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1.
Cell ; 179(1): 147-164.e20, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31539493

RESUMO

Long-distance RNA transport enables local protein synthesis at metabolically-active sites distant from the nucleus. This process ensures an appropriate spatial organization of proteins, vital to polarized cells such as neurons. Here, we present a mechanism for RNA transport in which RNA granules "hitchhike" on moving lysosomes. In vitro biophysical modeling, live-cell microscopy, and unbiased proximity labeling proteomics reveal that annexin A11 (ANXA11), an RNA granule-associated phosphoinositide-binding protein, acts as a molecular tether between RNA granules and lysosomes. ANXA11 possesses an N-terminal low complexity domain, facilitating its phase separation into membraneless RNA granules, and a C-terminal membrane binding domain, enabling interactions with lysosomes. RNA granule transport requires ANXA11, and amyotrophic lateral sclerosis (ALS)-associated mutations in ANXA11 impair RNA granule transport by disrupting their interactions with lysosomes. Thus, ANXA11 mediates neuronal RNA transport by tethering RNA granules to actively-transported lysosomes, performing a critical cellular function that is disrupted in ALS.


Assuntos
Anexinas/metabolismo , Transporte Axonal/fisiologia , Grânulos Citoplasmáticos/metabolismo , Lisossomos/metabolismo , RNA/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Animais , Animais Geneticamente Modificados , Anexinas/genética , Axônios/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Mutação , Ligação Proteica , Ratos/embriologia , Ratos Sprague-Dawley , Transfecção , Peixe-Zebra
2.
Cell ; 175(6): 1457-1459, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30500530

RESUMO

The use of optogenetic approaches has revealed new roles for intracellular protein condensates described in two papers in this issue of Cell (Bracha et. al., 2018; Shin et al., 2018). These results show that growing condensates are able to exert mechanical forces resulting in chromatin rearrangement, establishing a new role for liquid-liquid phase separation in the mechanobiology of the cell.


Assuntos
Proteínas , Biofísica , Citoplasma
3.
Nat Immunol ; 20(3): 313-325, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30718913

RESUMO

N-myristoyltransferase (NMT) attaches the fatty acid myristate to the N-terminal glycine of proteins to sort them into soluble and membrane-bound fractions. Function of the energy-sensing AMP-activated protein kinase, AMPK, is myristoylation dependent. In rheumatoid arthritis (RA), pathogenic T cells shift glucose away from adenosine tri-phosphate production toward synthetic and proliferative programs, promoting proliferation, cytokine production, and tissue invasion. We found that RA T cells had a defect in NMT1 function, which prevented AMPK activation and enabled unopposed mTORC1 signaling. Lack of the myristate lipid tail disrupted the lysosomal translocation and activation of AMPK. Instead, myristoylation-incompetent RA T cells hyperactivated the mTORC1 pathway and differentiated into pro-inflammatory TH1 and TH17 helper T cells. In vivo, NMT1 loss caused robust synovial tissue inflammation, whereas forced NMT1 overexpression rescued AMPK activation and suppressed synovitis. Thus, NMT1 has tissue-protective functions by facilitating lysosomal recruitment of AMPK and dampening mTORC1 signaling.


Assuntos
Proteínas Quinases Ativadas por AMP/imunologia , Aciltransferases/imunologia , Artrite Reumatoide/imunologia , Sinovite/imunologia , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Adulto , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Células Cultivadas , Ativação Enzimática/imunologia , Feminino , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Pessoa de Meia-Idade , Interferência de RNA , Sinovite/genética , Sinovite/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto Jovem
4.
Nat Immunol ; 18(9): 1025-1034, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28737753

RESUMO

Pathogenic T cells in individuals with rheumatoid arthritis (RA) infiltrate non-lymphoid tissue sites, maneuver through extracellular matrix and form lasting inflammatory microstructures. Here we found that RA T cells abundantly express the podosome scaffolding protein TKS5, which enables them to form tissue-invasive membrane structures. TKS5 overexpression was regulated by the intracellular metabolic environment of RA T cells-specifically, by reduced glycolytic flux that led to deficiencies in ATP and pyruvate. ATPlopyruvatelo conditions triggered fatty acid biosynthesis and the formation of cytoplasmic lipid droplets. Restoration of pyruvate production or inhibition of fatty acid synthesis corrected the tissue-invasiveness of RA T cells in vivo and reversed their proarthritogenic behavior. Thus, metabolic control of T cell locomotion provides new opportunities to interfere with T cell invasion into specific tissue sites.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Artrite Psoriásica/metabolismo , Artrite Reumatoide/metabolismo , Linfócitos T/metabolismo , Trifosfato de Adenosina/metabolismo , Artrite Psoriásica/imunologia , Artrite Reumatoide/imunologia , Movimento Celular/imunologia , Ácidos Graxos/biossíntese , Feminino , Perfilação da Expressão Gênica , Glicólise/imunologia , Humanos , Immunoblotting , Imuno-Histoquímica , Inflamação , Masculino , Pessoa de Meia-Idade , Ácido Pirúvico/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Membrana Sinovial/citologia , Membrana Sinovial/imunologia , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Linfócitos T/imunologia
5.
Nucleic Acids Res ; 52(11): 6472-6489, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38752489

RESUMO

Orphan nuclear receptors (NRs), such as COUP-TF1, COUP-TF2, EAR2, TR2 and TR4, are implicated in telomerase-negative cancers that maintain their telomeres through the alternative lengthening of telomeres (ALT) mechanism. However, how telomere association of orphan NRs is involved in ALT activation remains unclear. Here, we demonstrate that telomeric tethering of orphan NRs in human fibroblasts initiates formation of ALT-associated PML bodies (APBs) and features of ALT activity, including ALT telomere DNA synthesis, telomere sister chromatid exchange, and telomeric C-circle generation, suggesting de novo ALT induction. Overexpression of orphan NRs exacerbates ALT phenotypes in ALT cells, while their depletion limits ALT. Orphan NRs initiate ALT via the zinc finger protein 827, suggesting the involvement of chromatin structure alterations for ALT activation. Furthermore, we found that orphan NRs and deficiency of the ALT suppressor ATRX-DAXX complex operate in concert to promote ALT activation. Moreover, PML depletion by gene knockout or arsenic trioxide treatment inhibited ALT induction in fibroblasts and ALT cancer cells, suggesting that APB formation underlies the orphan NR-induced ALT activation. Importantly, arsenic trioxide administration abolished APB formation and features of ALT activity in ALT cancer cell line-derived mouse xenografts, suggesting its potential for further therapeutic development to treat ALT cancers.


Assuntos
Fibroblastos , Proteína da Leucemia Promielocítica , Homeostase do Telômero , Humanos , Animais , Proteína da Leucemia Promielocítica/metabolismo , Proteína da Leucemia Promielocítica/genética , Camundongos , Fibroblastos/metabolismo , Telômero/metabolismo , Telômero/genética , Proteína Nuclear Ligada ao X/genética , Proteína Nuclear Ligada ao X/metabolismo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Troca de Cromátide Irmã , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Linhagem Celular Tumoral , Trióxido de Arsênio/farmacologia , Chaperonas Moleculares
6.
Proc Natl Acad Sci U S A ; 120(33): e2301366120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549257

RESUMO

A wide range of macromolecules can undergo phase separation, forming biomolecular condensates in living cells. These membraneless organelles are typically highly dynamic, formed reversibly, and carry out essential functions in biological systems. Crucially, however, a further liquid-to-solid transition of the condensates can lead to irreversible pathological aggregation and cellular dysfunction associated with the onset and development of neurodegenerative diseases. Despite the importance of this liquid-to-solid transition of proteins, the mechanism by which it is initiated in normally functional condensates is unknown. Here we show, by measuring the changes in structure, dynamics, and mechanics in time and space, that single-component FUS condensates do not uniformly convert to a solid gel, but rather that liquid and gel phases coexist simultaneously within the same condensate, resulting in highly inhomogeneous structures. Furthermore, our results show that this transition originates at the interface between the condensate and the dilute continuous phase, and once initiated, the gelation process propagates toward the center of the condensate. To probe such spatially inhomogeneous rheology during condensate aging, we use a combination of established micropipette aspiration experiments together with two optical techniques, spatial dynamic mapping and reflective confocal dynamic speckle microscopy. These results reveal the importance of the spatiotemporal dimension of the liquid-to-solid transition and highlight the interface of biomolecular condensates as a critical element in driving pathological protein aggregation.


Assuntos
Condensados Biomoleculares , Agregação Patológica de Proteínas , Humanos , Microscopia Confocal , Reologia , Proteína FUS de Ligação a RNA
7.
J Virol ; : e0202023, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884472

RESUMO

Human noroviruses (HuNoVs) are a diverse group of RNA viruses that cause endemic and pandemic acute viral gastroenteritis. Previously, we reported that many HuNoV strains require bile or bile acid (BA) to infect human jejunal intestinal enteroid cultures. BA was not essential for the replication of a pandemic-causing GII.4 HuNoV strain. We found the hydrophobic BA glycochenodeoxycholic acid (GCDCA) promotes the replication of the BA-dependent strain GII.3 in jejunal enteroids. Furthermore, we found that inhibition of the G-protein-coupled BA receptor, sphingosine-1-phosphate receptor 2 (S1PR2), by JTE-013, reduced GII.3 infection dose-dependently and inhibited GII.3 cellular uptake in enteroids. Herein, we sought to determine whether S1PR2 is required for other BA-dependent HuNoV strains, the BA-independent GII.4, and whether S1PR2 is required for BA-dependent HuNoV infection in HIEs from other small intestinal segments. We found a second S1PR2 inhibitor, GLPG2938, reduces GII.3 infection dose-dependently, and an S1PR2 agonist (CYM-5520) enhances GII.3 replication in the absence of GCDCA. GII.3 replication also is abrogated in the presence of JTE-013 and CYM-5520. JTE-013 inhibition of S1PR2 in jejunal HIEs reduces GI.1, GII.3, and GII.17 (BA-dependent) but not GII.4 Sydney (BA-independent) infection, providing additional evidence of strain-specific differences in HuNoV infection. Finally, GII.3 infection of duodenal, jejunal, and ileal lines derived from the same individual is reduced with S1PR2 inhibition, indicating a common mechanism of BA-dependent infection among multiple segments of the small intestine. Our results support a model where BA-dependent HuNoVs exploit BA effects on S1PR2 to infect the entire small intestine.IMPORTANCEHuman noroviruses (HuNoVs) are important viral human pathogens that cause both outbreaks and sporadic gastroenteritis. These viruses are diverse, and many strains are capable of infecting humans. Our previous studies have identified strain-specific requirements for hydrophobic bile acids (BAs) to infect intestinal epithelial cells. Moreover, we identified a BA receptor, sphingosine-1-phosphate receptor 2 (S1PR2), required for infection by a BA-dependent strain. To better understand how various HuNoV strains enter and infect the small intestine and the role of S1PR2 in HuNoV infection, we evaluated infection by additional HuNoV strains using an expanded repertoire of intestinal enteroid cell lines. We found that multiple BA-dependent strains, but not a BA-independent strain, all require S1PR2 for infection. In addition, BA-dependent infection requires S1PR2 in multiple segments of the small intestine. Together, these results indicate that S1PR2 has value as a potential therapeutic target for BA-dependent HuNoV infection.

8.
Plant Physiol ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976569

RESUMO

Temperature is one of the key environmental factors influencing crop fertility and yield. Understanding how plants sense and respond to temperature changes is, therefore, crucial for improving agricultural production. In this study, we characterized a temperature-sensitive male-sterile mutant in rice (Oryza sativa), glutamyl-tRNA synthetase 1-2 (ers1-2), that shows reduced fertility at high temperatures and restored fertility at low temperatures. Mutation of ERS1 resulted in severely delayed pollen development and meiotic progression at high temperatures, eventually leading to male sterility. Moreover, meiosis-specific events, including synapsis and crossover formation, were also delayed in ers1-2 compared with the wild type. However, these defects were all mitigated by growing ers1-2 at low temperatures. Transcriptome analysis and measurement of ascorbate, glutathione, and hydrogen peroxide (H2O2) contents revealed that the delayed meiotic progression and male sterility in ers1-2 were strongly associated with changes in reactive oxygen species (ROS) homeostasis. At high temperatures, ers1-2 exhibited decreased accumulation of ROS scavengers and overaccumulation of ROS. In contrast, at low temperatures, the antioxidant system of ROS was more active, and ROS contents were lower. These data suggest that ROS homeostasis in ers1-2 is disrupted at high temperatures but restored at low temperatures. We speculate that ERS1 dysfunction leads to changes in ROS homeostasis under different conditions, resulting in delayed or rescued meiotic progression and thermosensitive male fertility. ers1-2 may hold great potential as a thermosensitive material for crop heterosis breeding.

9.
Plant Physiol ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478471

RESUMO

During meiotic prophase I, chromosomes undergo large-scale dynamics to allow homologous chromosome pairing, prior to which chromosome ends attach to the inner nuclear envelope and form a chromosomal bouquet. Chromosome pairing is crucial for homologous recombination and accurate chromosome segregation during meiosis. However, the specific mechanism by which homologous chromosomes recognize each other is poorly understood. Here, we investigated the process of homologous chromosome pairing during early prophase I of meiosis in rice (Oryza sativa) using pooled oligo probes specific to an entire chromosome or chromosome arm. We revealed that chromosome pairing begins from both ends and extends towards the center from early zygotene through late zygotene. Genetic analysis of both trisomy and autotetraploidy also showed that pairing initiation is induced by both ends of a chromosome. However, healed ends that lack the original terminal regions on telocentric and acrocentric chromosomes cannot initiate homologous chromosome pairing, even though they may still enter the telomere clustering region at the bouquet stage. Furthermore, a chromosome that lacks the distal parts on both sides loses the ability to pair with other intact chromosomes. Thus, the native ends of chromosomes play a crucial role in initiating homologous chromosome pairing during meiosis and likely have a substantial impact on genome differentiation.

10.
Immunity ; 45(4): 903-916, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27742546

RESUMO

Immune aging manifests with a combination of failing adaptive immunity and insufficiently restrained inflammation. In patients with rheumatoid arthritis (RA), T cell aging occurs prematurely, but the mechanisms involved and their contribution to tissue-destructive inflammation remain unclear. We found that RA CD4+ T cells showed signs of aging during their primary immune responses and differentiated into tissue-invasive, proinflammatory effector cells. RA T cells had low expression of the double-strand-break repair nuclease MRE11A, leading to telomeric damage, juxtacentromeric heterochromatin unraveling, and senescence marker upregulation. Inhibition of MRE11A activity in healthy T cells induced the aging phenotype, whereas MRE11A overexpression in RA T cells reversed it. In human-synovium chimeric mice, MRE11Alow T cells were tissue-invasive and pro-arthritogenic, and MRE11A reconstitution mitigated synovitis. Our findings link premature T cell aging and tissue-invasiveness to telomere deprotection and heterochromatin unpacking, identifying MRE11A as a therapeutic target to combat immune aging and suppress dysregulated tissue inflammation.


Assuntos
Artrite Reumatoide/imunologia , Senescência Celular/imunologia , Proteínas de Ligação a DNA/imunologia , Desoxirribonucleases/imunologia , Linfócitos T/imunologia , Animais , Células Cultivadas , Dano ao DNA/imunologia , Reparo do DNA/imunologia , Feminino , Humanos , Inflamação/imunologia , Leucócitos Mononucleares/imunologia , Camundongos , Sinovite/imunologia , Telômero/imunologia , Regulação para Cima/imunologia
11.
PLoS Biol ; 20(9): e3001772, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36067248

RESUMO

Potassium ion (K+) plays a critical role as an essential electrolyte in all biological systems. Genetically-encoded fluorescent K+ biosensors are promising tools to further improve our understanding of K+-dependent processes under normal and pathological conditions. Here, we report the crystal structure of a previously reported genetically-encoded fluorescent K+ biosensor, GINKO1, in the K+-bound state. Using structure-guided optimization and directed evolution, we have engineered an improved K+ biosensor, designated GINKO2, with higher sensitivity and specificity. We have demonstrated the utility of GINKO2 for in vivo detection and imaging of K+ dynamics in multiple model organisms, including bacteria, plants, and mice.


Assuntos
Técnicas Biossensoriais , Transferência Ressonante de Energia de Fluorescência , Animais , Técnicas Biossensoriais/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Íons , Camundongos , Potássio
12.
Exp Cell Res ; 438(2): 114061, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38692345

RESUMO

Acute myocardial infarction (AMI) is a prevalent cardiovascular disease with high morbidity and mortality rates worldwide. Pyroptosis is an inflammatory form of programmed cell death that has been linked to various pathological conditions. However, its exact contribution to the onset and progression of heart injury in AMI has not yet fully elucidated. Herein, we established mouse AMI model by ligating the left anterior descending artery and performed transcriptome analysis during the early phase of AMI. Mouse HL-1 and human AC-16 cardiomyocytes were subjected to hypoxia to simulate ischemic injury in vitro. Our results revealed a significant activation of the inflammatory response at 3 h post-ligation, as confirmed by RNA sequencing. We identified the occurrence of NLRP3 inflammasome-mediated pyroptosis in the cardiac tissues of human cases with AMI, as well as in mouse models of AMI and hypoxia-induced cardiomyocytes, using immunohistochemistry staining and Western blotting assays. Concurrently, pharmacological inhibition of NLRP3 inflammasome-mediated pyroptosis with MCC950 and VX-765 effectively decreased hypoxia-induced cardiomyocytes injury, while mitigating myocardial oxidative stress, apoptosis and inflammation caused by hypoxia. Moreover, the circulating levels of gasdermin D (GSDMD), the pyroptosis executor, were remarkably elevated in the plasma of mice with early AMI and in the supernatant of hypoxia-exposed cardiomyocytes in a time-dependent manner using ELISA and Western blotting. Furthermore, the change in circulating GSDMD positively correlated with Creatine Kinase-MB (CK-MB) in the plasma of early-stage AMI mouse. In summary, these findings indicated a critical role for NLRP3 inflammasome-mediated pyroptosis in the progression of AMI, the administration of MCC950 and VX-765 may be attractive candidate therapeutic approaches for cardiac injury caused by acute hypoxia or even AMI. Additionally, the circulating GSDMD exhibits potential as a newly diagnostic biomarker for AMI.


Assuntos
Apoptose , Furanos , Inflamação , Camundongos Endogâmicos C57BL , Infarto do Miocárdio , Miócitos Cardíacos , Estresse Oxidativo , Piroptose , Sulfonamidas , Piroptose/efeitos dos fármacos , Animais , Camundongos , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sulfonamidas/farmacologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Inflamação/tratamento farmacológico , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Masculino , Furanos/farmacologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/tratamento farmacológico , Indenos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , para-Aminobenzoatos/farmacologia , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Modelos Animais de Doenças , Miocárdio/metabolismo , Miocárdio/patologia , Hipóxia/metabolismo , Hipóxia/complicações , Dipeptídeos
13.
Proc Natl Acad Sci U S A ; 119(26): e2119800119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35727989

RESUMO

Phase-separated biomolecular condensates that contain multiple coexisting phases are widespread in vitro and in cells. Multiphase condensates emerge readily within multicomponent mixtures of biomolecules (e.g., proteins and nucleic acids) when the different components present sufficient physicochemical diversity (e.g., in intermolecular forces, structure, and chemical composition) to sustain separate coexisting phases. Because such diversity is highly coupled to the solution conditions (e.g., temperature, pH, salt, composition), it can manifest itself immediately from the nucleation and growth stages of condensate formation, develop spontaneously due to external stimuli or emerge progressively as the condensates age. Here, we investigate thermodynamic factors that can explain the progressive intrinsic transformation of single-component condensates into multiphase architectures during the nonequilibrium process of aging. We develop a multiscale model that integrates atomistic simulations of proteins, sequence-dependent coarse-grained simulations of condensates, and a minimal model of dynamically aging condensates with nonconservative intermolecular forces. Our nonequilibrium simulations of condensate aging predict that single-component condensates that are initially homogeneous and liquid like can transform into gel-core/liquid-shell or liquid-core/gel-shell multiphase condensates as they age due to gradual and irreversible enhancement of interprotein interactions. The type of multiphase architecture is determined by the aging mechanism, the molecular organization of the gel and liquid phases, and the chemical makeup of the protein. Notably, we predict that interprotein disorder to order transitions within the prion-like domains of intracellular proteins can lead to the required nonconservative enhancement of intermolecular interactions. Our study, therefore, predicts a potential mechanism by which the nonequilibrium process of aging results in single-component multiphase condensates.


Assuntos
Envelhecimento , Condensados Biomoleculares , Proteína FUS de Ligação a RNA , Envelhecimento/metabolismo , Condensados Biomoleculares/química , Condensados Biomoleculares/metabolismo , Modelos Biológicos , Simulação de Dinâmica Molecular , Conformação Proteica em Folha beta , Proteína FUS de Ligação a RNA/química , Proteína FUS de Ligação a RNA/metabolismo , Termodinâmica
14.
Eur Heart J ; 45(25): 2235-2250, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38607560

RESUMO

BACKGROUND AND AIMS: Patients with acute myeloid leukaemia (AML) suffer from severe myocardial injury during daunorubicin (DNR)-based chemotherapy and are at high risk of cardiac mortality. The crosstalk between tumour cells and cardiomyocytes might play an important role in chemotherapy-related cardiotoxicity, but this has yet to be demonstrated. This study aimed to identify its underlying mechanism and explore potential therapeutic targets. METHODS: Cardiac tissues were harvested from an AML patient after DNR-based chemotherapy and were subjected to single-nucleus RNA sequencing. Cardiac metabolism and function were evaluated in AML mice after DNR treatment by using positron emission tomography, magnetic resonance imaging, and stable-isotope tracing metabolomics. Plasma cytokines were screened in AML mice after DNR treatment. Genetically modified mice and cell lines were used to validate the central role of the identified cytokine and explore its downstream effectors. RESULTS: In the AML patient, disruption of cardiac metabolic homeostasis was associated with heart dysfunction after DNR-based chemotherapy. In AML mice, cardiac fatty acid utilization was attenuated, resulting in cardiac dysfunction after DNR treatment, but these phenotypes were not observed in similarly treated tumour-free mice. Furthermore, tumour cell-derived interleukin (IL)-1α was identified as a primary factor leading to DNR-induced cardiac dysfunction and administration of an anti-IL-1α neutralizing antibody could improve cardiac functions in AML mice after DNR treatment. CONCLUSIONS: This study revealed that crosstalk between tumour cells and cardiomyocytes during chemotherapy could disturb cardiac energy metabolism and impair heart function. IL-1α neutralizing antibody treatment is a promising strategy for alleviating chemotherapy-induced cardiotoxicity in AML patients.


Assuntos
Daunorrubicina , Interleucina-1alfa , Leucemia Mieloide Aguda , Animais , Leucemia Mieloide Aguda/tratamento farmacológico , Humanos , Interleucina-1alfa/metabolismo , Camundongos , Cardiotoxicidade/etiologia , Antibióticos Antineoplásicos/efeitos adversos , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo
15.
J Infect Dis ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38271258

RESUMO

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS), a lethal tick-borne hemorrhagic fever, prompted our investigation into prognostic predictors and potential drug targets using plasma Olink Proteomics. METHODS: Employing the Olink assay, we analyzed 184 plasma proteins in 30 survivors and 8 non-survivors of SFTS. Validation was performed in a cohort of 154 SFTS patients using enzyme-linked immunosorbent assay. We utilized the Drug Gene Interaction database to identify protein-drug interactions. RESULTS: Non-survivors exhibited 110 differentially expressed proteins (DEPs) compared to survivors, with functional enrichment in the cell chemotaxis-related pathway. Thirteen DEPs, including C-C motif chemokine 20 (CCL20), calcitonin gene-related peptide alpha and Pleiotrophin, were associated with multiple organ dysfunction syndrome. CCL20 emerged as the top predictor of death, demonstrating an area under the curve of 1 (P = .0004) and 0.9033 (P < .0001) in the discovery and validation cohort, respectively. Patients with CCL20 levels exceeding 45.74 pg/mL exhibited a fatality rate of 45.65%, while no deaths occurred in those with lower CCL20 levels. Furthermore, we identified 202 FDA-approved drugs targeting 37 death-related plasma proteins. CONCLUSIONS: Distinct plasma proteomic profiles characterize SFTS patients with different outcomes, with CCL20 emerging as a novel, sensitive, accurate, and specific biomarker for predicting SFTS prognosis.

16.
Biochemistry ; 63(1): 171-180, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38113455

RESUMO

Genetically encoded sensors enable quantitative imaging of analytes in live cells. Sensors are commonly constructed by combining ligand-binding domains with one or more sensitized fluorescent protein (FP) domains. Sensors based on a single FP can be susceptible to artifacts caused by changes in sensor levels or distribution in vivo. To develop intensiometric sensors with the capacity for ratiometric quantification, dual-FP Matryoshka sensors were generated by using a single cassette with a large Stokes shift (LSS) reference FP nested within the reporter FP (cpEGFP). Here, we present a genetically encoded calcium sensor that employs green apple (GA) Matryoshka technology by incorporating a newly designed red LSSmApple fluorophore. LSSmApple matures faster and provides an optimized excitation spectrum overlap with cpEGFP, allowing for monochromatic coexcitation with blue light. The LSS of LSSmApple results in improved emission spectrum separation from cpEGFP, thereby minimizing fluorophore bleed-through and facilitating imaging using standard dichroic and red FP (RFP) emission filters. We developed an image analysis pipeline for yeast (Saccharomyces cerevisiae) timelapse imaging that utilizes LSSmApple to segment and track cells for high-throughput quantitative analysis. In summary, we engineered a new FP, constructed a genetically encoded calcium indicator (GA-MatryoshCaMP6s), and performed calcium imaging in yeast as a demonstration.


Assuntos
Cálcio , Saccharomyces cerevisiae , Proteínas Luminescentes/química , Cálcio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteína Vermelha Fluorescente , Corantes Fluorescentes
17.
Plant J ; 116(3): 717-727, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37632767

RESUMO

Crossovers (COs) are necessary for generating genetic diversity that breeders can select, but there are conserved mechanisms that regulate their frequency and distribution. Increasing CO frequency may raise the efficiency of selection by increasing the chance of integrating more desirable traits. In this study, we characterize rice FANCM and explore its functions in meiotic CO control. FANCM mutations do not affect fertility in rice, but they cause a great boost in the overall frequency of COs in both inbred and hybrid rice, according to genetic analysis of the complete set of fancm zmm (hei10, ptd, shoc1, mer3, zip4, msh4, msh5, and heip1) mutants. Although the early homologous recombination events proceed normally in fancm, the meiotic extra COs are not marked with HEI10 and require MUS81 resolvase for resolution. FANCM depends on PAIR1, COM1, DMC1, and HUS1 to perform its functions. Simultaneous disruption of FANCM and MEICA1 synergistically increases CO frequency, but it is accompanied by nonhomologous chromosome associations and fragmentations. FANCM interacts with the MHF complex, and ablation of rice MHF1 or MHF2 could restore the formation of 12 bivalents in the absence of the ZMM gene ZIP4. Our data indicate that unleashing meiotic COs by mutating any member of the FANCM-MHF complex could be an effective procedure to accelerate the efficiency of rice breeding.


Assuntos
Oryza , Oryza/genética , DNA Helicases/genética , Melhoramento Vegetal , Meiose/genética , Recombinação Homóloga , Troca Genética
18.
Plant Cell Physiol ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38903045

RESUMO

The standout characteristic of the orchid perianth is the transformation of the upper median petal into a distinctively formed lip, which gives orchid flowers their typically zygomorphic symmetry and makes them the most popular ornamental plants worldwide. To study orchid flower development, two WUSCHEL-related homeobox (WOX) genes, PaWOX3 and PaWOX3B, were identified in Phalaenopsis. PaWOX3 and PaWOX3B mRNAs accumulate abundantly during early reproductive development and perianths of young buds, significantly decrease in mature flower and absent in vegetative leaves and roots. PaWOX3 and PaWOX3B virus-induced gene silencing (VIGS) knockdown in Phalaenopsis significantly reduces floral bud numbers, suggesting that PaWOX3/PaWOX3B may be involved in flower initiation. Transgenic Arabidopsis ectopically expressing repressor forms of PaWOX3/PaWOX3B and their Oncidium orthologue, OnPRS, exhibit lateral organ development defects, implicating these genes likely have function in regulating growth and differentiation for lateral organs. Neither PaWOX3, PaWOX3B single nor PaWOX3/PaWOX3B double VIGS Phalaenopsis altered the flower morphology. Interestingly, double silencing of PaWOX3 or PaWOX3B with OAGL6-2, which controlled the identity/formation of lips, altered the symmetry of 'BigLip' produced in OAGL6-2 VIGS. This result indicated that the levels of PaWOX3/PaWOX3B are still sufficient to maintain the symmetry for the OAGL6-2 VIGS 'BigLip'. However, the symmetry of the OAGL6-2 VIGS 'BigLip' can not be maintained once the expression of PaWOX3 or PaWOX3B is further reduced. Thus, in addition to control lip identity, this study further found that OAGL6-2 could cooperate with functionally redundant PaWOX3/PaWOX3B in maintaining the symmetric axis of lip.

19.
Eur J Immunol ; 53(9): e2250324, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37495829

RESUMO

Neutrophils are the most abundant circulating granulocytes, linking innate and adaptive immunity. Neutrophils can regulate inflammatory and immune responses through degranulation, reactive oxygen species generation, the production of cytokines and chemokines, and NETosis. Emerging evidence has indicated that neutrophils contribute to the pathogenesis of various noncancer liver diseases, including nonalcoholic fatty liver disease, alcohol-associated liver disease, hepatic ischemia-reperfusion injury, and liver fibrosis. Cellular interactions among neutrophils, other immune cells, and nonimmune cells constitute a complex network that regulates the immune microenvironment of the liver. This review summarizes novel neutrophil subtypes, including CD177+ neutrophils and low-density neutrophils. Moreover, we provide an overview of the cellular cros stalk of neutrophils in noncancer liver diseases, aiming to shed new light on mechanistic studies of novel neutrophil subtypes. In addition, we discuss the potential of neutrophils as therapeutic targets in noncancer liver diseases, including inhibitors targeting NETosis, granule proteins, and chemokines.


Assuntos
Hepatopatias , Neutrófilos , Humanos , Hepatopatias/terapia , Quimiocinas/metabolismo , Imunidade Adaptativa
20.
Am Heart J ; 269: 131-138, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38128898

RESUMO

BACKGROUND: Nearly 20% Patients with cyanotic congenital heart disease (CCHD) are not able to receive surgery. These patients experience a decline in cardiac function as they age, which has been demonstrated to be associated with changes in energy metabolism in cardiomyocytes. Trimetazidine (TMZ), a metabolic regulator, is supposed to alleviate such maladaptation and reserve cardiac function in CCHD patients. METHODS: This is a randomized, double-blind, placebo-controlled clinical trial. Eighty adult CCHD patients will be recruited and randomized to the TMZ (20 mg TMZ 3 times a day for 3 months) or placebo group (placebo 3 times a day for 3 months). The primary outcome is the difference in cardiac ejection fractions (EF) measured by cardiac magnetic resonance (MRI) between baseline and after 3 months of TMZ treatment. The secondary outcomes include TMZ serum concentration, rate of cardiac events, NYHA grading, fingertip SpO2, NT-proBNP levels, 6-minute walking test (6MWT), KCCQ-CSS questionnaire score, echocardiography, ECG, routine blood examination, liver and kidney function test, blood pressure and heart rate. DISCUSSION: This trial is designed to explore whether the application of TMZ in adult CCHD patients can improve cardiac function, reduce cardiac events, and improve exercise performance and quality of life. The results will provide targeted drug therapy for CCHD patients with hypoxia and support the application of TMZ in children with CCHD.


Assuntos
Doenças Cardiovasculares , Cardiopatias Congênitas , Trimetazidina , Adulto , Criança , Humanos , Trimetazidina/uso terapêutico , Qualidade de Vida , Hipóxia/etiologia , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Método Duplo-Cego , Vasodilatadores/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
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