/metabolismo , Interferons/imunologia
17.
Nucleic Acids Res ; 52(11): 6145-6157, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783063

RESUMO

Native prokaryotic promoters share common sequence patterns, but are species dependent. For understudied species with limited data, it is challenging to predict the strength of existing promoters and generate novel promoters. Here, we developed PromoGen, a collection of nucleotide language models to generate species-specific functional promoters, across dozens of species in a data and parameter efficient way. Twenty-seven species-specific models in this collection were finetuned from the pretrained model which was trained on multi-species promoters. When systematically compared with native promoters, the Escherichia coli- and Bacillus subtilis-specific artificial PromoGen-generated promoters (PGPs) were demonstrated to hold all distribution patterns of native promoters. A regression model was developed to score generated either by PromoGen or by another competitive neural network, and the overall score of PGPs is higher. Encouraged by in silico analysis, we further experimentally characterized twenty-two B. subtilis PGPs, results showed that four of tested PGPs reached the strong promoter level while all were active. Furthermore, we developed a user-friendly website to generate species-specific promoters for 27 different species by PromoGen. This work presented an efficient deep-learning strategy for de novo species-specific promoter generation even with limited datasets, providing valuable promoter toolboxes especially for the metabolic engineering of understudied microorganisms.


Assuntos
Bacillus subtilis , Aprendizado Profundo , Escherichia coli , Regiões Promotoras Genéticas , Bacillus subtilis/genética , Escherichia coli/genética , Redes Neurais de Computação , Especificidade da Espécie
18.
Nucleic Acids Res ; 52(3): 1471-1482, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38197271

RESUMO

Transcription activation is a crucial step of regulation during transcription initiation and a classic check point in response to different stimuli and stress factors. The Escherichia coli NarL is a nitrate-responsive global transcription factor that controls the expression of nearly 100 genes. However, the molecular mechanism of NarL-mediated transcription activation is not well defined. Here we present a cryo-EM structure of NarL-dependent transcription activation complex (TAC) assembled on the yeaR promoter at 3.2 Å resolution. Our structure shows that the NarL dimer binds at the -43.5 site of the promoter DNA with its C-terminal domain (CTD) not only binding to the DNA but also making interactions with RNA polymerase subunit alpha CTD (αCTD). The key role of these NarL-mediated interactions in transcription activation was further confirmed by in vivo and in vitro transcription assays. Additionally, the NarL dimer binds DNA in a different plane from that observed in the structure of class II TACs. Unlike the canonical class II activation mechanism, NarL does not interact with σ4, while RNAP αCTD is bound to DNA on the opposite side of NarL. Our findings provide a structural basis for detailed mechanistic understanding of NarL-dependent transcription activation on yeaR promoter and reveal a potentially novel mechanism of transcription activation.


Assuntos
Proteínas de Escherichia coli , Nitratos , Ativação Transcricional , Proteínas de Bactérias/metabolismo , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Nitratos/metabolismo
19.
Proc Natl Acad Sci U S A ; 120(9): e2217256120, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36802424

RESUMO

Crystallographic control of crystals as catalysts with precise geometrical and chemical features is significantly important to develop sustainable chemistry, yet highly challenging. Encouraged by first principles calculations, precise structure control of ionic crystals could be realized by introducing an interfacial electrostatic field. Herein, we report an efficient in situ dipole-sourced electrostatic field modulation strategy using polarized ferroelectret, for crystal facet engineering toward challenging catalysis reactions, which avoids undesired faradic reactions or insufficient field strength by conventional external electric field. Resultantly, a distinct structure evolution from tetrahedron to polyhedron with different dominated facets of Ag3PO4 model catalyst was obtained by tuning the polarization level, and similar oriented growth was also realized by ZnO system. Theoretical calculations and simulation reveal that the generated electrostatic field can effectively guide the migration and anchoring of Ag+ precursors and free Ag3PO4 nuclei, achieving oriented crystal growth by thermodynamic and kinetic balance. The faceted Ag3PO4 catalyst exhibits high performance in photocatalytic water oxidation and nitrogen fixation for valuable chemicals production, validating the effectiveness and potential of this crystal regulation strategy. Such an electrically tunable growth concept by electrostatic field provides new synthetic insights and great opportunity to effectively tailor the crystal structures for facet-dependent catalysis.

20.
Proc Natl Acad Sci U S A ; 120(37): e2305380120, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669372

RESUMO

Proactively programming materials toward target nonlinear mechanical behaviors is crucial to realize customizable functions for advanced devices and systems, which arouses persistent explorations for rapid and efficient inverse design strategies. Herein, we propose a "mechanical Fourier transform" strategy to program mechanical behaviors of materials by mimicking the concept of Fourier transform. In this strategy, an arbitrary target force-displacement curve is decomposed into multiple cosine curves and a constant curve, each of which is realized by a rationally designed multistable module in an array-structured metamaterial. Various target curves with distinct shapes can be rapidly programmed and reprogrammed through only amplitude modulation on the modules. Two exemplary metamaterials are demonstrated to validate the strategy with a macroscale prototype based on magnet lattice and a microscale prototype based on an etched silicon wafer. This strategy applies to a variety of scales, constituents, and structures, and paves a way for the property programming of materials.

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