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1.
Nat Immunol ; 24(2): 337-348, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36577930

RESUMO

Our previous study using systems vaccinology identified an association between the sterol regulatory binding protein (SREBP) pathway and humoral immune response to vaccination in humans. To investigate the role of SREBP signaling in modulating immune responses, we generated mice with B cell- or CD11c+ antigen-presenting cell (APC)-specific deletion of SCAP, an essential regulator of SREBP signaling. Ablation of SCAP in CD11c+ APCs had no effect on immune responses. In contrast, SREBP signaling in B cells was critical for antibody responses, as well as the generation of germinal centers,memory B cells and bone marrow plasma cells. SREBP signaling was required for metabolic reprogramming in activated B cells. Upon mitogen stimulation, SCAP-deficient B cells could not proliferate and had decreased lipid rafts. Deletion of SCAP in germinal center B cells using AID-Cre decreased lipid raft content and cell cycle progression. These studies provide mechanistic insights coupling sterol metabolism with the quality and longevity of humoral immunity.


Assuntos
Proteínas de Transporte , Linfoma de Células B , Esteróis , Animais , Humanos , Camundongos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Esteróis/metabolismo , Linfoma de Células B/metabolismo
2.
Nat Immunol ; 23(4): 543-555, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35288714

RESUMO

Despite the success of the BNT162b2 mRNA vaccine, the immunological mechanisms that underlie its efficacy are poorly understood. Here we analyzed the innate and adaptive responses to BNT162b2 in mice, and show that immunization stimulated potent antibody and antigen-specific T cell responses, as well as strikingly enhanced innate responses after secondary immunization, which was concurrent with enhanced serum interferon (IFN)-γ levels 1 d following secondary immunization. Notably, we found that natural killer cells and CD8+ T cells in the draining lymph nodes are the major producers of this circulating IFN-γ. Analysis of knockout mice revealed that induction of antibody and T cell responses to BNT162b2 was not dependent on signaling via Toll-like receptors 2, 3, 4, 5 and 7 nor inflammasome activation, nor the necroptosis or pyroptosis cell death pathways. Rather, the CD8+ T cell response induced by BNT162b2 was dependent on type I interferon-dependent MDA5 signaling. These results provide insights into the molecular mechanisms by which the BNT162b2 vaccine stimulates immune responses.


Assuntos
Linfócitos T CD8-Positivos , Vacinas , Imunidade Adaptativa , Animais , Vacina BNT162 , Humanos , Imunidade Inata , Camundongos , Vacinas Sintéticas , Vacinas de mRNA
3.
Nat Immunol ; 21(3): 331-342, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32066950

RESUMO

Germinal center B cells (GCBCs) are critical for generating long-lived humoral immunity. How GCBCs meet the energetic challenge of rapid proliferation is poorly understood. Dividing lymphocytes typically rely on aerobic glycolysis over oxidative phosphorylation for energy. Here we report that GCBCs are exceptional among proliferating B and T cells, as they actively oxidize fatty acids (FAs) and conduct minimal glycolysis. In vitro, GCBCs had a very low glycolytic extracellular acidification rate but consumed oxygen in response to FAs. [13C6]-glucose feeding revealed that GCBCs generate significantly less phosphorylated glucose and little lactate. Further, GCBCs did not metabolize glucose into tricarboxylic acid (TCA) cycle intermediates. Conversely, [13C16]-palmitic acid labeling demonstrated that GCBCs generate most of their acetyl-CoA and acetylcarnitine from FAs. FA oxidation was functionally important, as drug-mediated and genetic dampening of FA oxidation resulted in a selective reduction of GCBCs. Hence, GCBCs appear to uncouple rapid proliferation from aerobic glycolysis.


Assuntos
Linfócitos B/metabolismo , Ácidos Graxos/metabolismo , Centro Germinativo/metabolismo , Animais , Linfócitos B/imunologia , Proliferação de Células , Metabolismo Energético , Ácidos Graxos não Esterificados/metabolismo , Expressão Gênica , Centro Germinativo/citologia , Centro Germinativo/imunologia , Glucose/metabolismo , Glicólise/genética , Técnicas In Vitro , Metaboloma , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Oxirredução , Fosforilação Oxidativa , Consumo de Oxigênio
4.
Nat Immunol ; 20(6): 736-746, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31011187

RESUMO

B cell antigen receptor (BCR) and CD40 signaling are rewired in germinal center (GC) B cells (GCBCs) to optimize selection for high-affinity B cells. In GCBC, BCR signals are constrained, but the mechanisms are not well understood. Here we describe a GC-specific, AKT-kinase-driven negative feedback loop that attenuates BCR signaling. Mass spectrometry revealed that AKT target activity was altered in GCBCs compared with naive B cells. Retargeting was linked to differential AKT T308 and S473 phosphorylation, in turn controlled by GC-specific upregulation of phosphoinositide-dependent protein kinase PDK1 and the phosphatase PTEN. In GCBCs, AKT preferentially targeted CSK, SHP-1 and HPK1, which are negative regulators of BCR signaling. We found that phosphorylation enhances enzymatic activity of these proteins, creating a negative feedback loop that dampens upstream BCR signaling. AKT inhibition relieved this negative feedback and enhanced activation of BCR-proximal kinase LYN, as well as downstream BCR signaling molecules in GCBCs.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Centro Germinativo/imunologia , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Animais , Biomarcadores , Biologia Computacional/métodos , Ativação Enzimática , Técnicas de Inativação de Genes , Humanos , Camundongos Knockout , Fosforilação , Especificidade por Substrato
5.
Cell ; 160(6): 1209-21, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25728666

RESUMO

Rice is sensitive to cold and can be grown only in certain climate zones. Human selection of japonica rice has extended its growth zone to regions with lower temperature, while the molecular basis of this adaptation remains unknown. Here, we identify the quantitative trait locus COLD1 that confers chilling tolerance in japonica rice. Overexpression of COLD1(jap) significantly enhances chilling tolerance, whereas rice lines with deficiency or downregulation of COLD1(jap) are sensitive to cold. COLD1 encodes a regulator of G-protein signaling that localizes on plasma membrane and endoplasmic reticulum (ER). It interacts with the G-protein α subunit to activate the Ca(2+) channel for sensing low temperature and to accelerate G-protein GTPase activity. We further identify that a SNP in COLD1, SNP2, originated from Chinese Oryza rufipogon, is responsible for the ability of COLD(jap/ind) to confer chilling tolerance, supporting the importance of COLD1 in plant adaptation.


Assuntos
Proteínas e Peptídeos de Choque Frio/metabolismo , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Cruzamento , Proteínas e Peptídeos de Choque Frio/genética , Temperatura Baixa , Retículo Endoplasmático , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Mutação , Oryza/citologia , Oryza/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Alinhamento de Sequência
6.
Nat Immunol ; 17(9): 1057-66, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27428826

RESUMO

STING is a central adaptor in the innate immune response to DNA viruses. However, the manner in which STING activity is regulated remains unclear. We identified iRhom2 ('inactive rhomboid protein 2') as a positive regulator of DNA-virus-triggered induction of type I interferons. iRhom2 deficiency markedly impaired DNA-virus- and intracellular-DNA-induced signaling in cells, and iRhom2-deficient mice were more susceptible to lethal herpes simplex virus type 1 (HSV-1) infection. iRhom2 was constitutively associated with STING and acted in two distinct processes to regulate STING activity. iRhom2 recruited the translocon-associated protein TRAPß to the STING complex to facilitate trafficking of STING from the endoplasmic reticulum to perinuclear microsomes. iRhom2 also recruited the deubiquitination enzyme EIF3S5 to maintain the stability of STING through removal of its K48-linked polyubiquitin chains. These results suggest that iRhom2 is essential for STING activity, as it regulates TRAPß-mediated translocation and EIF3S5-mediated deubiquitination of STING.


Assuntos
Proteínas de Transporte/metabolismo , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Proteínas de Membrana/metabolismo , Microssomos/metabolismo , Animais , Proteínas de Transporte/genética , Células Cultivadas , Fator de Iniciação 3 em Eucariotos/metabolismo , Imunidade Inata , Interferon Tipo I/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Estabilidade Proteica , Transporte Proteico/genética , Fosfatase Ácida Resistente a Tartarato/metabolismo , Ubiquitinação
7.
Immunity ; 48(2): 313-326.e5, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29396161

RESUMO

Positive selection of germinal center (GC) B cells is driven by B cell receptor (BCR) affinity and requires help from follicular T helper cells. The transcription factors c-Myc and Foxo1 are critical for GC B cell selection and survival. However, how different affinity-related signaling events control these transcription factors in a manner that links to selection is unknown. Here we showed that GC B cells reprogram CD40 and BCR signaling to transduce via NF-κB and Foxo1, respectively, whereas naive B cells propagate both signals downstream of either receptor. Although either BCR or CD40 ligation induced c-Myc in naive B cells, both signals were required to highly induce c-Myc, a critical mediator of GC B cell survival and cell cycle reentry. Thus, GC B cells rewire their signaling to enhance selection stringency via a requirement for both antigen receptor- and T cell-mediated signals to induce mediators of positive selection.


Assuntos
Antígenos CD40/fisiologia , Centro Germinativo/imunologia , Proteínas Proto-Oncogênicas c-myc/biossíntese , Receptores de Antígenos de Linfócitos B/fisiologia , Transdução de Sinais/fisiologia , Animais , Proteína Forkhead Box O1/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NF-kappa B/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Quinase Syk/fisiologia
8.
Immunity ; 49(3): 438-448.e5, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30193849

RESUMO

Recognition of viral RNA by the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) initiates innate antiviral immune response. How the binding of viral RNA to and activation of the RLRs are regulated remains enigmatic. In this study, we identified ZCCHC3 as a positive regulator of the RLRs including RIG-I and MDA5. ZCCHC3 deficiency markedly inhibited RNA virus-triggered induction of downstream antiviral genes, and ZCCHC3-deficient mice were more susceptible to RNA virus infection. ZCCHC3 was associated with RIG-I and MDA5 and functions in two distinct processes for regulation of RIG-I and MDA5 activities. ZCCHC3 bound to dsRNA and enhanced the binding of RIG-I and MDA5 to dsRNA. ZCCHC3 also recruited the E3 ubiquitin ligase TRIM25 to the RIG-I and MDA5 complexes to facilitate its K63-linked polyubiquitination and activation. Thus, ZCCHC3 is a co-receptor for RIG-I and MDA5, which is critical for RLR-mediated innate immune response to RNA virus.


Assuntos
Proteína DEAD-box 58/metabolismo , Infecções por Vírus de RNA/imunologia , Vírus de RNA/fisiologia , RNA Viral/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Proteínas de Ligação a DNA/metabolismo , Regulação Viral da Expressão Gênica , Células HEK293 , Humanos , Imunidade Inata , Helicase IFIH1 Induzida por Interferon/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , RNA Viral/imunologia , Proteínas de Ligação a RNA/genética , Células THP-1 , Fatores de Transcrição/metabolismo , Ubiquitinação
9.
Nature ; 585(7825): 410-413, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32365354

RESUMO

On 11 March 2020, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic1. The strategies based on non-pharmaceutical interventions that were used to contain the outbreak in China appear to be effective2, but quantitative research is still needed to assess the efficacy of non-pharmaceutical interventions and their timings3. Here, using epidemiological data on COVID-19 and anonymized data on human movement4,5, we develop a modelling framework that uses daily travel networks to simulate different outbreak and intervention scenarios across China. We estimate that there were a total of 114,325 cases of COVID-19 (interquartile range 76,776-164,576) in mainland China as of 29 February 2020. Without non-pharmaceutical interventions, we predict that the number of cases would have been 67-fold higher (interquartile range 44-94-fold) by 29 February 2020, and we find that the effectiveness of different interventions varied. We estimate that early detection and isolation of cases prevented more infections than did travel restrictions and contact reductions, but that a combination of non-pharmaceutical interventions achieved the strongest and most rapid effect. According to our model, the lifting of travel restrictions from 17 February 2020 does not lead to an increase in cases across China if social distancing interventions can be maintained, even at a limited level of an on average 25% reduction in contact between individuals that continues until late April. These findings improve our understanding of the effects of non-pharmaceutical interventions on COVID-19, and will inform response efforts across the world.


Assuntos
Busca de Comunicante/métodos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Desinfecção das Mãos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Quarentena/métodos , Isolamento Social , Viagem/legislação & jurisprudência , COVID-19 , China/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Pneumonia Viral/transmissão , Medição de Risco , Fatores de Tempo
10.
Circ Res ; 132(11): e223-e242, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37154056

RESUMO

BACKGROUND: Doxorubicin is an effective chemotherapy drug for treating various types of cancer. However, lethal cardiotoxicity severely limits its clinical use. Recent evidence has indicated that aberrant activation of the cytosolic DNA-sensing cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)-STING (stimulator of interferon genes) pathway plays a critical role in cardiovascular destruction. Here, we investigate the involvement of this mechanism in doxorubicin-induced cardiotoxicity (DIC). METHODS: Mice were treated with low-dose doxorubicin to induce chronic DIC. The role of the cGAS-STING pathway in DIC was evaluated in cGAS-deficiency (cGAS-/-), Sting-deficiency (Sting-/-), and interferon regulatory factor 3 (Irf3)-deficiency (Irf3-/-) mice. Endothelial cell (EC)-specific conditional Sting deficiency (Stingflox/flox/Cdh5-CreERT) mice were used to assess the importance of this pathway in ECs during DIC. We also examined the direct effects of the cGAS-STING pathway on nicotinamide adenine dinucleotide (NAD) homeostasis in vitro and in vivo. RESULTS: In the chronic DIC model, we observed significant activation of the cGAS-STING pathway in cardiac ECs. Global cGAS, Sting, and Irf3 deficiency all markedly ameliorated DIC. EC-specific Sting deficiency significantly prevented DIC and endothelial dysfunction. Mechanistically, doxorubicin activated the cardiac EC cGAS-STING pathway and its target, IRF3, which directly induced CD38 expression. In cardiac ECs, the cGAS-STING pathway caused a reduction in NAD levels and subsequent mitochondrial dysfunction via the intracellular NAD glycohydrolase (NADase) activity of CD38. Furthermore, the cardiac EC cGAS-STING pathway also regulates NAD homeostasis and mitochondrial bioenergetics in cardiomyocytes through the ecto-NADase activity of CD38. We also demonstrated that pharmacological inhibition of TANK-binding kinase 1 or CD38 effectively ameliorated DIC without compromising the anticancer effects of doxorubicin. CONCLUSIONS: Our findings indicate a critical role of the cardiac EC cGAS-STING pathway in DIC. The cGAS-STING pathway may represent a novel therapeutic target for preventing DIC.


Assuntos
Cardiotoxicidade , Transdução de Sinais , Camundongos , Animais , NAD/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Doxorrubicina/toxicidade
11.
Nature ; 573(7775): 558-562, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31554980

RESUMO

High-pressure transitions are thought to modify hydrogen molecules to a molecular metallic solid and finally to an atomic metal1, which is predicted to have exotic physical properties and the topology of a two-component (electron and proton) superconducting superfluid condensate2,3. Therefore, understanding such transitions remains an important objective in condensed matter physics4,5. However, measurements of the crystal structure of solid hydrogen, which provides crucial information about the metallization of hydrogen under compression, are lacking for most high-pressure phases, owing to the considerable technical challenges involved in X-ray and neutron diffraction measurements under extreme conditions. Here we present a single-crystal X-ray diffraction study of solid hydrogen at pressures of up to 254 gigapascals that reveals the crystallographic nature of the transitions from phase I to phases III and IV. Under compression, hydrogen molecules remain in the hexagonal close-packed (hcp) crystal lattice structure, accompanied by a monotonic increase in anisotropy. In addition, the pressure-dependent decrease of the unit cell volume exhibits a slope change when entering phase IV, suggesting a second-order isostructural phase transition. Our results indicate that the precursor to the exotic two-component atomic hydrogen may consist of electronic transitions caused by a highly distorted hcp Brillouin zone and molecular-symmetry breaking.


Assuntos
Hidrogênio/química , Modelos Moleculares , Pressão , Eletrônica , Difração de Nêutrons , Transição de Fase , Difração de Raios X
12.
Nucleic Acids Res ; 51(11): 5414-5431, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37021556

RESUMO

Cellular totipotency is critical for whole-organism generation, yet how totipotency is established remains poorly illustrated. Abundant transposable elements (TEs) are activated in totipotent cells, which is critical for embryonic totipotency. Here, we show that the histone chaperone RBBP4, but not its homolog RBBP7, is indispensable for maintaining the identity of mouse embryonic stem cells (mESCs). Auxin-induced degradation of RBBP4, but not RBBP7, reprograms mESCs to the totipotent 2C-like cells. Also, loss of RBBP4 enhances transition from mESCs to trophoblast cells. Mechanistically, RBBP4 binds to the endogenous retroviruses (ERVs) and functions as an upstream regulator by recruiting G9a to deposit H3K9me2 on ERVL elements, and recruiting KAP1 to deposit H3K9me3 on ERV1/ERVK elements, respectively. Moreover, RBBP4 facilitates the maintenance of nucleosome occupancy at the ERVK and ERVL sites within heterochromatin regions through the chromatin remodeler CHD4. RBBP4 depletion leads to the loss of the heterochromatin marks and activation of TEs and 2C genes. Together, our findings illustrate that RBBP4 is required for heterochromatin assembly and is a critical barrier for inducing cell fate transition from pluripotency to totipotency.


Assuntos
Heterocromatina , Células-Tronco Pluripotentes , Animais , Camundongos , Heterocromatina/genética , Heterocromatina/metabolismo , Fatores de Transcrição/metabolismo , Cromatina/metabolismo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Epigênese Genética
13.
Eur Heart J ; 45(9): 669-684, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085922

RESUMO

BACKGROUND AND AIMS: Survivors of acute coronary syndromes face an elevated risk of recurrent atherosclerosis-related vascular events despite advanced medical treatments. The underlying causes remain unclear. This study aims to investigate whether myocardial infarction (MI)-induced trained immunity in monocytes could sustain proatherogenic traits and expedite atherosclerosis. METHODS: Apolipoprotein-E deficient (ApoE-/-) mice and adoptive bone marrow transfer chimeric mice underwent MI or myocardial ischaemia-reperfusion (IR). A subsequent 12-week high-fat diet (HFD) regimen was implemented to elucidate the mechanism behind monocyte trained immunity. In addition, classical monocytes were analysed by flow cytometry in the blood of enrolled patients. RESULTS: In MI and IR mice, blood monocytes and bone marrow-derived macrophages exhibited elevated spleen tyrosine kinase (SYK), lysine methyltransferase 5A (KMT5A), and CCHC-type zinc finger nucleic acid-binding protein (CNBP) expression upon exposure to a HFD or oxidized LDL (oxLDL) stimulation. MI-induced trained immunity was transmissible by transplantation of bone marrow to accelerate atherosclerosis in naive recipients. KMT5A specifically recruited monomethylation of Lys20 of histone H4 (H4K20me) to the gene body of SYK and synergistically transactivated SYK with CNBP. In vivo small interfering RNA (siRNA) inhibition of KMT5A or CNBP potentially slowed post-MI atherosclerosis. Sympathetic denervation with 6-hydroxydopamine reduced atherosclerosis and inflammation after MI. Classical monocytes from ST-elevation MI (STEMI) patients with advanced coronary lesions expressed higher SYK and KMT5A gene levels. CONCLUSIONS: The findings underscore the crucial role of monocyte trained immunity in accelerated atherosclerosis after MI, implying that SYK in blood classical monocytes may serve as a predictive factor for the progression of atherosclerosis in STEMI patients.


Assuntos
Aterosclerose , Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Animais , Camundongos , Monócitos , Imunidade Treinada
14.
BMC Biol ; 22(1): 111, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741075

RESUMO

BACKGROUND: Juvenile hormones (JH) play crucial role in regulating development and reproduction in insects. The most common form of JH is JH III, derived from MF through epoxidation by CYP15 enzymes. However, in the higher dipterans, such as the fruitfly, Drosophila melanogaster, a bis-epoxide form of JHB3, accounted most of the JH detected. Moreover, these higher dipterans have lost the CYP15 gene from their genomes. As a result, the identity of the P450 epoxidase in the JH biosynthesis pathway in higher dipterans remains unknown. RESULTS: In this study, we show that Cyp6g2 serves as the major JH epoxidase responsible for the biosynthesis of JHB3 and JH III in D. melanogaster. The Cyp6g2 is predominantly expressed in the corpus allatum (CA), concurring with the expression pattern of jhamt, another well-studied gene that is crucial in the last steps of JH biosynthesis. Mutation in Cyp6g2 leads to severe disruptions in larval-pupal metamorphosis and exhibits reproductive deficiencies, exceeding those seen in jhamt mutants. Notably, Cyp6g2-/-::jhamt2 double mutants all died at the pupal stage but could be rescued through the topical application of JH analogs. JH titer analyses revealed that both Cyp6g2-/- mutant and jhamt2 mutant lacking JHB3 and JH III, while overexpression of Cyp6g2 or jhamt caused a significant increase in JHB3 and JH III titer. CONCLUSIONS: These findings collectively established that Cyp6g2 as the major JH epoxidase in the higher dipterans and laid the groundwork for the further understanding of JH biosynthesis. Moreover, these findings pave the way for developing specific Cyp6g2 inhibitors as insect growth regulators or insecticides.


Assuntos
Sistema Enzimático do Citocromo P-450 , Drosophila melanogaster , Hormônios Juvenis , Animais , Corpora Allata/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Hormônios Juvenis/biossíntese , Hormônios Juvenis/metabolismo , Larva/crescimento & desenvolvimento , Larva/genética , Metamorfose Biológica/genética , Oxirredutases , Pupa/crescimento & desenvolvimento , Pupa/genética , Pupa/metabolismo
15.
Nano Lett ; 24(20): 5958-5967, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38738749

RESUMO

Micro/nanorobots hold the potential to revolutionize biomedicine by executing diverse tasks in hard-to-reach biological environments. Nevertheless, achieving precise drug delivery to unknown disease sites using swarming micro/nanorobots remains a significant challenge. Here we develop a heterogeneous swarm comprising sensing microrobots (sensor-bots) and drug-carrying microrobots (carrier-bots) with collaborative tasking capabilities for precise drug delivery toward unknown sites. Leveraging robust interspecific hydrodynamic interactions, the sensor-bots and carrier-bots spontaneously synchronize and self-organize into stable heterogeneous microswarms. Given that the sensor-bots can create real-time pH maps employing pH-responsive structural-color changes and the doxorubicin-loaded carrier-bots exhibit selective adhesion to acidic targets via pH-responsive charge reversal, the sensor-carrier microswarm, when exploring unknown environments, can detect and localize uncharted acidic targets, guide itself to cover the area, and finally deploy therapeutic carrier-bots precisely there. This versatile platform holds promise for treating diseases with localized acidosis and inspires future theranostic microsystems with expandability, task flexibility, and high efficiency.


Assuntos
Doxorrubicina , Sistemas de Liberação de Medicamentos , Doxorrubicina/química , Doxorrubicina/farmacologia , Concentração de Íons de Hidrogênio , Acidose , Humanos , Portadores de Fármacos/química , Robótica
16.
Circulation ; 148(12): 959-977, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37555319

RESUMO

BACKGROUND: Smooth muscle cell (SMC) phenotypic switching has been increasingly detected in aortic aneurysm and dissection (AAD) tissues. However, the diverse SMC phenotypes in AAD tissues and the mechanisms driving SMC phenotypic alterations remain to be identified. METHODS: We examined the transcriptomic and epigenomic dynamics of aortic SMC phenotypic changes in mice with angiotensin II-induced AAD by using single-cell RNA sequencing and single-cell sequencing assay for transposase-accessible chromatin. SMC phenotypic alteration in aortas from patients with ascending thoracic AAD was examined by using single-cell RNA sequencing analysis. RESULTS: Single-cell RNA sequencing analysis revealed that aortic stress induced the transition of SMCs from a primary contractile phenotype to proliferative, extracellular matrix-producing, and inflammatory phenotypes. Lineage tracing showed the complete transformation of SMCs to fibroblasts and macrophages. Single-cell sequencing assay for transposase-accessible chromatin analysis indicated that these phenotypic alterations were controlled by chromatin remodeling marked by the reduced chromatin accessibility of contractile genes and the induced chromatin accessibility of genes involved in proliferation, extracellular matrix, and inflammation. IRF3 (interferon regulatory factor 3), a proinflammatory transcription factor activated by cytosolic DNA, was identified as a key driver of the transition of aortic SMCs from a contractile phenotype to an inflammatory phenotype. In cultured SMCs, cytosolic DNA signaled through its sensor STING (stimulator of interferon genes)-TBK1 (tank-binding kinase 1) to activate IRF3, which bound and recruited EZH2 (enhancer of zeste homolog 2) to contractile genes to induce repressive H3K27me3 modification and gene suppression. In contrast, double-stranded DNA-STING-IRF3 signaling induced inflammatory gene expression in SMCs. In Sting-/- mice, the aortic stress-induced transition of SMCs into an inflammatory phenotype was prevented, and SMC populations were preserved. Finally, profound SMC phenotypic alterations toward diverse directions were detected in human ascending thoracic AAD tissues. CONCLUSIONS: Our study reveals the dynamic epigenetic induction of SMC phenotypic alterations in AAD. DNA damage and cytosolic leakage drive SMCs from a contractile phenotype to an inflammatory phenotype.


Assuntos
Aneurisma da Aorta Torácica , Aneurisma Aórtico , Dissecção Aórtica , Humanos , Camundongos , Animais , Epigenômica , Fenótipo , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/metabolismo , Dissecção Aórtica/genética , Miócitos de Músculo Liso/metabolismo , DNA/metabolismo , Cromatina/metabolismo , Epigênese Genética , Células Cultivadas
17.
BMC Genomics ; 25(1): 514, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789922

RESUMO

BACKGROUND: In aquaculture, sturgeons are generally maintained in the confined spaces, which not only hinders sturgeon movement, but also threatens their flesh quality that seriously concerned by aquaculture industry. As a typical antioxidant, resveratrol can improve the flesh quality of livestock and poultry. However, the mechanism of resveratrol's effect on the muscle of Siberian sturgeon is still unclear. RESULTS: In this study, the dietary resveratrol increased the myofiber diameter, the content of the amino acids, antioxidant capacity markers (CAT, LDH and SOD) levels and the expression levels of mTORC1 and MYH9 in muscle of Siberian sturgeon. Further transcriptome analysis displayed that ROS production-related pathways ("Oxidative phosphorylation" and "Chemical carcinogenes-reactive oxygen species") were enriched in KEGG analysis, and the expression levels of genes related to the production of ROS (COX4, COX6A, ATPeF1A, etc.) in mitochondria were significantly down-regulated, while the expression levels of genes related to scavenging ROS (SOD1) were up-regulated. CONCLUSIONS: In summary, this study reveals that resveratrol may promote the flesh quality of Siberian sturgeon probably by enhancing myofiber growth, nutritional value and the antioxidant capacity of muscle, which has certain reference significance for the development of a new type of feed for Siberian sturgeon.


Assuntos
Antioxidantes , Peixes , Resveratrol , Animais , Resveratrol/farmacologia , Peixes/metabolismo , Peixes/crescimento & desenvolvimento , Peixes/genética , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Nutrientes/metabolismo , Ração Animal/análise , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/citologia , Cadeias Pesadas de Miosina/metabolismo , Cadeias Pesadas de Miosina/genética , Dieta/veterinária , Perfilação da Expressão Gênica
18.
Br J Cancer ; 130(7): 1109-1118, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341511

RESUMO

BACKGROUND: 13-15% of breast cancer/BC patients diagnosed as pathological complete response/pCR after neoadjuvant systemic therapy/NST suffer from recurrence. This study aims to estimate the rationality of organoid forming potential/OFP for more accurate evaluation of NST efficacy. METHODS: OFPs of post-NST residual disease/RD were checked and compared with clinical approaches to estimate the recurrence risk. The phenotypes of organoids were classified via HE staining and ER, PR, HER2, Ki67 and CD133 immuno-labeling. The active growing organoids were subjected to drug sensitivity tests. RESULTS: Of 62 post-NST BC specimens, 24 were classified as OFP-I with long-term active organoid growth, 19 as OFP-II with stable organoid growth within 3 weeks, and 19 as OFP-III without organoid formation. Residual tumors were overall correlated with OFP grades (P < 0.001), while 3 of the 18 patients (16.67%) pathologically diagnosed as tumor-free (ypT0N0M0) showed tumor derived-organoid formation. The disease-free survival/DFS of OFP-I cases was worse than other two groups (Log-rank P < 0.05). Organoids of OFP-I/-II groups well maintained the biological features of their parental tumors and were resistant to the drugs used in NST. CONCLUSIONS: The OFP would be a complementary parameter to improve the evaluation accuracy of NST efficacy of breast cancers.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Intervalo Livre de Doença , Receptor ErbB-2 , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
19.
Clin Immunol ; 258: 109860, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38065369

RESUMO

Pathogens commonly enter mucosal barrier tissues and tissue-resident memory T cells (TRM) are essential for preventing mucosal lesions. However, the immunological properties of TRM cells in nasal mucosa are poorly known. In comparison with control tissues, decreasing CD103+ TRM cells were observed in Chronic rhinosinusitis with nasal polyps (CRSwNPs) and sinonasal inverted papilloma (SNIP), which presented high capability to produce effector cytokines. In CRSwNPs, we found that CD103+ TRM cells with higher cytokine and Granzyme B coexpressed high PD-1, CD103- TRM cells expressed higher IL-10. Homogenates isolated from CRSwNPs induced CD103 expression on peripheral T cells which could be inhibited by blocking TGF-ß. The frequencies of CD103+ TRM cells in CRSwNPs were extremely negatively correlated with neutrophil infiltration. CD103+ TRM cells from Staphylococcus aureus positive CRSwNPs had a stronger response to SEB. Taken together, two phenotypically and functionally distinct subsets of TRM cells exist in nasal tissues and play critical roles in the progress of CRSwNPs and SNIPs.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Células T de Memória , Memória Imunológica , Citocinas/metabolismo , Mucosa Nasal/metabolismo
20.
BMC Plant Biol ; 24(1): 333, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664694

RESUMO

BACKGROUND: The circadian clock, also known as the circadian rhythm, is responsible for predicting daily and seasonal changes in the environment, and adjusting various physiological and developmental processes to the appropriate times during plant growth and development. The circadian clock controls the expression of the Lhcb gene, which encodes the chlorophyll a/b binding protein. However, the roles of the Lhcb gene in tea plant remain unclear. RESULTS: In this study, a total of 16 CsLhcb genes were identified based on the tea plant genome, which were distributed on 8 chromosomes of the tea plant. The promoter regions of CsLhcb genes have a variety of cis-acting elements including hormonal, abiotic stress responses and light response elements. The CsLhcb family genes are involved in the light response process in tea plant. The photosynthetic parameter of tea leaves showed rhythmic changes during the two photoperiod periods (48 h). Stomata are basically open during the day and closed at night. Real-time quantitative PCR results showed that most of the CsLhcb family genes were highly expressed during the day, but were less expressed at night. CONCLUSIONS: Results indicated that CsLhcb genes were involved in the circadian clock process of tea plant, it also provided potential references for further understanding of the function of CsLhcb gene family in tea plant.


Assuntos
Camellia sinensis , Ritmo Circadiano , Fotossíntese , Fotossíntese/genética , Camellia sinensis/genética , Camellia sinensis/fisiologia , Ritmo Circadiano/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas , Família Multigênica , Proteínas de Ligação à Clorofila/genética , Proteínas de Ligação à Clorofila/metabolismo , Fotoperíodo
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