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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32814014

RESUMO

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Assuntos
Variação Genética/genética , Doenças Transmitidas por Carrapatos/microbiologia , Carrapatos/genética , Animais , Linhagem Celular , Vetores de Doenças , Especificidade de Hospedeiro/genética
2.
Nat Rev Mol Cell Biol ; 23(4): 250-265, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34987171

RESUMO

Aneuploidy, a genomic alternation characterized by deviations in the copy number of chromosomes, affects organisms from early development through to aging. Although it is a main cause of human pregnancy loss and a hallmark of cancer, how aneuploidy affects cellular function has been elusive. The last two decades have seen rapid advances in the understanding of the causes and consequences of aneuploidy at the molecular and cellular levels. These studies have uncovered effects of aneuploidy that can be beneficial or detrimental to cells and organisms in an environmental context-dependent and karyotype-dependent manner. Aneuploidy also imposes general stress on cells that stems from an imbalanced genome and, consequently, also an imbalanced proteome. These insights provide the fundamental framework for understanding the impact of aneuploidy in genome evolution, human pathogenesis and drug resistance.


Assuntos
Aneuploidia , Proteoma , Fenômenos Fisiológicos Celulares , Cromossomos , Genômica , Humanos , Proteoma/genética
3.
Chem Rev ; 124(1): 164-209, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38044580

RESUMO

The performance of a chemical reaction is critically dependent on the electronic and/or geometric structures of a material in heterogeneous catalysis. Over the past century, the Sabatier principle has already provided a conceptual framework for optimal catalyst design by adjusting the electronic structure of the catalytic material via a change in composition. Beyond composition, it is essential to recognize that the geometric atomic structures of a catalyst, encompassing terraces, edges, steps, kinks, and corners, have a substantial impact on the activity and selectivity of a chemical reaction. Crystal-phase engineering has the capacity to bring about substantial alterations in the electronic and geometric configurations of a catalyst, enabling control over coordination numbers, morphological features, and the arrangement of surface atoms. Modulating the crystallographic phase is therefore an important strategy for improving the stability, activity, and selectivity of catalytic materials. Nonetheless, a complete understanding of how the performance depends on the crystal phase of a catalyst remains elusive, primarily due to the absence of a molecular-level view of active sites across various crystal phases. In this review, we primarily focus on assessing the dependence of catalytic performance on crystal phases to elucidate the challenges and complexities inherent in heterogeneous catalysis, ultimately aiming for improved catalyst design.

4.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38824941

RESUMO

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamento farmacológico , Adulto , China/epidemiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimiorradioterapia/métodos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Cisplatino/uso terapêutico , Cisplatino/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/administração & dosagem , Adulto Jovem , Adolescente , Intervalo Livre de Progressão
5.
Plant Physiol ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365781

RESUMO

NONPHOTOTROPIC HYPOCOTYL3 (NPH3) is a key regulator of hypocotyl phototropism under both low- and high-intensity blue light (LBL/HBL), mediating phototropin1 (phot1) and phot2 signaling. NPH3 undergoes dephosphorylation and is released from the plasma membrane (PM) upon blue light irradiation. However, how its phosphorylation status and PM localization mediate phot1 and phot2 signaling in Arabidopsis (Arabidopsis thaliana) remains elusive. In this study, we found that fusing NPH3 with GFP at its C terminus (N3G) impaired its release from the PM, a defect exacerbated by a phosphorylation-deficient mutation, resulting in a dephosphorylated NPH3-GFP (N3AG). Unlike N3G, transgenic lines expressing N3AG exhibited defective hypocotyl phototropism under HBL, which could be rescued by myristoylation at the N-terminus of N3AG (mN3AG), indicating that NPH3 phosphorylation is not essential for HBL-induced phototropic responses when it is artificially anchored at the PM via its N terminus. Furthermore, genetic analysis revealed that N3AG anchored to the PM by its N terminus (as in mN3AG) only rescues phot1-mediated HBL responses, which require RPT2. However, N3AG failed to regulate phot2-mediated HBL signaling, regardless of its PM orientation. Taken together, our results revealed that NPH3 phosphorylation is essential for phot2-mediated hypocotyl phototropism under HBL, but is not required for phot1-mediated HBL signaling when the NPH3 N terminus is PM-anchored.

6.
Plant Physiol ; 196(2): 1475-1488, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38833579

RESUMO

The asymmetrical distribution of auxin supports high intensity blue light (HBL)-mediated phototropism. Flavonoids, secondary metabolites induced by blue light and TRANSPARENT TESTA GLABRA1 (TTG1), alter auxin transport. However, the role of TTG1 in HBL-induced phototropism in Arabidopsis (Arabidopsis thaliana) remains unclear. We found that TTG1 regulates HBL-mediated phototropism. HBL-induced degradation of CRYPTOCHROME 1 (CRY1) was repressed in ttg1-1, and depletion of CRY1 rescued the phototropic defects of the ttg1-1 mutant. Moreover, overexpression of CRY1 in a cry1 mutant background led to phototropic defects in response to HBL. These results indicated that CRY1 is involved in the regulation of TTG1-mediated phototropism in response to HBL. Further investigation showed that TTG1 physically interacts with CRY1 via its N-terminus and that the added TTG1 promotes the dimerization of CRY1. The interaction between TTG1 and CRY1 may promote HBL-mediated degradation of CRY1. TTG1 also physically interacted with blue light inhibitor of cryptochrome 1 (BIC1) and Light-Response Bric-a-Brack/Tramtrack/Broad 2 (LRB2), and these interactions either inhibited or promoted their interaction with CRY1. Exogenous gibberellins (GA) and auxins, two key plant hormones that crosstalk with CRY1, may confer the recovery of phototropic defects in the ttg1-1 mutant and CRY1-overexpressing plants. Our results revealed that TTG1 participates in the regulation of HBL-induced phototropism by modulating CRY1 levels, which are coordinated with GA or IAA signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Criptocromos , Luz , Fototropismo , Criptocromos/metabolismo , Criptocromos/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fototropismo/fisiologia , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Mutação/genética , Plantas Geneticamente Modificadas , Luz Azul
7.
Plant Physiol ; 195(3): 2309-2322, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38466216

RESUMO

Soil (or plant) water deficit accelerates plant reproduction. However, the underpinning molecular mechanisms remain unknown. By modulating cell division/number, ABSCISIC ACID-INSENSITIVE 5 (ABI5), a key bZIP (basic (region) leucine zippers) transcription factor, regulates both seed development and abiotic stress responses. The KIP-RELATED PROTEIN (KRP) cyclin-dependent kinases (CDKs) play an essential role in controlling cell division, and SHOOT MERISTEMLESS (STM) plays a key role in the specification of flower meristem identity. Here, our findings show that abscisic acid (ABA) signaling and/or metabolism in adjust reproductive outputs (such as rosette leaf number and open flower number) under water-deficient conditions in Arabidopsis (Arabidopsis thaliana) plants. Reproductive outputs increased under water-sufficient conditions but decreased under water-deficient conditions in the ABA signaling/metabolism mutants abscisic acid2-1 (aba2-1), aba2-11, abscisic acid insensitive3-1 (abi3-1), abi4-1, abi5-7, and abi5-8. Further, under water-deficient conditions, ABA induced-ABI5 directly bound to the promoter of KRP1, which encodes a CDK that plays an essential role in controlling cell division, and this binding subsequently activated KRP1 expression. In turn, KRP1 physically interacted with STM, which functions in the specification of flower meristem identity, promoting STM degradation. We further demonstrate that reproductive outputs are adjusted by the ABI5-KRP1-STM molecular module under water-deficient conditions. Together, our findings reveal the molecular mechanism by which ABA signaling and/or metabolism regulate reproductive development under water-deficient conditions. These findings provide insights that may help guide crop yield improvement under water deficiency.


Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Flores , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Ácido Abscísico/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Transdução de Sinais , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Reprodução , Mutação/genética , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/genética , Proteínas de Homeodomínio
8.
Nature ; 573(7774): 416-420, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31511699

RESUMO

Despite major progress in defining the functional roles of genes, a complete understanding of their influences is far from being realized, even in relatively simple organisms. A major milestone in this direction arose via the completion of the yeast Saccharomyces cerevisiae gene-knockout collection (YKOC), which has enabled high-throughput reverse genetics, phenotypic screenings and analyses of synthetic-genetic interactions1-3. Ensuing experimental work has also highlighted some inconsistencies and mistakes in the YKOC, or genome instability events that rebalance the effects of specific knockouts4-6, but a complete overview of these is lacking. The identification and analysis of genes that are required for maintaining genomic stability have traditionally relied on reporter assays and on the study of deletions of individual genes, but whole-genome-sequencing technologies now enable-in principle-the direct observation of genome instability globally and at scale. To exploit this opportunity, we sequenced the whole genomes of nearly all of the 4,732 strains comprising the homozygous diploid YKOC. Here, by extracting information on copy-number variation of tandem and interspersed repetitive DNA elements, we describe-for almost every single non-essential gene-the genomic alterations that are induced by its loss. Analysis of this dataset reveals genes that affect the maintenance of various genomic elements, highlights cross-talks between nuclear and mitochondrial genome stability, and shows how strains have genetically adapted to life in the absence of individual non-essential genes.


Assuntos
Genoma Fúngico/genética , Instabilidade Genômica , Saccharomyces cerevisiae/genética , Adaptação Biológica/genética , Técnicas de Inativação de Genes , Genoma Mitocondrial/genética , Sequenciamento Completo do Genoma
9.
Chem Soc Rev ; 53(19): 9609-9651, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39177226

RESUMO

The extensive utilization of plastic, as a symbol of modern technological society, has consumed enormous amounts of finite and non-renewable fossil resources and produced huge amounts of plastic wastes in the land or ocean, and thus recycling and reuse of the plastic wastes have great ecological and economic benefits. Closed-loop recyclable polymers with inherent recyclability can be readily depolymerized into monomers with high selectivity and purity and repolymerized into polymers with the same performance. They are deemed to be the next generation of recyclable polymers and have captured great and increasing attention from academia and industry. Herein, we provide an overview of readily closed-loop recyclable polymers based on monomer and polymer design and no-other-reactant-involved reversible ring-opening and addition polymerization reactions. The state-of-the-art of circular polymers is separately summarized and discussed based on different monomers, including lactones, thiolactones, cyclic carbonates, hindered olefins, cycloolefins, thermally labile olefin comonomers, cyclic disulfides, cyclic (dithio) acetals, lactams, Diels-Alder addition monomers, Michael addition monomers, anhydride-secondary amide monomers, and cyclic anhydride-aldehyde monomers, and polymers with activatable end groups. The polymerization and depolymerization mechanisms are clearly disclosed, and the evolution of the monomer structure, the polymerization and depolymerization conditions, the corresponding polymerization yield, molecular weight, performance of the polymers, monomer recovery, and depolymerization equipment are also systematically summarized and discussed. Furthermore, the challenges and future prospects are also highlighted.

10.
Am J Physiol Cell Physiol ; 327(3): C728-C736, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39069824

RESUMO

Chronic hypoxia (CH) is commonly associated with various cardiovascular diseases, with cardiac hypertrophy being the most frequently observed alteration. Metabolic remodeling is another consequence seen in the hypoxic heart. However, the mechanistic linkage between metabolic remodeling and cardiac hypertrophy in the hypoxic heart remains unclear. In this study, wild-type C57BL/6J mice were subjected to CH for 4 wk. Echocardiography and morphological analysis were used to assess the cardiac effects. We found that 4 wk of CH led to significant cardiac hypertrophy in the mice, whereas cardiac function remained unchanged compared with normoxic mice. In addition, CH induced an elevation in cardiac alpha-ketoglutarate (α-KG) content. Promoting α-KG degradation in the CH hearts prevented CH-induced cardiac hypertrophy but led to noticeable cardiac dysfunction. Mechanistically, α-KG promoted the transcription of hypertrophy-related genes by regulating histone methylation. Silencing lysine-specific demethylase 5 (KDM5), a histone demethylation enzyme, blunted α-KG-induced transcription of hypertrophy-related genes. These data suggest that α-KG is required for CH-induced cardiac remodeling, thus establishing a connection between metabolic changes and cardiac remodeling in hypoxic hearts.NEW & NOTEWORTHY We reported that alpha-ketoglutarate (α-KG) is indispensable for chronic hypoxia (CH)-induced cardiac remodeling, which builds the bridge between metabolic intermediates and cardiac remodeling.


Assuntos
Cardiomegalia , Hipóxia , Ácidos Cetoglutáricos , Camundongos Endogâmicos C57BL , Remodelação Ventricular , Animais , Ácidos Cetoglutáricos/metabolismo , Hipóxia/metabolismo , Remodelação Ventricular/efeitos dos fármacos , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Cardiomegalia/genética , Camundongos , Masculino , Doença Crônica , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia
11.
J Am Chem Soc ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352731

RESUMO

The trifluoromethylthio group (SCF3) has gained increasing prominence in the field of drug design and development due to its unique electronic properties, remarkable stability, and high lipophilicity, but its derivatives remain challenging to access, especially in an enantioselective manner. In this Communication, we present an enantioselective iridium-catalyzed trifluoromethylthiolation of the propargylic C(sp3)-H bonds of alkynes. This protocol demonstrates its efficacy across a diverse array of alkyne substrates, including B- and Si-protected terminal alkynes as well as those derived from natural products and pharmaceuticals, to give trifluoromethyl thioethers with good to excellent yield and stereoselectivity. Moreover, this protocol could be modified to access enantioenriched difluoromethyl and chlorodifluoromethyl thioethers (SCF2H and SCF2Cl derivatives), significantly expanding the space of synthetically accessible enantioenriched fluoroorganic compounds.

12.
J Am Chem Soc ; 146(23): 16112-16118, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38803151

RESUMO

Thermosets, characterized by their permanent cross-linked networks, present significant challenges in recyclability and brittleness. In this work, we explore a polarized Knoevenagel C═C metathesis reaction for the development of rigid yet tough and malleable thermosets. Initial investigation on small molecule model reactions reveals the feasibility of conducting the base-catalyzed C═C metathesis reaction in a solvent-free environment. Subsequently, thermosetting poly(α-cyanocinnamate)s (PCCs) were synthesized via Knoevenagel condensation between a triarm cyanoacetate star and a dialdehyde. The thermal and mechanical properties of the developed PCCs can be easily modulated by altering the structure of the dialdehyde. Remarkably, the introduction of ether groups into the PCC leads to a combination of high rigidity and toughness with Young's modulus of ∼1590 MPa, an elongation at break of ∼79%, and a toughness reaching ∼30 MJ m3. These values are competitive to traditional thermosets, in Young's modulus but far exceed them in ductility and toughness. Moreover, the C═C metathesis facilitates stress relaxation within the bulk polymer networks, thus rendering PCCs excellent malleability and reprocessability. This work overcomes the traditional limitations of thermosets, introducing groundbreaking insights for the design of rigid yet tough and malleable thermosets, and contributing significantly to the sustainability of materials.

13.
J Am Chem Soc ; 146(14): 9920-9927, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557104

RESUMO

Plastic recycling is critical for waste management and achieving a circular economy, but it entails difficult trade-offs between performance and recyclability. Here, we report a thermoset, poly(α-cyanocinnamate) (PCC), synthesized using Knoevenagel condensation between terephthalaldehyde (TPA) and a triarm cyanoacetate star, that tackles this difficulty by harnessing its intrinsically conjugated and dynamic chemical characteristics. PCCs exhibit extraordinary thermal and mechanical properties with a typical Tg of ∼178 °C, Young's modulus of 3.8 GPa, and tensile strength of 102 MPa, along with remarkable flexibility and dimensional and chemical stabilities. Furthermore, end-of-life PCCs can be selectively degraded and partially recycled back into one starting monomer TPA for a new production cycle or reprocessed through dynamic exchange aided by cyanoacetate chain-ends. This study lays the scientific groundwork for the design of robust and recyclable thermosets, with transformative potential in plastic engineering.

14.
Mol Pain ; : 17448069241260349, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795338

RESUMO

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disease characterized by chronic visceral pain with a complex etiology and challenging treatment. Although accumulating evidence supports the involvement of central nervous system sensitization in the development of visceral pain, the precise molecular mechanisms remain incompletely understood. In this study, we highlight the critical regulatory role of lysine-specific demethylase 6B (KDM6B) in the anterior cingulate cortex (ACC) in chronic visceral pain. To simulate clinical IBS conditions, we utilized the neonatal maternal deprivation (NMD) mouse model. Our results demonstrated that NMD induced chronic visceral pain and anxiety-like behaviors in mice. Notably, the protein expression level of KDM6B significantly increased in the ACC of NMD mice, leading to a reduction in the expression level of H32K7me3. Immunofluorescence staining revealed that KDM6B primarily co-localizes with neurons in the ACC, with minimal presence in microglia and astrocytes. Injecting GSK-J4 (a KDM6B-specific inhibitor) into ACC of NMD mice, resulted in a significant alleviation in chronic visceral pain and anxiety-like behaviors, as well as a remarkable reduction in NR2B expression level. ChIP assay further indicated that KDM6B regulates NR2B expression by influencing the demethylation of H3K27me3. In summary, our findings underscore the critical role of KDM6B in regulating chronic visceral pain and anxiety-like behaviors in NMD mice. These insights provide a basis for further understanding the molecular pathways involved in IBS and may pave the way for targeted therapeutic interventions.

15.
Small ; : e2406958, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39279402

RESUMO

With the depletion of petroleum resources, the development of sustainable alternatives for plastic substitutes has grown in importance. It is urgently desirable yet challenging to design high-performance polyesters with extensive mechanical and prominent gas barrier properties. This work uses bio-based PBF polyester as a matrix, "leaf-shaped" carbon nanotube@boron nitride nano-sheet (CNT@BNNS) covalent hetero-junctions as functional fillers, to fabricate CNT@BNNS/PBF (denoted as CBNP) composite films through an "in-situ polymerizing and hot-pressing" strategy. The covalent CNT "stem" suppresses the re-stacking of BNNS "leaf", endowing hetero-structured CNT@BNNS illustrates superior stress transfer and physical barrier effect. The covalently hetero structure and high orientation degree of CNT@BNNS greatly improve the comprehensive performance of the CBNP composites, including excellent mechanical (strength of 76 MPa, modulus of 2.3 GPa, toughness of 85 MJ m-3, elongation at break of 193%) and gas barrier (O2 of 0.015 barrer, and H2O of 1.1 × 10-14 g cm cm-2 s-1 Pa-1) properties that are much higher than for pure PBF or other-type polyesters, and most engineering plastics. Moreover, the CBNP composites also boast easy recyclability, overcoming the tradeoff between high performance and easy recycling of traditional plastics, which makes the polyester composite competitive as a plastic substitute.

16.
Plant Physiol ; 194(1): 391-407, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37738410

RESUMO

Exposure of dark-grown etiolated seedlings to light triggers the transition from skotomorphogenesis/etiolation to photomorphogenesis/de-etiolation. In the life cycle of plants, de-etiolation is essential for seedling development and plant survival. The mobilization of soluble sugars (glucose [Glc], sucrose, and fructose) derived from stored carbohydrates and lipids to target organs, including cotyledons, hypocotyls, and radicles, underpins de-etiolation. Therefore, dynamic carbohydrate biochemistry is a key feature of this phase transition. However, the molecular mechanisms coordinating carbohydrate status with the cellular machinery orchestrating de-etiolation remain largely opaque. Here, we show that the Glc sensor HEXOKINASE 1 (HXK1) interacts with GROWTH REGULATOR FACTOR5 (GRF5), a transcriptional activator and key plant growth regulator, in Arabidopsis (Arabidopsis thaliana). Subsequently, GRF5 directly binds to the promoter of phytochrome A (phyA), encoding a far-red light (FR) sensor/cotyledon greening inhibitor. We demonstrate that the status of Glc within dark-grown etiolated cotyledons determines the de-etiolation of seedlings when exposed to light irradiation by the HXK1-GRF5-phyA molecular module. Thus, following seed germination, accumulating Glc within dark-grown etiolated cotyledons stimulates a HXK1-dependent increase of GRF5 and an associated decrease of phyA, triggering the perception, amplification, and relay of HXK1-dependent Glc signaling, thereby facilitating the de-etiolation of seedlings following light irradiation. Our findings, therefore, establish how cotyledon carbohydrate signaling under subterranean darkness is sensed, amplified, and relayed, determining the phase transition from skotomorphogenesis to photomorphogenesis on exposure to light irradiation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Plântula/metabolismo , Cotilédone/metabolismo , Estiolamento , Glucose/metabolismo , Luz , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fitocromo A/metabolismo , Regulação da Expressão Gênica de Plantas
17.
BMC Cancer ; 24(1): 665, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822321

RESUMO

PURPOSE: To explore the clinical value of tumor abnormal protein (TAP) in the diagnosis and prognosis evaluation of prostate cancer. METHODS: This study enrolled a total of 265 patients who underwent prostate biopsy procedures from December 2017. TAP levels were assayed in their blood samples using a validated TAP testing kit. Comprehensive pathological assessments, including Gleason scores, TNM staging, and AJCC prognosis stages, were conducted on prostate cancer patients. Further analysis was carried out to examine the correlation between TAP expression levels and various clinical characteristics. RESULTS: A significantly elevated TAP concentration was discerned in prostate cancer patients relative to those with benign prostate hyperplasia. Moreover, a significantly elevated TAP expression was detected in prostate cancer patients with high Gleason score (≥ 8) and advanced stages (III and IV), as compared to those with Gleason scores of 6 and 7 and lower stages (I and II). When diagnosing prostate cancer in gray area of PSA, TAP demonstrated superior diagnostic capabilities over PSA alone, with higher diagnostic sensitivity, specificity and accuracy than fPSA/tPSA ratio. Additionally, post-surgical or hormonal treatment, there was a marked reduction in TAP expression level among prostate cancer patients. CONCLUSION: The assessment of TAP presents itself as a promising tool for early diagnosis and holds potential for sensitivity in monitoring treatment reponse in prostate cancer patients.


Assuntos
Biomarcadores Tumorais , Gradação de Tumores , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico , Idoso , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , Prognóstico , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Proteínas de Neoplasias/sangue , Sensibilidade e Especificidade
18.
Langmuir ; 40(21): 10908-10915, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38739034

RESUMO

Band 3, or anion exchanger 1 (AE1), is one of the indispensable transmembrane proteins involved in the effective respiratory process of the human body and is primarily responsible for the exchange of bicarbonate and chloride anions across the plasma membrane of erythrocyte. However, the molecular mechanism of ion transport of Band 3 is not completely understood, yet. In this work, we systematically investigate the key binding sites of bicarbonate ions in Band 3 and the impact of cholesterol (CHOL) in lipid bilayers on bicarbonate ion binding using all-atom molecular dynamics (MD) simulations. We examine the dynamics of interactions of bicarbonate ions with Band 3 in the microsecond time scale and calculate the binding free energy of the anion in Band 3. The results indicate that the residue R730 of Band 3 is the most probable binding site for bicarbonate ions. CHOL enhances the bicarbonate ion binding by influencing the conformational stability of Band 3 and compressing the volume of the Band 3 cavity. These findings provide some insights into the bicarbonate ion binding in Band 3 and are helpful for understanding the anion exchange of Band 3.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito , Bicarbonatos , Colesterol , Simulação de Dinâmica Molecular , Proteína 1 de Troca de Ânion do Eritrócito/química , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Bicarbonatos/química , Bicarbonatos/metabolismo , Colesterol/química , Colesterol/metabolismo , Humanos , Sítios de Ligação , Ligação Proteica , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo
19.
Mol Cell Biochem ; 479(12): 3405-3424, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38367118

RESUMO

The E3 ubiquitin ligase Tripartite-motif 3 (TRIM3) is known to play a crucial role in tumor suppression in various tumors through different mechanisms. However, its function and mechanism in ovarian cancer have yet to be elucidated. Our study aims to investigate the expression of TRIM3 in ovarian cancer and evaluate its role in the development of the disease. Our findings revealed a significant decrease in TRIM3 mRNA and protein levels in ovarian cancer tissues and cells when compared to normal ovarian epithelial tissues and cells. Furthermore, we observed a negative correlation between the protein level of TRIM3 and the FIGO stage, as well as a positive correlation with the survival of ovarian cancer patients. Using gain and loss of function experiments, we demonstrated that TRIM3 can inhibit cell proliferation, migration and invasion of the ovarian cancer cells in vitro, as well as suppress tumor growth in vivo. Mechanistic studies showed that TRIM3 interacts with lactate dehydrogenase A, a key enzyme in the glycolytic pathway, through its B-box and coiled-coil domains and induces its ubiquitination and proteasomal degradation, leading to the inhibition of glycolytic ability in ovarian cancer cells. RNA-sequencing analysis revealed significant alterations in the phosphatidylinositol signaling pathways upon TRIM3 overexpression. Additionally, overexpression of TRIM3 inhibited the phosphorylation of AKT. In conclusion, our study demonstrated that TRIM3 exerts a tumor-suppressive effect in ovarian cancer, at least partially, by downregulating LDHA and inhibiting the AKT signaling pathway, and thus leading to the inhibition of glycolysis and limiting the growth of ovarian cancer cells.


Assuntos
Regulação para Baixo , Neoplasias Ovarianas , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Feminino , Humanos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Linhagem Celular Tumoral , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Proliferação de Células , Camundongos , Regulação Neoplásica da Expressão Gênica , Animais , Progressão da Doença , Camundongos Nus , Movimento Celular , Proteínas de Transporte , L-Lactato Desidrogenase
20.
Biomacromolecules ; 25(3): 1825-1837, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38336482

RESUMO

A synthetic biopolymer derived from furandicarboxylic acid monomer and hydroxyethyl-terminated poly(ether sulfone) is presented. The synthesis involves 4,4'-dichlorodiphenyl sulfone and 4,4-dihydroxydiphenyl sulfone, resulting in poly(butylene furandicarboxylate)-poly(ether sulfone) copolyesters (PBFES) through melt polycondensation with titanium-catalyzed polymerization. This facile method yields segmented polyesters incorporating polysulfone, creating a versatile group of high-temperature thermoplastics with adjustable thermomechanical properties. The PBFES copolyesters demonstrate an impressive tensile modulus of 2830 MPa and a tensile strength of 84 MPa for PBFES55. Additionally, the poly(ether sulfone) unit imparts a relatively high glass transition temperature (Tg), ranging from 36.6 °C for poly(butylene 2,5-furandicarboxylate) to 112.3 °C for PBFES62. Moreover, the complete amorphous film of PBFES exhibits excellent transparency and solvent resistance, making it suitable for applications, such as food packaging materials.


Assuntos
Alcenos , Materiais Biocompatíveis , Poliésteres , Polímeros , Sulfonas , Éteres
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