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1.
Cell ; 187(7): 1651-1665.e21, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38490195

RESUMEN

The immune checkpoint blockade (ICB) response in human cancers is closely linked to the gut microbiota. Here, we report that the abundance of commensal Lactobacillus johnsonii is positively correlated with the responsiveness of ICB. Supplementation with Lactobacillus johnsonii or tryptophan-derived metabolite indole-3-propionic acid (IPA) enhances the efficacy of CD8+ T cell-mediated αPD-1 immunotherapy. Mechanistically, Lactobacillus johnsonii collaborates with Clostridium sporogenes to produce IPA. IPA modulates the stemness program of CD8+ T cells and facilitates the generation of progenitor exhausted CD8+ T cells (Tpex) by increasing H3K27 acetylation at the super-enhancer region of Tcf7. IPA improves ICB responsiveness at the pan-cancer level, including melanoma, breast cancer, and colorectal cancer. Collectively, our findings identify a microbial metabolite-immune regulatory pathway and suggest a potential microbial-based adjuvant approach to improve the responsiveness of immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos , Inmunoterapia , Lactobacillus , Neoplasias , Humanos , Lactobacillus/metabolismo , Neoplasias/inmunología , Neoplasias/terapia , Indoles/metabolismo , Inhibidores de Puntos de Control Inmunológico/uso terapéutico
2.
Cell ; 185(1): 95-112.e18, 2022 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-34995520

RESUMEN

Fingerprints are of long-standing practical and cultural interest, but little is known about the mechanisms that underlie their variation. Using genome-wide scans in Han Chinese cohorts, we identified 18 loci associated with fingerprint type across the digits, including a genetic basis for the long-recognized "pattern-block" correlations among the middle three digits. In particular, we identified a variant near EVI1 that alters regulatory activity and established a role for EVI1 in dermatoglyph patterning in mice. Dynamic EVI1 expression during human development supports its role in shaping the limbs and digits, rather than influencing skin patterning directly. Trans-ethnic meta-analysis identified 43 fingerprint-associated loci, with nearby genes being strongly enriched for general limb development pathways. We also found that fingerprint patterns were genetically correlated with hand proportions. Taken together, these findings support the key role of limb development genes in influencing the outcome of fingerprint patterning.


Asunto(s)
Dermatoglifia , Dedos/crecimiento & desarrollo , Organogénesis/genética , Polimorfismo de Nucleótido Simple , Dedos del Pie/crecimiento & desarrollo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Pueblo Asiatico/genética , Tipificación del Cuerpo/genética , Niño , Estudios de Cohortes , Femenino , Miembro Anterior/crecimiento & desarrollo , Sitios Genéticos , Estudio de Asociación del Genoma Completo , Humanos , Proteína del Locus del Complejo MDS1 y EV11/genética , Masculino , Ratones , Persona de Mediana Edad , Adulto Joven
3.
Annu Rev Cell Dev Biol ; 36: 141-164, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-32886535

RESUMEN

Mitochondrial function depends on the efficient import of proteins synthesized in the cytosol. When cells experience stress, the efficiency and faithfulness of the mitochondrial protein import machinery are compromised, leading to homeostatic imbalances and damage to the organelle. Yeast Msp1 (mitochondrial sorting of proteins 1) and mammalian ATAD1 (ATPase family AAA domain-containing 1) are orthologous AAA proteins that, fueled by ATP hydrolysis, recognize and extract mislocalized membrane proteins from the outer mitochondrial membrane. Msp1 also extracts proteins that have become stuck in the import channel. The extracted proteins are targeted for proteasome-dependent degradation or, in the case of mistargeted tail-anchored proteins, are given another chance to be routed correctly. In addition, ATAD1 is implicated in the regulation of synaptic plasticity, mediating the release of neurotransmitter receptors from postsynaptic scaffolds to allow their trafficking. Here we discuss how structural and functional specialization imparts the unique properties that allow Msp1/ATAD1 ATPases to fulfill these diverse functions and also highlight outstanding questions in the field.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Sinapsis/metabolismo , Animales , Humanos , Mitocondrias/metabolismo , Proteínas Mitocondriales/química , Proteínas Mitocondriales/metabolismo , Modelos Moleculares
4.
Proc Natl Acad Sci U S A ; 121(8): e2306936121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38349873

RESUMEN

Accumulating evidence suggests that the brain renin angiotensin system (RAS) plays a pivotal role in the regulation of cognition and behavior as well as in the neuropathology of neurological and mental disorders. The angiotensin II type 1 receptor (AT1R) mediates most functional and neuropathology-relevant actions associated with the central RAS. However, an overarching comprehension to guide translation and utilize the therapeutic potential of the central RAS in humans is currently lacking. We conducted a comprehensive characterization of the RAS using an innovative combination of transcriptomic gene expression mapping, image-based behavioral decoding, and pre-registered randomized controlled discovery-replication pharmacological resting-state functional magnetic resonance imaging (fMRI) trials (N = 132) with a selective AT1R antagonist. The AT1R exhibited a particular dense expression in a subcortical network encompassing the thalamus, striatum, and amygdalo-hippocampal formation. Behavioral decoding of the AT1R gene expression brain map showed an association with memory, stress, reward, and motivational processes. Transient pharmacological blockade of the AT1R further decreased neural activity in subcortical systems characterized by a high AT1R expression, while increasing functional connectivity in the cortico-basal ganglia-thalamo-cortical circuitry. Effects of AT1R blockade on the network level were specifically associated with the transcriptomic signatures of the dopaminergic, opioid, acetylcholine, and corticotropin-releasing hormone signaling systems. The robustness of the results was supported in an independent pharmacological fMRI trial. These findings present a biologically informed comprehensive characterization of the central AT1R pathways and their functional relevance on the neural and behavioral level in humans.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II , Sistema Renina-Angiotensina , Humanos , Sistema Renina-Angiotensina/genética , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Transducción de Señal , Presión Sanguínea , Perfilación de la Expresión Génica , Receptor de Angiotensina Tipo 1/genética , Angiotensina II/metabolismo
5.
Plant Cell ; 35(4): 1186-1201, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36625683

RESUMEN

Elicitins are a large family of secreted proteins in Phytophthora. Clade 1 elicitins were identified decades ago as potent elicitors of immune responses in Nicotiana species, but the mechanisms underlying elicitin recognition are largely unknown. Here we identified an elicitin receptor in Nicotiana benthamiana that we named REL for Responsive to ELicitins. REL is a receptor-like protein (RLP) with an extracellular leucine-rich repeat (LRR) domain that mediates Phytophthora resistance by binding elicitins. Silencing or knocking out REL in N. benthamiana abolished elicitin-triggered cell death and immune responses. Domain deletion and site-directed mutagenesis revealed that the island domain (ID) located within the LRR domain of REL is crucial for elicitin recognition. In addition, sequence polymorphism in the ID underpins the genetic diversity of REL homologs in various Nicotiana species in elicitin recognition and binding. Remarkably, REL is phylogenetically distant from the elicitin response (ELR) protein, an LRR-RLP that was previously identified in the wild potato species Solanum microdontum and REL and ELR differ in the way they bind and recognize elicitins. Our findings provide insights into the molecular basis of plant innate immunity and highlight a convergent evolution of immune receptors towards perceiving the same elicitor.


Asunto(s)
Phytophthora , Solanum , Proteínas/metabolismo , Plantas/metabolismo , Phytophthora/genética , Phytophthora/metabolismo , Nicotiana/metabolismo , Solanum/metabolismo , Enfermedades de las Plantas
6.
Nat Chem Biol ; 20(4): 422-431, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37945896

RESUMEN

The integrated stress response (ISR) enables cells to survive a variety of acute stresses, but chronic activation of the ISR underlies age-related diseases. ISR signaling downregulates translation and activates expression of stress-responsive factors that promote return to homeostasis and is initiated by inhibition of the decameric guanine nucleotide exchange factor eIF2B. Conformational and assembly transitions regulate eIF2B activity, but the allosteric mechanisms controlling these dynamic transitions and mediating the therapeutic effects of the small-molecule ISR inhibitor ISRIB are unknown. Using hydrogen-deuterium exchange-mass spectrometry and cryo-electron microscopy, we identified a central α-helix whose orientation allosterically coordinates eIF2B conformation and assembly. Biochemical and cellular signaling assays show that this 'switch-helix' controls eIF2B activity and signaling. In sum, the switch-helix acts as a fulcrum of eIF2B conformational regulation and is a highly conserved actuator of ISR signal transduction. This work uncovers a conserved allosteric mechanism and unlocks new therapeutic possibilities for ISR-linked diseases.


Asunto(s)
Factor 2B Eucariótico de Iniciación , Factores de Intercambio de Guanina Nucleótido , Factor 2B Eucariótico de Iniciación/química , Factor 2B Eucariótico de Iniciación/metabolismo , Regulación Alostérica , Microscopía por Crioelectrón , Factores de Intercambio de Guanina Nucleótido/metabolismo , Transducción de Señal , Fosforilación
7.
Nature ; 584(7819): 120-124, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32454512

RESUMEN

An outbreak of coronavirus disease 2019 (COVID-19)1-3, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)4, has spread globally. Countermeasures are needed to treat and prevent further dissemination of the virus. Here we report the isolation of two specific human monoclonal antibodies (termed CA1 and CB6) from a patient convalescing from COVID-19. CA1 and CB6 demonstrated potent SARS-CoV-2-specific neutralization activity in vitro. In addition, CB6 inhibited infection with SARS-CoV-2 in rhesus monkeys in both prophylactic and treatment settings. We also performed structural studies, which revealed that CB6 recognizes an epitope that overlaps with angiotensin-converting enzyme 2 (ACE2)-binding sites in the SARS-CoV-2 receptor-binding domain, and thereby interferes with virus-receptor interactions by both steric hindrance and direct competition for interface residues. Our results suggest that CB6 deserves further study as a candidate for translation to the clinic.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/virología , Neumonía Viral/inmunología , Neumonía Viral/virología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Enzima Convertidora de Angiotensina 2 , Animales , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/farmacología , Anticuerpos Antivirales/química , Anticuerpos Antivirales/farmacología , Betacoronavirus/química , Unión Competitiva , COVID-19 , Línea Celular , Chlorocebus aethiops , Cristalización , Cristalografía por Rayos X , Femenino , Humanos , Técnicas In Vitro , Macaca mulatta/inmunología , Macaca mulatta/virología , Masculino , Modelos Moleculares , Pruebas de Neutralización , Pandemias , Peptidil-Dipeptidasa A/química , Peptidil-Dipeptidasa A/metabolismo , Unión Proteica/efectos de los fármacos , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/antagonistas & inhibidores , Glicoproteína de la Espiga del Coronavirus/metabolismo , Células Vero , Carga Viral/inmunología
8.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38197310

RESUMEN

Network pharmacology (NP) provides a new methodological perspective for understanding traditional medicine from a holistic perspective, giving rise to frontiers such as traditional Chinese medicine network pharmacology (TCM-NP). With the development of artificial intelligence (AI) technology, it is key for NP to develop network-based AI methods to reveal the treatment mechanism of complex diseases from massive omics data. In this review, focusing on the TCM-NP, we summarize involved AI methods into three categories: network relationship mining, network target positioning and network target navigating, and present the typical application of TCM-NP in uncovering biological basis and clinical value of Cold/Hot syndromes. Collectively, our review provides researchers with an innovative overview of the methodological progress of NP and its application in TCM from the AI perspective.


Asunto(s)
Inteligencia Artificial , Medicina Tradicional China , Humanos , Farmacología en Red , Investigadores
9.
Am J Pathol ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38849030

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease characterized by pulmonary fibroblast overactivation, resulting in the accumulation of abnormal extracellular matrix and lung parenchymal damage. Although the pathogenesis of IPF remains unclear, aging was proposed as the most prominent nongenetic risk factor. Previous studies have indicated that propionate metabolism undergoes reprogramming in the aging population, leading to the accumulation of the by-product methylmalonic acid (MMA). This study aims to explore alterations in propionate metabolism in IPF and the impact of the by-product MMA on pulmonary fibrosis. The present study revealed alterations in the expression of enzymes involved in propionate metabolism within IPF lung tissues, characterized by an increase in propionyl-CoA carboxylase and methylmalonyl-CoA epimerase expression, and a decrease in methylmalonyl-CoA mutase expression. Knockdown of methylmalonyl-CoA mutase, the key enzyme in propionate metabolism, in A549 cells induced a profibrotic phenotype and activated co-cultured fibroblasts. MMA exacerbated bleomycin-induced mouse lung fibrosis and induced a profibrotic phenotype in both epithelial cells and fibroblasts through activation of the canonical transforming growth factor-ß/Smad pathway. Overall, our findings unveil an alteration of propionate metabolism in IPF, leading to MMA accumulation, thus exacerbating lung fibrosis through promoting profibrotic phenotypic transitions via the canonical transforming growth factor-ß/Smad signaling pathway.

10.
Blood ; 142(10): 903-917, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37319434

RESUMEN

The bone marrow microenvironment (BMM) can regulate leukemia stem cells (LSCs) via secreted factors. Increasing evidence suggests that dissecting the mechanisms by which the BMM maintains LSCs may lead to the development of effective therapies for the eradication of leukemia. Inhibitor of DNA binding 1 (ID1), a key transcriptional regulator in LSCs, previously identified by us, controls cytokine production in the BMM, but the role of ID1 in acute myeloid leukemia (AML) BMM remains obscure. Here, we report that ID1 is highly expressed in the BMM of patients with AML, especially in BM mesenchymal stem cells, and that the high expression of ID1 in the AML BMM is induced by BMP6, secreted from AML cells. Knocking out ID1 in mesenchymal cells significantly suppresses the proliferation of cocultured AML cells. Loss of Id1 in the BMM results in impaired AML progression in AML mouse models. Mechanistically, we found that Id1 deficiency significantly reduces SP1 protein levels in mesenchymal cells cocultured with AML cells. Using ID1-interactome analysis, we found that ID1 interacts with RNF4, an E3 ubiquitin ligase, and causes a decrease in SP1 ubiquitination. Disrupting the ID1-RNF4 interaction via truncation in mesenchymal cells significantly reduces SP1 protein levels and delays AML cell proliferation. We identify that the target of Sp1, Angptl7, is the primary differentially expression protein factor in Id1-deficient BM supernatant fluid to regulate AML progression in mice. Our study highlights the critical role of ID1 in the AML BMM and aids the development of therapeutic strategies for AML.


Asunto(s)
Proteína 7 Similar a la Angiopoyetina , Proteína 1 Inhibidora de la Diferenciación , Leucemia Mieloide Aguda , Animales , Ratones , Proteína 7 Similar a la Angiopoyetina/genética , Proteína 7 Similar a la Angiopoyetina/metabolismo , Médula Ósea/metabolismo , Modelos Animales de Enfermedad , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Microambiente Tumoral , Humanos , Proteína 1 Inhibidora de la Diferenciación/metabolismo
11.
FASEB J ; 38(8): e23612, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38648494

RESUMEN

Considerable progress has been made in understanding the function of alveolar epithelial cells in a quiescent state and regeneration mechanism after lung injury. Lung injury occurs commonly from severe viral and bacterial infections, inhalation lung injury, and indirect injury sepsis. A series of pathological mechanisms caused by excessive injury, such as apoptosis, autophagy, senescence, and ferroptosis, have been studied. Recovery from lung injury requires the integrity of the alveolar epithelial cell barrier and the realization of gas exchange function. Regeneration mechanisms include the participation of epithelial progenitor cells and various niche cells involving several signaling pathways and proteins. While alveoli are damaged, alveolar type II (AT2) cells proliferate and differentiate into alveolar type I (AT1) cells to repair the damaged alveolar epithelial layer. Alveolar epithelial cells are surrounded by various cells, such as fibroblasts, endothelial cells, and various immune cells, which affect the proliferation and differentiation of AT2 cells through paracrine during alveolar regeneration. Besides, airway epithelial cells also contribute to the repair and regeneration process of alveolar epithelium. In this review, we mainly discuss the participation of epithelial progenitor cells and various niche cells involving several signaling pathways and transcription factors.


Asunto(s)
Células Epiteliales Alveolares , Lesión Pulmonar , Regeneración , Humanos , Regeneración/fisiología , Animales , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/patología , Células Madre/metabolismo , Células Madre/fisiología , Alveolos Pulmonares/patología , Alveolos Pulmonares/metabolismo , Transducción de Señal , Diferenciación Celular
12.
Mol Cell ; 67(2): 308-321.e6, 2017 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-28732206

RESUMEN

Enhancer activation is a critical step for gene activation. Here we report an epigenetic crosstalk at enhancers between the UTX (H3K27 demethylase)-MLL4 (H3K4 methyltransferase) complex and the histone acetyltransferase p300. We demonstrate that UTX, in a demethylase activity-independent manner, facilitates conversion of inactive enhancers in embryonic stem cells to an active (H3K4me1+/H3K27ac+) state by recruiting and coupling the enzymatic functions of MLL4 and p300. Loss of UTX leads to attenuated enhancer activity, characterized by reduced levels of H3K4me1 and H3K27ac as well as impaired transcription. The UTX-MLL4 complex enhances p300-dependent H3K27 acetylation through UTX-dependent stimulation of p300 recruitment, while MLL4-mediated H3K4 monomethylation, reciprocally, requires p300 function. Importantly, MLL4-generated H3K4me1 further enhances p300-dependent transcription. This work reveals a previously unrecognized cooperativity among enhancer-associated chromatin modulators, including a unique function for UTX, in establishing an "active enhancer landscape" and defines a detailed mechanism for the joint deposition of H3K4me1 and H3K27ac.


Asunto(s)
Cromatina/metabolismo , Proteína p300 Asociada a E1A/metabolismo , Células Madre Embrionarias/enzimología , Elementos de Facilitación Genéticos , Histona Demetilasas/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Transcripción Genética , Activación Transcripcional , Animales , Cromatina/genética , Ensamble y Desensamble de Cromatina , Proteína p300 Asociada a E1A/genética , Retroalimentación Fisiológica , Redes Reguladoras de Genes , Células HEK293 , Histona Demetilasas/genética , N-Metiltransferasa de Histona-Lisina/genética , Histonas/metabolismo , Humanos , Masculino , Metilación , Ratones , Interferencia de ARN , Transfección
13.
Mol Cell Proteomics ; 22(4): 100524, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36870568

RESUMEN

The heterogeneity of idiopathic pulmonary fibrosis (IPF) limits its diagnosis and treatment. The association between the pathophysiological features and the serum protein signatures of IPF currently remains unclear. The present study analyzed the specific proteins and patterns associated with the clinical parameters of IPF based on a serum proteomic dataset by data-independent acquisition using MS. Differentiated proteins in sera distinguished patients with IPF into three subgroups in signal pathways and overall survival. Aging-associated signatures by weighted gene correlation network analysis coincidently provided clear and direct evidence that aging is a critical risk factor for IPF rather than a single biomarker. Expression of LDHA and CCT6A, which was associated with glucose metabolic reprogramming, was correlated with high serum lactic acid content in patients with IPF. Cross-model analysis and machine learning showed that a combinatorial biomarker accurately distinguished patients with IPF from healthy individuals with an area under the curve of 0.848 (95% CI = 0.684-0.941) and validated from another cohort and ELISA assay. This serum proteomic profile provides rigorous evidence that enables an understanding of the heterogeneity of IPF and protein alterations that could help in its diagnosis and treatment decisions.


Asunto(s)
Fibrosis Pulmonar Idiopática , Proteómica , Humanos , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/patología , Proteínas Sanguíneas , Biomarcadores , Chaperonina con TCP-1
14.
Genomics ; 116(4): 110860, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38776985

RESUMEN

Walnuts exhibit a higher resistance to diseases, though they are not completely immune. This study focuses on the Pectin methylesterase (PME) gene family to investigate whether it is involved in disease resistance in walnuts. These 21 genes are distributed across 12 chromosomes, with four pairs demonstrating homology. Variations in conserved motifs and gene structures suggest diverse functions within the gene family. Phylogenetic and collinear gene pairs of the PME family indicate that the gene family has evolved in a relatively stable way. The cis-acting elements and gene ontology enrichment of these genes, underscores their potential role in bolstering walnuts' defense mechanisms. Transcriptomic analyses were conducted under conditions of Cryptosphaeria pullmanensis infestation and verified by RT-qPCR. The results showed that certain JrPME family genes were activated in response, leading to the hypothesis that some members may confer resistance to the disease.


Asunto(s)
Ascomicetos , Hidrolasas de Éster Carboxílico , Resistencia a la Enfermedad , Juglans , Familia de Multigenes , Enfermedades de las Plantas , Proteínas de Plantas , Juglans/microbiología , Juglans/genética , Ascomicetos/genética , Enfermedades de las Plantas/microbiología , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Regulación de la Expresión Génica de las Plantas
15.
Nano Lett ; 24(14): 4158-4164, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38557108

RESUMEN

As a quasi-layered ferrimagnetic material, Mn3Si2Te6 nanoflakes exhibit magnetoresistance behavior that is fundamentally different from their bulk crystal counterparts. They offer three key properties crucial for spintronics. First, at least 106 times faster response compared to that exhibited by bulk crystals has been observed in current-controlled resistance and magnetoresistance. Second, ultralow current density is required for resistance modulation (∼5 A/cm2). Third, electrically gate-tunable magnetoresistance has been realized. Theoretical calculations reveal that the unique magnetoresistance behavior in the Mn3Si2Te6 nanoflakes arises from a magnetic field induced band gap shift across the Fermi level. The rapid current induced resistance variation is attributed to spin-orbit torque, an intrinsically ultrafast process (∼nanoseconds). This study suggests promising avenues for spintronic applications. In addition, it highlights Mn3Si2Te6 nanoflakes as a suitable platform for investigating the intriguing physics underlying chiral orbital moments, magnetic field induced band variation, and spin torque.

16.
J Am Chem Soc ; 146(18): 12444-12453, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38680118

RESUMEN

Open Cu sites were loaded to the UiO-67 metal-organic framework (MOF) skeleton by introduction of flexible Cu-binding pyridylmethylamine (pyma) side chains to the biphenyldicarboxylate linkers. Distance between Cu centers in the MOF pores was tuned by controlling the density of metal-binding side chains. "Interacted" Cu-pair or "isolated" monomeric Cu sites were achieved with high and low (pyma)Cu side chain loading, respectively. Spectroscopic and theoretical studies indicate that "interacted" Cu pairs can effectively bind and activate molecular dioxygen to form Cu2O2 clusters, which showed high catalytic activity for aerobic oxidative C-N coupling. On the contrary, MOF catalyst bearing isolated monomeric Cu sites only showed modest catalytic activity. Enhancement in catalytic performance for the Cu-pair catalyst is attributed to the remote synergistic effect of the paired Cu site, which binds molecular dioxygen and cleaves the O═O bond in a collaborative manner. This work demonstrates that noncovalently interacted metal-pair sites can effectively activate inert small molecules and promote heterogeneous catalytic processes.

17.
Cancer Sci ; 115(7): 2235-2253, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38700108

RESUMEN

Triple-negative breast cancer (TNBC) has greater infiltration of M2-like macrophages (TAMs), which enhances cancer cell invasion and leads to a poor prognosis. TNBC progression is mediated by both tumor cells and the tumor microenvironment (TME). Here we elucidate the mechanism of the interaction between TNBC cells and TAMs. In this study, we confirmed that CD44v5 is highly expressed in TNBC, which drives TNBC cell metastasis and promotes TAM polarization by co-localizing with IL4Rα and inhibiting its internalization and degradation, thereby promoting activation of the STAT3/IL6 signaling axis. At the same time, TAMs also facilitate TNBC cell metastasis by secreting IL-4, IL-6, and other cytokines, in which the IL-4/IL-4R/STAT3/IL-6 signaling axis plays the same role for TNBC cells responding to TAMs. Moreover, we found that the above progress could be suppressed when the CD44v5 domain was blocked. We demonstrated that the CD44v5/IL-4R/STAT3/IL-6 signaling pathway plays a key role in TNBC cell metastasis, and in TNBC cells inducing TAM polarization and responding to TAMs, promoting metastasis. Collectively, we suggest that the CD44v5 domain may be a promising target for regulating the TME of TNBC as well as treating TNBC.


Asunto(s)
Receptores de Hialuranos , Factor de Transcripción STAT3 , Transducción de Señal , Neoplasias de la Mama Triple Negativas , Microambiente Tumoral , Macrófagos Asociados a Tumores , Humanos , Factor de Transcripción STAT3/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/genética , Receptores de Hialuranos/metabolismo , Femenino , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/inmunología , Línea Celular Tumoral , Animales , Ratones , Interleucina-6/metabolismo , Subunidad alfa del Receptor de Interleucina-4/metabolismo , Subunidad alfa del Receptor de Interleucina-4/genética , Interleucina-4/metabolismo
18.
J Gen Virol ; 105(1)2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38189334

RESUMEN

Phosphorylation and dephosphorylation of viral movement proteins plays a crucial role in regulating virus movement. Our study focused on investigating the movement protein TGBp1 of Bamboo mosaic virus (BaMV), which is a single-stranded positive-sense RNA virus. Specifically, we examined four potential phosphorylation sites (S15, S18, T58, and S247) within the TGBp1 protein. To study the impact of phosphorylation, we introduced amino acid substitutions at the selected sites. Alanine substitutions were used to prevent phosphorylation, while aspartate substitutions were employed to mimic phosphorylation. Our findings suggest that mimicking phosphorylation at S15, S18 and T58 of TGBp1 might be linked to silencing suppressor activities. The phosphorylated form at these sites exhibits a loss of silencing suppressor activity, leading to reduced viral accumulation in the inoculated leaves. Furthermore, mimicking phosphorylation at residues S15 and S18 could diminish viral accumulation at the single-cell level, while doing so at residue T58 could influence virus movement. However, mimicking phosphorylation at residue S247 does not appear to be relevant to both functions of TGBp1. Overall, our study provides insights into the functional significance of specific phosphorylation sites in BaMV TGBp1, illuminating the regulatory mechanisms involved in virus movement and silencing suppression.


Asunto(s)
Potexvirus , Fosforilación , Potexvirus/genética , Alanina , Sustitución de Aminoácidos
19.
J Gen Virol ; 105(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38809251

RESUMEN

Tick-borne orthoflaviviruses (TBFs) are classified into three conventional groups based on genetics and ecology: mammalian, seabird and probable-TBF group. Recently, a fourth basal group has been identified in Rhipicephalus ticks from Africa: Mpulungu flavivirus (MPFV) in Zambia and Ngoye virus (NGOV) in Senegal. Despite attempts, isolating these viruses in vertebrate and invertebrate cell lines or intracerebral injection of newborn mice with virus-containing homogenates has remained unsuccessful. In this study, we report the discovery of Xinyang flavivirus (XiFV) in Haemaphysalis flava ticks from Xìnyáng, Henan Province, China. Phylogenetic analysis shows that XiFV was most closely related to MPFV and NGOV, marking the first identification of this tick orthoflavivirus group in Asia. We developed a reverse transcriptase quantitative PCR assay to screen wild-collected ticks and egg clutches, with absolute infection rates of 20.75 % in adult females and 15.19 % in egg clutches, suggesting that XiFV could be potentially spread through transovarial transmission. To examine potential host range, dinucleotide composition analyses revealed that XiFV, MPFV and NGOV share a closer composition to classical insect-specific orthoflaviviruses than to vertebrate-infecting TBFs, suggesting that XiFV could be a tick-only orthoflavivirus. Additionally, both XiFV and MPFV lack a furin cleavage site in the prM protein, unlike other TBFs, suggesting these viruses might exist towards a biased immature particle state. To examine this, chimeric Binjari virus with XIFV-prME (bXiFV) was generated, purified and analysed by SDS-PAGE and negative-stain transmission electron microscopy, suggesting prototypical orthoflavivirus size (~50 nm) and bias towards uncleaved prM. In silico structural analyses of the 3'-untranslated regions show that XiFV forms up to five pseudo-knot-containing stem-loops and a prototypical orthoflavivirus dumbbell element, suggesting the potential for multiple exoribonuclease-resistant RNA structures.


Asunto(s)
Flavivirus , Ixodidae , Filogenia , Animales , Flavivirus/genética , Flavivirus/clasificación , Flavivirus/aislamiento & purificación , China , Ixodidae/virología , Femenino
20.
Planta ; 260(1): 26, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861179

RESUMEN

MAIN CONCLUSION: CaTPS2 and CaTPS3 were significantly expressed in flowers of Curcuma alismatifolia 'Shadow' and demonstrated bifunctional enzyme activity, CaTPS2 generated linalool and nerolidol as products, and CaTPS3 catalyzed ß-myrcene and ß-farnesene formation. This study presents the discovery and functional characterization of floral terpene synthase (TPS) genes in Curcuma alismatifolia 'Shadow', a cultivar renowned for its unique fragrance. Addressing the gap in understanding the genetic basis of floral scent in this species, we identified eight TPS genes through comprehensive transcriptome sequencing. Among these, CaTPS2 and CaTPS3 were significantly expressed in floral tissues and demonstrated bifunctional enzyme activity corresponding to the major volatile compounds detected in 'Shadow'. Functional analyses, including in vitro assays complemented with rigorous controls and alternative identification methods, elucidated the roles of these TPS genes in terpenoid biosynthesis. In vitro studies were conducted via heterologous expression in E. coli, followed by purification of the recombinant protein using affinity chromatography, enzyme assays were performed with GPP/FPP as the substrate, and volatile products were inserted into the GC-MS for analysis. Partially purified recombinant protein of CaTPS2 catalyzed GPP and FPP to produce linalool and nerolidol, respectively, while partially purified recombinant protein of CaTPS3 generated ß-myrcene and ß-farnesene with GPP and FPP as substrates, respectively. Real-time quantitative PCR further validated the expression patterns of these genes, correlating with terpenoid accumulation in different plant tissues. Our findings illuminate the molecular mechanisms underpinning floral fragrance in C. alismatifolia and provide a foundation for future genetic enhancements of floral scent in ornamental plants. This study, therefore, contributes to the broader understanding of terpenoid biosynthesis in plant fragrances, paving the way for biotechnological applications in horticulture plant breeding.


Asunto(s)
Monoterpenos Acíclicos , Transferasas Alquil y Aril , Curcuma , Flores , Sesquiterpenos , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Flores/genética , Flores/enzimología , Flores/metabolismo , Sesquiterpenos/metabolismo , Monoterpenos Acíclicos/metabolismo , Curcuma/genética , Curcuma/enzimología , Curcuma/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Terpenos/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Filogenia , Odorantes
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