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1.
Cell ; 187(7): 1719-1732.e14, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38513663

RESUMO

The glycine transporter 1 (GlyT1) plays a crucial role in the regulation of both inhibitory and excitatory neurotransmission by removing glycine from the synaptic cleft. Given its close association with glutamate/glycine co-activated NMDA receptors (NMDARs), GlyT1 has emerged as a central target for the treatment of schizophrenia, which is often linked to hypofunctional NMDARs. Here, we report the cryo-EM structures of GlyT1 bound with substrate glycine and drugs ALX-5407, SSR504734, and PF-03463275. These structures, captured at three fundamental states of the transport cycle-outward-facing, occluded, and inward-facing-enable us to illustrate a comprehensive blueprint of the conformational change associated with glycine reuptake. Additionally, we identified three specific pockets accommodating drugs, providing clear insights into the structural basis of their inhibitory mechanism and selectivity. Collectively, these structures offer significant insights into the transport mechanism and recognition of substrate and anti-schizophrenia drugs, thus providing a platform to design small molecules to treat schizophrenia.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Glicina , Humanos , Transporte Biológico , Glicina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Glicina/química , Proteínas da Membrana Plasmática de Transporte de Glicina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Glicina/ultraestrutura , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/metabolismo , Transmissão Sináptica , Imidazóis/química , Sarcosina/análogos & derivados , Piperidinas/química
2.
Cell ; 186(22): 4788-4802.e15, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37741279

RESUMO

Gravity controls directional growth of plants, and the classical starch-statolith hypothesis proposed more than a century ago postulates that amyloplast sedimentation in specialized cells initiates gravity sensing, but the molecular mechanism remains uncharacterized. The LAZY proteins are known as key regulators of gravitropism, and lazy mutants show striking gravitropic defects. Here, we report that gravistimulation by reorientation triggers mitogen-activated protein kinase (MAPK) signaling-mediated phosphorylation of Arabidopsis LAZY proteins basally polarized in root columella cells. Phosphorylation of LAZY increases its interaction with several translocons at the outer envelope membrane of chloroplasts (TOC) proteins on the surface of amyloplasts, facilitating enrichment of LAZY proteins on amyloplasts. Amyloplast sedimentation subsequently guides LAZY to relocate to the new lower side of the plasma membrane in columella cells, where LAZY induces asymmetrical auxin distribution and root differential growth. Together, this study provides a molecular interpretation for the starch-statolith hypothesis: the organelle-movement-triggered molecular polarity formation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Plastídeos , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Sensação Gravitacional , Raízes de Plantas/metabolismo , Plastídeos/metabolismo , Amido/metabolismo , Proteínas de Membrana/metabolismo
3.
Cell ; 186(15): 3148-3165.e20, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37413990

RESUMO

Chimeric antigen receptor (CAR) T cell therapy effectively treats human cancer, but the loss of the antigen recognized by the CAR poses a major obstacle. We found that in vivo vaccine boosting of CAR T cells triggers the engagement of the endogenous immune system to circumvent antigen-negative tumor escape. Vaccine-boosted CAR T promoted dendritic cell (DC) recruitment to tumors, increased tumor antigen uptake by DCs, and elicited the priming of endogenous anti-tumor T cells. This process was accompanied by shifts in CAR T metabolism toward oxidative phosphorylation (OXPHOS) and was critically dependent on CAR-T-derived IFN-γ. Antigen spreading (AS) induced by vaccine-boosted CAR T enabled a proportion of complete responses even when the initial tumor was 50% CAR antigen negative, and heterogeneous tumor control was further enhanced by the genetic amplification of CAR T IFN-γ expression. Thus, CAR-T-cell-derived IFN-γ plays a critical role in promoting AS, and vaccine boosting provides a clinically translatable strategy to drive such responses against solid tumors.


Assuntos
Vacinas Anticâncer , Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Neoplasias/terapia , Linfócitos T , Imunoterapia Adotiva , Receptores de Antígenos de Linfócitos T/metabolismo
4.
Cell ; 182(3): 713-721.e9, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32778225

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatens global public health. The development of a vaccine is urgently needed for the prevention and control of COVID-19. Here, we report the pilot-scale production of an inactivated SARS-CoV-2 vaccine candidate (BBIBP-CorV) that induces high levels of neutralizing antibodies titers in mice, rats, guinea pigs, rabbits, and nonhuman primates (cynomolgus monkeys and rhesus macaques) to provide protection against SARS-CoV-2. Two-dose immunizations using 2 µg/dose of BBIBP-CorV provided highly efficient protection against SARS-CoV-2 intratracheal challenge in rhesus macaques, without detectable antibody-dependent enhancement of infection. In addition, BBIBP-CorV exhibits efficient productivity and good genetic stability for vaccine manufacture. These results support the further evaluation of BBIBP-CorV in a clinical trial.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Avaliação Pré-Clínica de Medicamentos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas de Produtos Inativados/uso terapêutico , Vacinas Virais/uso terapêutico , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/genética , COVID-19 , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Feminino , Cobaias , Imunogenicidade da Vacina , Macaca fascicularis , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Pneumonia Viral/virologia , Coelhos , Ratos , Ratos Wistar , SARS-CoV-2 , Vacinas de Produtos Inativados/efeitos adversos , Células Vero , Vacinas Virais/efeitos adversos
5.
Immunity ; 57(5): 1087-1104.e7, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38640930

RESUMO

Macrophages are critical to turn noninflamed "cold tumors" into inflamed "hot tumors". Emerging evidence indicates abnormal cholesterol metabolites in the tumor microenvironment (TME) with unclear function. Here, we uncovered the inducible expression of cholesterol-25-hydroxylase (Ch25h) by interleukin-4 (IL-4) and interleukin-13 (IL-13) via the transcription factor STAT6, causing 25-hydroxycholesterol (25HC) accumulation. scRNA-seq analysis confirmed that CH25Hhi subsets were enriched in immunosuppressive macrophage subsets and correlated to lower survival rates in pan-cancers. Targeting CH25H abrogated macrophage immunosuppressive function to enhance infiltrating T cell numbers and activation, which synergized with anti-PD-1 to improve anti-tumor efficacy. Mechanically, lysosome-accumulated 25HC competed with cholesterol for GPR155 binding to inhibit the kinase mTORC1, leading to AMPKα activation and metabolic reprogramming. AMPKα also phosphorylated STAT6 Ser564 to enhance STAT6 activation and ARG1 production. Together, we propose CH25H as an immunometabolic checkpoint, which manipulates macrophage fate to reshape CD8+ T cell surveillance and anti-tumor response.


Assuntos
Hidroxicolesteróis , Lisossomos , Macrófagos , Microambiente Tumoral , Animais , Hidroxicolesteróis/metabolismo , Camundongos , Macrófagos/imunologia , Macrófagos/metabolismo , Humanos , Lisossomos/metabolismo , Microambiente Tumoral/imunologia , Fator de Transcrição STAT6/metabolismo , Adenilato Quinase/metabolismo , Camundongos Endogâmicos C57BL , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Transdução de Sinais , Reprogramação Metabólica
6.
Nat Immunol ; 20(3): 301-312, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30664737

RESUMO

The fetus is thought to be protected from exposure to foreign antigens, yet CD45RO+ T cells reside in the fetal intestine. Here we combined functional assays with mass cytometry, single-cell RNA sequencing and high-throughput T cell antigen receptor (TCR) sequencing to characterize the CD4+ T cell compartment in the human fetal intestine. We identified 22 CD4+ T cell clusters, including naive-like, regulatory-like and memory-like subpopulations, which were confirmed and further characterized at the transcriptional level. Memory-like CD4+ T cells had high expression of Ki-67, indicative of cell division, and CD5, a surrogate marker of TCR avidity, and produced the cytokines IFN-γ and IL-2. Pathway analysis revealed a differentiation trajectory associated with cellular activation and proinflammatory effector functions, and TCR repertoire analysis indicated clonal expansions, distinct repertoire characteristics and interconnections between subpopulations of memory-like CD4+ T cells. Imaging mass cytometry indicated that memory-like CD4+ T cells colocalized with antigen-presenting cells. Collectively, these results provide evidence for the generation of memory-like CD4+ T cells in the human fetal intestine that is consistent with exposure to foreign antigens.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Feto/imunologia , Memória Imunológica/imunologia , Intestinos/imunologia , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD5/genética , Antígenos CD5/imunologia , Antígenos CD5/metabolismo , Células Cultivadas , Feto/citologia , Feto/metabolismo , Citometria de Fluxo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Memória Imunológica/genética , Imunofenotipagem , Intestinos/citologia , Intestinos/embriologia , Antígeno Ki-67/genética , Antígeno Ki-67/imunologia , Antígeno Ki-67/metabolismo
7.
Nature ; 626(7998): 427-434, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081299

RESUMO

Vesicular monoamine transporter 2 (VMAT2) accumulates monoamines in presynaptic vesicles for storage and exocytotic release, and has a vital role in monoaminergic neurotransmission1-3. Dysfunction of monoaminergic systems causes many neurological and psychiatric disorders, including Parkinson's disease, hyperkinetic movement disorders and depression4-6. Suppressing VMAT2 with reserpine and tetrabenazine alleviates symptoms of hypertension and Huntington's disease7,8, respectively. Here we describe cryo-electron microscopy structures of human VMAT2 complexed with serotonin and three clinical drugs at 3.5-2.8 Å, demonstrating the structural basis for transport and inhibition. Reserpine and ketanserin occupy the substrate-binding pocket and lock VMAT2 in cytoplasm-facing and lumen-facing states, respectively, whereas tetrabenazine binds in a VMAT2-specific pocket and traps VMAT2 in an occluded state. The structures in three distinct states also reveal the structural basis of the VMAT2 transport cycle. Our study establishes a structural foundation for the mechanistic understanding of substrate recognition, transport, drug inhibition and pharmacology of VMAT2 while shedding light on the rational design of potential therapeutic agents.


Assuntos
Microscopia Crioeletrônica , Proteínas Vesiculares de Transporte de Monoamina , Humanos , Sítios de Ligação , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Ketanserina/química , Ketanserina/metabolismo , Ketanserina/farmacologia , Reserpina/química , Reserpina/metabolismo , Reserpina/farmacologia , Serotonina/química , Serotonina/metabolismo , Especificidade por Substrato , Tetrabenazina/química , Tetrabenazina/metabolismo , Tetrabenazina/farmacologia , Proteínas Vesiculares de Transporte de Monoamina/antagonistas & inibidores , Proteínas Vesiculares de Transporte de Monoamina/química , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/ultraestrutura
8.
Nature ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112701

RESUMO

The dopamine transporter has a crucial role in regulation of dopaminergic neurotransmission by uptake of dopamine into neurons and contributes to the abuse potential of psychomotor stimulants1-3. Despite decades of study, the structure, substrate binding, conformational transitions and drug-binding poses of human dopamine transporter remain unknown. Here we report structures of the human dopamine transporter in its apo state, and in complex with the substrate dopamine, the attention deficit hyperactivity disorder drug methylphenidate, and the dopamine-uptake inhibitors GBR12909 and benztropine. The dopamine-bound structure in the occluded state precisely illustrates the binding position of dopamine and associated ions. The structures bound to drugs are captured in outward-facing or inward-facing states, illuminating distinct binding modes and conformational transitions during substrate transport. Unlike the outward-facing state, which is stabilized by cocaine, GBR12909 and benztropine stabilize the dopamine transporter in the inward-facing state, revealing previously unseen drug-binding poses and providing insights into how they counteract the effects of cocaine. This study establishes a framework for understanding the functioning of the human dopamine transporter and developing therapeutic interventions for dopamine transporter-related disorders and cocaine addiction.

9.
Nature ; 630(8015): 84-90, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840015

RESUMO

Direct and precise monitoring of intracranial physiology holds immense importance in delineating injuries, prognostication and averting disease1. Wired clinical instruments that use percutaneous leads are accurate but are susceptible to infection, patient mobility constraints and potential surgical complications during removal2. Wireless implantable devices provide greater operational freedom but include issues such as limited detection range, poor degradation and difficulty in size reduction in the human body3. Here we present an injectable, bioresorbable and wireless metastructured hydrogel (metagel) sensor for ultrasonic monitoring of intracranial signals. The metagel sensors are cubes 2 × 2 × 2 mm3 in size that encompass both biodegradable and stimulus-responsive hydrogels and periodically aligned air columns with a specific acoustic reflection spectrum. Implanted into intracranial space with a puncture needle, the metagel deforms in response to physiological environmental changes, causing peak frequency shifts of reflected ultrasound waves that can be wirelessly measured by an external ultrasound probe. The metagel sensor can independently detect intracranial pressure, temperature, pH and flow rate, realize a detection depth of 10 cm and almost fully degrade within 18 weeks. Animal experiments on rats and pigs indicate promising multiparametric sensing performances on a par with conventional non-resorbable wired clinical benchmarks.


Assuntos
Implantes Absorvíveis , Encéfalo , Hidrogéis , Monitorização Fisiológica , Ondas Ultrassônicas , Tecnologia sem Fio , Animais , Masculino , Ratos , Encéfalo/fisiologia , Hidrogéis/química , Concentração de Íons de Hidrogênio , Injeções/instrumentação , Pressão Intracraniana , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Ratos Sprague-Dawley , Porco Miniatura , Temperatura , Fatores de Tempo , Tecnologia sem Fio/instrumentação
10.
Nature ; 631(8022): 826-834, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987597

RESUMO

Glutamate is traditionally viewed as the first messenger to activate NMDAR (N-methyl-D-aspartate receptor)-dependent cell death pathways in stroke1,2, but unsuccessful clinical trials with NMDAR antagonists implicate the engagement of other mechanisms3-7. Here we show that glutamate and its structural analogues, including NMDAR antagonist L-AP5 (also known as APV), robustly potentiate currents mediated by acid-sensing ion channels (ASICs) associated with acidosis-induced neurotoxicity in stroke4. Glutamate increases the affinity of ASICs for protons and their open probability, aggravating ischaemic neurotoxicity in both in vitro and in vivo models. Site-directed mutagenesis, structure-based modelling and functional assays reveal a bona fide glutamate-binding cavity in the extracellular domain of ASIC1a. Computational drug screening identified a small molecule, LK-2, that binds to this cavity and abolishes glutamate-dependent potentiation of ASIC currents but spares NMDARs. LK-2 reduces the infarct volume and improves sensorimotor recovery in a mouse model of ischaemic stroke, reminiscent of that seen in mice with Asic1a knockout or knockout of other cation channels4-7. We conclude that glutamate functions as a positive allosteric modulator for ASICs to exacerbate neurotoxicity, and preferential targeting of the glutamate-binding site on ASICs over that on NMDARs may be strategized for developing stroke therapeutics lacking the psychotic side effects of NMDAR antagonists.


Assuntos
Canais Iônicos Sensíveis a Ácido , Isquemia Encefálica , Ácido Glutâmico , Animais , Feminino , Humanos , Masculino , Camundongos , 2-Amino-5-fosfonovalerato/efeitos adversos , 2-Amino-5-fosfonovalerato/metabolismo , 2-Amino-5-fosfonovalerato/farmacologia , Canais Iônicos Sensíveis a Ácido/química , Canais Iônicos Sensíveis a Ácido/deficiência , Canais Iônicos Sensíveis a Ácido/efeitos dos fármacos , Canais Iônicos Sensíveis a Ácido/genética , Canais Iônicos Sensíveis a Ácido/metabolismo , Regulação Alostérica/efeitos dos fármacos , Sítios de Ligação/genética , Isquemia Encefálica/induzido quimicamente , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Ácido Glutâmico/análogos & derivados , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Ácido Glutâmico/toxicidade , Camundongos Knockout , Mutagênese Sítio-Dirigida , Prótons , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo
11.
Nature ; 621(7979): 602-609, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37704733

RESUMO

Vertebral bone is subject to a distinct set of disease processes from long bones, including a much higher rate of solid tumour metastases1-4. The basis for this distinct biology of vertebral bone has so far remained unknown. Here we identify a vertebral skeletal stem cell (vSSC) that co-expresses ZIC1 and PAX1 together with additional cell surface markers. vSSCs display formal evidence of stemness, including self-renewal, label retention and sitting at the apex of their differentiation hierarchy. vSSCs are physiologic mediators of vertebral bone formation, as genetic blockade of the ability of vSSCs to generate osteoblasts results in defects in the vertebral neural arch and body. Human counterparts of vSSCs can be identified in vertebral endplate specimens and display a conserved differentiation hierarchy and stemness features. Multiple lines of evidence indicate that vSSCs contribute to the high rates of vertebral metastatic tropism observed in breast cancer, owing in part to increased secretion of the novel metastatic trophic factor MFGE8. Together, our results indicate that vSSCs are distinct from other skeletal stem cells and mediate the unique physiology and pathology of vertebrae, including contributing to the high rate of vertebral metastasis.


Assuntos
Neoplasias da Mama , Linhagem da Célula , Metástase Neoplásica , Coluna Vertebral , Células-Tronco , Humanos , Neoplasias da Mama/patologia , Diferenciação Celular , Autorrenovação Celular , Metástase Neoplásica/patologia , Osteoblastos/citologia , Osteoblastos/patologia , Coluna Vertebral/citologia , Coluna Vertebral/patologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Células-Tronco/patologia , Biomarcadores
12.
Nature ; 619(7971): 738-742, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37438533

RESUMO

Scalable generation of genuine multipartite entanglement with an increasing number of qubits is important for both fundamental interest and practical use in quantum-information technologies1,2. On the one hand, multipartite entanglement shows a strong contradiction between the prediction of quantum mechanics and local realization and can be used for the study of quantum-to-classical transition3,4. On the other hand, realizing large-scale entanglement is a benchmark for the quality and controllability of the quantum system and is essential for realizing universal quantum computing5-8. However, scalable generation of genuine multipartite entanglement on a state-of-the-art quantum device can be challenging, requiring accurate quantum gates and efficient verification protocols. Here we show a scalable approach for preparing and verifying intermediate-scale genuine entanglement on a 66-qubit superconducting quantum processor. We used high-fidelity parallel quantum gates and optimized the fidelitites of parallel single- and two-qubit gates to be 99.91% and 99.05%, respectively. With efficient randomized fidelity estimation9, we realized 51-qubit one-dimensional and 30-qubit two-dimensional cluster states and achieved fidelities of 0.637 ± 0.030 and 0.671 ± 0.006, respectively. On the basis of high-fidelity cluster states, we further show a proof-of-principle realization of measurement-based variational quantum eigensolver10 for perturbed planar codes. Our work provides a feasible approach for preparing and verifying entanglement with a few hundred qubits, enabling medium-scale quantum computing with superconducting quantum systems.

13.
EMBO J ; 43(1): 14-31, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177313

RESUMO

Sodium-calcium exchanger proteins influence calcium homeostasis in many cell types and participate in a wide range of physiological and pathological processes. Here, we elucidate the cryo-EM structure of the human Na+/Ca2+ exchanger NCX1.3 in the presence of a specific inhibitor, SEA0400. Conserved ion-coordinating residues are exposed on the cytoplasmic face of NCX1.3, indicating that the observed structure is stabilized in an inward-facing conformation. We show how regulatory calcium-binding domains (CBDs) assemble with the ion-translocation transmembrane domain (TMD). The exchanger-inhibitory peptide (XIP) is trapped within a groove between the TMD and CBD2 and predicted to clash with gating helices TMs1/6 at the outward-facing state, thus hindering conformational transition and promoting inactivation of the transporter. A bound SEA0400 molecule stiffens helix TM2ab and affects conformational rearrangements of TM2ab that are associated with the ion-exchange reaction, thus allosterically attenuating Ca2+-uptake activity of NCX1.3.


Assuntos
Cálcio , Trocador de Sódio e Cálcio , Humanos , Compostos de Anilina/farmacologia , Cálcio/metabolismo , Éteres Fenílicos/farmacologia , Trocador de Sódio e Cálcio/química
14.
EMBO J ; 43(1): 61-86, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177310

RESUMO

Accumulation of DNA damage in the lung induces cellular senescence and promotes age-related diseases such as idiopathic pulmonary fibrosis (IPF). Hence, understanding the mechanistic regulation of DNA damage repair is important for anti-aging therapies and disease control. Here, we identified an m6A-independent role of the RNA-binding protein YTHDC1 in counteracting stress-induced pulmonary senescence and fibrosis. YTHDC1 is primarily expressed in pulmonary alveolar epithelial type 2 (AECII) cells and its AECII expression is significantly decreased in AECIIs during fibrosis. Exogenous overexpression of YTHDC1 alleviates pulmonary senescence and fibrosis independent of its m6A-binding ability, while YTHDC1 deletion enhances disease progression in mice. Mechanistically, YTHDC1 promotes the interaction between TopBP1 and MRE11, thereby activating ATR and facilitating DNA damage repair. These findings reveal a noncanonical function of YTHDC1 in delaying cellular senescence, and suggest that enhancing YTHDC1 expression in the lung could be an effective treatment strategy for pulmonary fibrosis.


Assuntos
Senescência Celular , Fibrose Pulmonar Idiopática , Proteínas do Tecido Nervoso , Fatores de Processamento de RNA , Animais , Camundongos , Envelhecimento/genética , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Fatores de Processamento de RNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo
15.
Proc Natl Acad Sci U S A ; 121(7): e2322375121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315835

RESUMO

Protein S-acyl transferases (PATs) catalyze S-acylation, a reversible post-translational modification critical for membrane association, trafficking, and stability of substrate proteins. Many plant proteins are potentially S-acylated but few have corresponding PATs identified. By using genomic editing, confocal imaging, pharmacological, genetic, and biochemical assays, we demonstrate that three Arabidopsis class C PATs positively regulate BR signaling through S-acylation of BRASSINOSTEROID-SIGNALING KINASE1 (BSK1). PAT19, PAT20, and PAT22 associate with the plasma membrane (PM) and the trans-Golgi network/early endosome (TGN/EE). Functional loss of all three genes results in a plethora of defects, indicative of reduced BR signaling and rescued by enhanced BR signaling. PAT19, PAT20, and PAT22 interact with BSK1 and are critical for the S-acylation of BSK1, and for BR signaling. The PM abundance of BSK1 was reduced by functional loss of PAT19, PAT20, and PAT22 whereas abolished by its S-acylation-deficient point mutations, suggesting a key role of S-acylation in its PM targeting. Finally, an active BR analog induces vacuolar trafficking and degradation of PAT19, PAT20, or PAT22, suggesting that the S-acylation of BSK1 by the three PATs serves as a negative feedback module in BR signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas Serina-Treonina Quinases , Acilação , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas , Transdução de Sinais , Transferases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
16.
N Engl J Med ; 388(15): 1353-1364, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36876740

RESUMO

BACKGROUND: Bempedoic acid, an ATP citrate lyase inhibitor, reduces low-density lipoprotein (LDL) cholesterol levels and is associated with a low incidence of muscle-related adverse events; its effects on cardiovascular outcomes remain uncertain. METHODS: We conducted a double-blind, randomized, placebo-controlled trial involving patients who were unable or unwilling to take statins owing to unacceptable adverse effects ("statin-intolerant" patients) and had, or were at high risk for, cardiovascular disease. The patients were assigned to receive oral bempedoic acid, 180 mg daily, or placebo. The primary end point was a four-component composite of major adverse cardiovascular events, defined as death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization. RESULTS: A total of 13,970 patients underwent randomization; 6992 were assigned to the bempedoic acid group and 6978 to the placebo group. The median duration of follow-up was 40.6 months. The mean LDL cholesterol level at baseline was 139.0 mg per deciliter in both groups, and after 6 months, the reduction in the level was greater with bempedoic acid than with placebo by 29.2 mg per deciliter; the observed difference in the percent reductions was 21.1 percentage points in favor of bempedoic acid. The incidence of a primary end-point event was significantly lower with bempedoic acid than with placebo (819 patients [11.7%] vs. 927 [13.3%]; hazard ratio, 0.87; 95% confidence interval [CI], 0.79 to 0.96; P = 0.004), as were the incidences of a composite of death from cardiovascular causes, nonfatal stroke, or nonfatal myocardial infarction (575 [8.2%] vs. 663 [9.5%]; hazard ratio, 0.85; 95% CI, 0.76 to 0.96; P = 0.006); fatal or nonfatal myocardial infarction (261 [3.7%] vs. 334 [4.8%]; hazard ratio, 0.77; 95% CI, 0.66 to 0.91; P = 0.002); and coronary revascularization (435 [6.2%] vs. 529 [7.6%]; hazard ratio, 0.81; 95% CI, 0.72 to 0.92; P = 0.001). Bempedoic acid had no significant effects on fatal or nonfatal stroke, death from cardiovascular causes, and death from any cause. The incidences of gout and cholelithiasis were higher with bempedoic acid than with placebo (3.1% vs. 2.1% and 2.2% vs. 1.2%, respectively), as were the incidences of small increases in serum creatinine, uric acid, and hepatic-enzyme levels. CONCLUSIONS: Among statin-intolerant patients, treatment with bempedoic acid was associated with a lower risk of major adverse cardiovascular events (death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization). (Funded by Esperion Therapeutics; CLEAR Outcomes ClinicalTrials.gov number, NCT02993406.).


Assuntos
Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/cirurgia , Método Duplo-Cego , Ácidos Graxos/administração & dosagem , Ácidos Graxos/efeitos adversos , Ácidos Graxos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Administração Oral , Revascularização Miocárdica , Hipolipemiantes/administração & dosagem , Hipolipemiantes/efeitos adversos , Hipolipemiantes/uso terapêutico
17.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38670158

RESUMO

Despite the widespread use of ionizable lipid nanoparticles (LNPs) in clinical applications for messenger RNA (mRNA) delivery, the mRNA drug delivery system faces an efficient challenge in the screening of LNPs. Traditional screening methods often require a substantial amount of experimental time and incur high research and development costs. To accelerate the early development stage of LNPs, we propose TransLNP, a transformer-based transfection prediction model designed to aid in the selection of LNPs for mRNA drug delivery systems. TransLNP uses two types of molecular information to perceive the relationship between structure and transfection efficiency: coarse-grained atomic sequence information and fine-grained atomic spatial relationship information. Due to the scarcity of existing LNPs experimental data, we find that pretraining the molecular model is crucial for better understanding the task of predicting LNPs properties, which is achieved through reconstructing atomic 3D coordinates and masking atom predictions. In addition, the issue of data imbalance is particularly prominent in the real-world exploration of LNPs. We introduce the BalMol block to solve this problem by smoothing the distribution of labels and molecular features. Our approach outperforms state-of-the-art works in transfection property prediction under both random and scaffold data splitting. Additionally, we establish a relationship between molecular structural similarity and transfection differences, selecting 4267 pairs of molecular transfection cliffs, which are pairs of molecules that exhibit high structural similarity but significant differences in transfection efficiency, thereby revealing the primary source of prediction errors. The code, model and data are made publicly available at https://github.com/wklix/TransLNP.


Assuntos
Lipídeos , Lipossomos , Nanopartículas , RNA Mensageiro , Nanopartículas/química , RNA Mensageiro/genética , RNA Mensageiro/química , Lipídeos/química , Transfecção , Humanos , Modelos Moleculares , Sistemas de Liberação de Medicamentos
18.
Plant Cell ; 35(3): 1076-1091, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36519262

RESUMO

Grain size is an important agronomic trait, but our knowledge about grain size determination in crops is still limited. Endoplasmic reticulum (ER)-associated degradation (ERAD) is a special ubiquitin proteasome system that is involved in degrading misfolded or incompletely folded proteins in the ER. Here, we report that SMALL GRAIN 3 (SMG3) and DECREASED GRAIN SIZE 1 (DGS1), an ERAD-related E2-E3 enzyme pair, regulate grain size and weight through the brassinosteroid (BR) signaling pathway in rice (Oryza sativa). SMG3 encodes a homolog of Arabidopsis (Arabidopsis thaliana) UBIQUITIN CONJUGATING ENZYME 32, which is a conserved ERAD-associated E2 ubiquitin conjugating enzyme. SMG3 interacts with another grain size regulator, DGS1. Loss of function of SMG3 or DGS1 results in small grains, while overexpression of SMG3 or DGS1 leads to long grains. Further analyses showed that DGS1 is an active E3 ubiquitin ligase and colocates with SMG3 in the ER. SMG3 and DGS1 are involved in BR signaling. DGS1 ubiquitinates the BR receptor BRASSINOSTEROID INSENSITIVE 1 (BRI1) and affects its accumulation. Genetic analysis suggests that SMG3, DGS1, and BRI1 act together to regulate grain size and weight. In summary, our findings identify an ERAD-related E2-E3 pair that regulates grain size and weight, which gives insight into the function of ERAD in grain size control and BR signaling.


Assuntos
Degradação Associada com o Retículo Endoplasmático , Oryza , Enzimas de Conjugação de Ubiquitina , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Degradação Associada com o Retículo Endoplasmático/genética , Oryza/genética , Oryza/metabolismo , Transdução de Sinais , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
19.
Chem Rev ; 124(11): 7262-7378, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38696258

RESUMO

Ligand-protected metal clusters possess hybrid properties that seamlessly combine an inorganic core with an organic ligand shell, imparting them exceptional chemical flexibility and unlocking remarkable application potential in diverse fields. Leveraging chemical flexibility to expand the library of available materials and stimulate the development of new functionalities is becoming an increasingly pressing requirement. This Review focuses on the origin of chemical flexibility from the structural analysis, including intra-cluster bonding, inter-cluster interactions, cluster-environments interactions, metal-to-ligand ratios, and thermodynamic effects. In the introduction, we briefly outline the development of metal clusters and explain the differences and commonalities of M(I)/M(I/0) coinage metal clusters. Additionally, we distinguish the bonding characteristics of metal atoms in the inorganic core, which give rise to their distinct chemical flexibility. Section 2 delves into the structural analysis, bonding categories, and thermodynamic theories related to metal clusters. In the following sections 3 to 7, we primarily elucidate the mechanisms that trigger chemical flexibility, the dynamic processes in transformation, the resultant alterations in structure, and the ensuing modifications in physical-chemical properties. Section 8 presents the notable applications that have emerged from utilizing metal clusters and their assemblies. Finally, in section 9, we discuss future challenges and opportunities within this area.

20.
Nature ; 583(7815): 286-289, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380510

RESUMO

The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health1. The new coronavirus responsible for this outbreak-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG132. Although bats may be the reservoir host for a variety of coronaviruses3,4, it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.


Assuntos
Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Eutérios/virologia , Evolução Molecular , Genoma Viral/genética , Homologia de Sequência do Ácido Nucleico , Animais , Betacoronavirus/classificação , COVID-19 , China , Quirópteros/virologia , Chlorocebus aethiops , Proteínas do Envelope de Coronavírus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Proteínas M de Coronavírus , Proteínas do Nucleocapsídeo de Coronavírus , Reservatórios de Doenças/virologia , Genômica , Especificidade de Hospedeiro , Humanos , Pulmão/patologia , Pulmão/virologia , Malásia , Proteínas do Nucleocapsídeo/genética , Pandemias , Fosfoproteínas , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , Recombinação Genética , SARS-CoV-2 , Alinhamento de Sequência , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/genética , Células Vero , Proteínas do Envelope Viral/genética , Proteínas da Matriz Viral/genética , Zoonoses/transmissão , Zoonoses/virologia
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