RESUMEN
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.
Asunto(s)
Proteínas Portadoras , Linfoma de Células B , Esteroles , Animales , Humanos , Ratones , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Esteroles/metabolismo , Linfoma de Células B/metabolismoRESUMEN
Human health is dependent upon environmental exposures, yet the diversity and variation in exposures are poorly understood. We developed a sensitive method to monitor personal airborne biological and chemical exposures and followed the personal exposomes of 15 individuals for up to 890 days and over 66 distinct geographical locations. We found that individuals are potentially exposed to thousands of pan-domain species and chemical compounds, including insecticides and carcinogens. Personal biological and chemical exposomes are highly dynamic and vary spatiotemporally, even for individuals located in the same general geographical region. Integrated analysis of biological and chemical exposomes revealed strong location-dependent relationships. Finally, construction of an exposome interaction network demonstrated the presence of distinct yet interconnected human- and environment-centric clouds, comprised of interacting ecosystems such as human, flora, pets, and arthropods. Overall, we demonstrate that human exposomes are diverse, dynamic, spatiotemporally-driven interaction networks with the potential to impact human health.
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Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Adulto , Animales , Ecosistema , Enfermedades Ambientales/etiología , HumanosRESUMEN
Adoptive T cell therapies have produced exceptional responses in a subset of patients with cancer. However, therapeutic efficacy can be hindered by poor T cell persistence and function1. In human T cell cancers, evolution of the disease positively selects for mutations that improve fitness of T cells in challenging situations analogous to those faced by therapeutic T cells. Therefore, we reasoned that these mutations could be co-opted to improve T cell therapies. Here we systematically screened the effects of 71 mutations from T cell neoplasms on T cell signalling, cytokine production and in vivo persistence in tumours. We identify a gene fusion, CARD11-PIK3R3, found in a CD4+ cutaneous T cell lymphoma2, that augments CARD11-BCL10-MALT1 complex signalling and anti-tumour efficacy of therapeutic T cells in several immunotherapy-refractory models in an antigen-dependent manner. Underscoring its potential to be deployed safely, CARD11-PIK3R3-expressing cells were followed up to 418 days after T cell transfer in vivo without evidence of malignant transformation. Collectively, our results indicate that exploiting naturally occurring mutations represents a promising approach to explore the extremes of T cell biology and discover how solutions derived from evolution of malignant T cells can improve a broad range of T cell therapies.
Asunto(s)
Evolución Molecular , Inmunoterapia Adoptiva , Linfoma Cutáneo de Células T , Mutación , Linfocitos T , Humanos , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Citocinas/biosíntesis , Citocinas/inmunología , Citocinas/metabolismo , Guanilato Ciclasa/genética , Guanilato Ciclasa/metabolismo , Inmunoterapia Adoptiva/métodos , Linfoma Cutáneo de Células T/genética , Linfoma Cutáneo de Células T/inmunología , Linfoma Cutáneo de Células T/patología , Linfoma Cutáneo de Células T/terapia , Fosfatidilinositol 3-Quinasas , Transducción de Señal/genética , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linfocitos T/trasplanteRESUMEN
Increasing grain yield is a major goal of breeders due to the rising global demand for food. We previously reported that the miR397-LACCASE (OsLAC) module regulates brassinosteroid (BR) signaling and grain yield in rice (Oryza sativa). However, the precise roles of laccase enzymes in the BR pathway remain unclear. Here, we report that OsLAC controls grain yield by preventing the turnover of TRANSTHYRETIN-LIKE (OsTTL), a negative regulator of BR signaling. Overexpressing OsTTL decreased BR sensitivity in rice, while loss-of-function of OsTTL led to enhanced BR signaling and increased grain yield. OsLAC directly binds to OsTTL and regulates its phosphorylation-mediated turnover. The phosphorylation site Ser226 of OsTTL is essential for its ubiquitination and degradation. Overexpressing the dephosphorylation-mimic form of OsTTL (OsTTLS226A) resulted in more severe defects than did overexpressing OsTTL. These findings provide insight into the role of an ancient laccase in BR signaling and suggest that the OsLAC-OsTTL module could serve as a target for improving grain yield.
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Regulación de la Expresión Génica de las Plantas , Lacasa , MicroARNs , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Oryza/enzimología , Lacasa/metabolismo , Lacasa/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , MicroARNs/genética , MicroARNs/metabolismo , Fosforilación , Grano Comestible/crecimiento & desarrollo , Grano Comestible/genética , Grano Comestible/metabolismo , Transducción de Señal , Plantas Modificadas Genéticamente , Brasinoesteroides/metabolismoRESUMEN
Drought, which can induce osmotic stress, is the leading environmental constraint on crop productivity. Plants in both agricultural and natural settings have developed various mechanisms to cope with drought stress. The identification of genes associated with drought stress tolerance and understanding the underlying regulatory mechanisms are prerequisites for developing molecular manipulation strategies to address this issue. Here, we reported that the G-BOX FACTOR 14-3-3f (14-3-3 protein OsGF14f) positively modulates osmotic stress tolerance in rice (Oryza sativa). OsGF14f transgenic lines had no obvious change in crucial agronomic traits including yield and plant height. OsGF14f is transcriptionally induced by PEG treatment, and in rice, overexpression or knockout of this gene leads to enhanced or weakened osmotic stress tolerance, respectively. Furthermore, OsGF14f positively regulates abscisic acid (ABA) responses by interacting with the core ABA-responsive transcription factor BASIC LEUCINE ZIPPER 23 (OsbZIP23) to enhance its transcriptional regulation activity toward downstream target genes. Further genetic analysis showed that OsGF14f is required for the full function of OsbZIP23 in rice osmotic response, and OsGF14f-mediated osmotic stress tolerance partially depends on OsbZIP23. Interestingly, OsGF14f is a direct target gene of OsbZIP23. Taken together, our findings reveal a genetic and molecular framework by which the OsGF14f-OsbZIP23 complex modulates rice osmotic response, providing targets for developing drought-tolerant crops.
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Oryza , Oryza/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Estrés Fisiológico/genética , Presión Osmótica , Proteínas de Plantas/metabolismo , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismoRESUMEN
Increasing planting density has been adopted as an effective means to increase maize (Zea mays) yield. Competition for light from neighbors can trigger plant shade avoidance syndrome, which includes accelerated flowering. However, the regulatory networks of maize inflorescence development in response to high-density planting remain poorly understood. In this study, we showed that shade-mimicking treatments cause precocious development of the tassels and ears. Comparative transcriptome profiling analyses revealed the enrichment of phytohormone-related genes and transcriptional regulators among the genes co-regulated by developmental progression and simulated shade. Network analysis showed that three homologous Squamosa promoter binding protein (SBP)-like (SPL) transcription factors, Unbranched2 (UB2), Unbranched3 (UB3), and Tasselsheath4 (TSH4), individually exhibited connectivity to over 2,400 genes across the V3-to-V9 stages of tassel development. In addition, we showed that the ub2 ub3 double mutant and tsh4 single mutant were almost insensitive to simulated shade treatments. Moreover, we demonstrated that UB2/UB3/TSH4 could directly regulate the expression of Barren inflorescence2 (BIF2) and Zea mays teosinte branched1/cycloidea/proliferating cell factor30 (ZmTCP30). Furthermore, we functionally verified a role of ZmTCP30 in regulating tassel branching and ear development. Our results reveal a UB2/UB3/TSH4-anchored transcriptional regulatory network of maize inflorescence development and provide valuable targets for breeding shade-tolerant maize cultivars.
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Inflorescencia , Zea mays , Inflorescencia/genética , Inflorescencia/metabolismo , Zea mays/metabolismo , Redes Reguladoras de Genes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Maize (Zea mays) originated in southern Mexico and has spread over a wide latitudinal range. Maize expansion from tropical to temperate regions has necessitated a reduction of its photoperiod sensitivity. In this study, we cloned a quantitative trait locus (QTL) regulating flowering time in maize and show that the maize ortholog of Arabidopsis thaliana EARLY FLOWERING3, ZmELF3.1, is the causal locus. We demonstrate that ZmELF3.1 and ZmELF3.2 proteins can physically interact with ZmELF4.1/4.2 and ZmLUX1/2, to form evening complex(es; ECs) in the maize circadian clock. Loss-of-function mutants for ZmELF3.1/3.2 and ZmLUX1/2 exhibited delayed flowering under long-day and short-day conditions. We show that EC directly represses the expression of several flowering suppressor genes, such as the CONSTANS, CONSTANS-LIKE, TOC1 (CCT) genes ZmCCT9 and ZmCCT10, ZmCONSTANS-LIKE 3, and the PSEUDORESPONSE REGULATOR (PRR) genes ZmPRR37a and ZmPRR73, thus alleviating their inhibition, allowing florigen gene expression and promoting flowering. Further, we identify two closely linked retrotransposons located in the ZmELF3.1 promoter that regulate the expression levels of ZmELF3.1 and may have been positively selected during postdomestication spread of maize from tropical to temperate regions during the pre-Columbian era. These findings provide insights into circadian clock-mediated regulation of photoperiodic flowering in maize and new targets of genetic improvement for breeding.
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Arabidopsis , Zea mays , Zea mays/metabolismo , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptación Fisiológica/genética , Aclimatación/genética , Fotoperiodo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/genéticaRESUMEN
Physical interactions between distal regulatory elements have a key role in regulating gene expression, but the extent to which these interactions vary between cell types and contribute to cell-type-specific gene expression remains unclear. Here, to address these questions as part of phase III of the Encyclopedia of DNA Elements (ENCODE), we mapped cohesin-mediated chromatin loops, using chromatin interaction analysis by paired-end tag sequencing (ChIA-PET), and analysed gene expression in 24 diverse human cell types, including core ENCODE cell lines. Twenty-eight per cent of all chromatin loops vary across cell types; these variations modestly correlate with changes in gene expression and are effective at grouping cell types according to their tissue of origin. The connectivity of genes corresponds to different functional classes, with housekeeping genes having few contacts, and dosage-sensitive genes being more connected to enhancer elements. This atlas of chromatin loops complements the diverse maps of regulatory architecture that comprise the ENCODE Encyclopedia, and will help to support emerging analyses of genome structure and function.
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Proteínas de Ciclo Celular/metabolismo , Cromatina/química , Cromatina/genética , Proteínas Cromosómicas no Histona/metabolismo , Genoma Humano/genética , Anotación de Secuencia Molecular , Empalme Alternativo/genética , Diferenciación Celular/genética , Línea Celular , Células/metabolismo , Cromatina/metabolismo , Secuenciación de Inmunoprecipitación de Cromatina , Elementos de Facilitación Genéticos/genética , Regulación de la Expresión Génica , Humanos , Conformación Molecular , Regiones Promotoras Genéticas/genética , CohesinasRESUMEN
Lysyl oxidase-like 2 (LOXL2) is a member of the lysyl oxidase family and has the ability to catalyze the cross-linking of extracellular matrix collagen and elastin. High expression of LOXL2 is related to tumor cell proliferation, invasion, and metastasis. LOXL2 contains 14 exons. Previous studies have found that LOXL2 has abnormal alternative splicing and exon skipping in a variety of tissues and cells, resulting in a new alternatively spliced isoform denoted LOXL2Δ13. LOXL2Δ13 lacks LOXL2WT exon 13, but its encoded protein has greater ability to induce tumor cell proliferation, invasion, and metastasis. However, the molecular events that produce LOXL2Δ13 are still unclear. In this study, we found that overexpression of the splicing factor hnRNPA1 in cells can regulate the alternative splicing of LOXL2 and increase the expression of LOXL2Δ13. The exonic splicing silencer exists at the 3' splice site and 5' splice site of LOXL2 exon 13. HnRNPA1 can bind to the exonic splicing silencer and inhibit the inclusion of exon 13. The RRM domain of hnRNPA1 and phosphorylation of hnRNPA1 at S91 and S95 are important for the regulation of LOXL2 alternative splicing. These results show that hnRNPA1 is a splicing factor that enhances the production of LOXL2Δ13.
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Empalme Alternativo , Aminoácido Oxidorreductasas , Exones , Ribonucleoproteína Nuclear Heterogénea A1 , Ribonucleoproteína Nuclear Heterogénea A1/metabolismo , Ribonucleoproteína Nuclear Heterogénea A1/genética , Humanos , Aminoácido Oxidorreductasas/genética , Aminoácido Oxidorreductasas/metabolismo , Células HEK293 , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismoRESUMEN
Long-term visualization of the dynamic interactions between intracellular structures throughout the three-dimensional space of whole live cells is essential to better understand their functions, but this task remains challenging due to the limitations of existing three-dimensional fluorescence microscopy techniques, such as an insufficient axial resolution, low volumetric imaging rate and photobleaching. Here, we present the combination of a progressive deep-learning super-resolution strategy with a double-ring-modulated selective plane illumination microscopy design capable of visualizing the dynamics of intracellular structures in live cells for hours at an isotropic spatial resolution of roughly 100 nm in three dimensions at speeds up to roughly 17 Hz. Using this approach, we reveal the complex spatial relationships and interactions between endoplasmic reticulum (ER) and mitochondria throughout live cells, providing new insights into ER-mediated mitochondrial division. We also examined the motion of Drp1 oligomers involved in mitochondrial fission and revealed the dynamic interactions between Drp1 and mitochondria in three dimensions.
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Retículo Endoplásmico , Mitocondrias , Retículo Endoplásmico/metabolismo , Imagenología Tridimensional/métodos , Microscopía Fluorescente/métodos , FotoblanqueoRESUMEN
Several starch synthesis regulators have been identified, but these regulators are situated in the terminus of the regulatory network. Their upstream regulators and the complex regulatory network formed between these regulators remain largely unknown. A previous study demonstrated that NAM, ATAF, and CUC (NAC) transcription factors, OsNAC20 and OsNAC26 (OsNAC20/26), redundantly and positively regulate the accumulation of storage material in rice (Oryza sativa) endosperm. In this study, we detected OsNAC25 as an upstream regulator and interacting protein of OsNAC20/26. Both OsNAC25 mutation and OE resulted in a chalky seed phenotype, decreased starch content, and reduced expression of starch synthesis-related genes, but the mechanisms were different. In the osnac25 mutant, decreased expression of OsNAC20/26 resulted in reduced starch synthesis; however, in OsNAC25-overexpressing plants, the OsNAC25-OsNAC20/26 complex inhibited OsNAC20/26 binding to the promoter of starch synthesis-related genes. In addition, OsNAC20/26 positively regulated OsNAC25. Therefore, the mutual regulation between OsNAC25 and OsNAC20/26 forms a positive regulatory loop to stimulate the expression of starch synthesis-related genes and meet the great demand for starch accumulation in the grain filling stage. Simultaneously, a negative regulatory loop forms among the 3 proteins to avoid the excessive expression of starch synthesis-related genes. Collectively, our findings demonstrate that both promotion and inhibition mechanisms between OsNAC25 and OsNAC20/26 are essential for maintaining stable expression of starch synthesis-related genes and normal starch accumulation.
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Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Almidón , Factores de Transcripción , Oryza/genética , Oryza/metabolismo , Almidón/metabolismo , Almidón/biosíntesis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Endospermo/metabolismo , Endospermo/genéticaRESUMEN
Root development influences plant responses to environmental conditions, and well-developed rooting enhances plant survival under abiotic stress. However, the molecular and genetic mechanisms underlying root development and abiotic stress tolerance in plants remain unclear. In this study, we identified the MYB transcription factor-encoding gene IbMYB73 by cDNA-amplified fragment length polymorphism and RNA-seq analyses. IbMYB73 expression was greatly suppressed under abiotic stress in the roots of the salt-tolerant sweet potato (Ipomoea batatas) line ND98, and its promoter activity in roots was significantly reduced by abscisic acid (ABA), NaCl, and mannitol treatments. Overexpression of IbMYB73 significantly inhibited adventitious root growth and abiotic stress tolerance, whereas IbMYB73-RNAi plants displayed the opposite pattern. IbMYB73 influenced the transcription of genes involved in the ABA pathway. Furthermore, IbMYB73 formed homodimers and activated the transcription of ABA-responsive protein IbGER5 by binding to an MYB binding sites I motif in its promoter. IbGER5 overexpression significantly inhibited adventitious root growth and abiotic stress tolerance concomitantly with a reduction in ABA content, while IbGER5-RNAi plants showed the opposite effect. Collectively, our results demonstrated that the IbMYB73-IbGER5 module regulates ABA-dependent adventitious root growth and abiotic stress tolerance in sweet potato, which provides candidate genes for the development of elite crop varieties with well-developed root-mediated abiotic stress tolerance.
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Ácido Abscísico , Ipomoea batatas , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Estrés Fisiológico/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
The precise timing of flowering plays a pivotal role in ensuring successful plant reproduction and seed production. This process is intricately governed by complex genetic networks that integrate internal and external signals. This study delved into the regulatory function of microRNA397 (miR397) and its target gene LACCASE-15 (OsLAC15) in modulating flowering traits in rice (Oryza sativa). Overexpression of miR397 led to earlier heading dates, decreased number of leaves on the main stem, and accelerated differentiation of the spikelet meristem. Conversely, overexpression of OsLAC15 resulted in delayed flowering and prolonged vegetative growth. Through biochemical and physiological assays, we uncovered that miR397-OsLAC15 had a profound impact on carbohydrate accumulation and photosynthetic assimilation, consequently enhancing the photosynthetic intensity in miR397-overexpressing rice plants. Notably, we identified that OsLAC15 is at least partially localized within the peroxisome organelle, where it regulates the photorespiration pathway. Moreover, we observed that a high CO2 concentration could rescue the late flowering phenotype in OsLAC15-overexpressing plants. These findings shed valuable insights into the regulatory mechanisms of miR397-OsLAC15 in rice flowering and provided potential strategies for developing crop varieties with early flowering and high-yield traits through genetic breeding.
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Oryza , Oryza/metabolismo , Flores/fisiología , Fitomejoramiento , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Reproducción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
Brain metastases account for more than 50 % of intracranial central nervous system tumors. The blood-brain barrier (BBB) is mainly composed of endothelial cells, which exhibit low endocytosis and high efflux pumps. Although they are connected by continuous tight junctions and serve as a protective insulation, the BBB does not prevent the development of brain metastases from non-small cell lung cancer (NSCLC). Improving understanding on the mechanisms underlying the development of brain metastasis and the differential molecular characteristics relative to the primary tumor are therefore key in the treatment of brain metastases. This study evaluated the differential expression of miR-522-3p in NSCLC and brain metastases using the Gene Expression Omnibus database. NSCLC brain metastasis model was constructed to screen for cell lines that demonstrated high potential for brain metastasis; We also observed differential expression of miRNA-522-3p in the paraffin-embedded specimens of non-small cell lung cancer and brain metastases from our hospital. The molecular biological functions of miRNA-522-3p were verified using 5-ethynyl-2'-deoxyuridine (EdU) proliferation assay and Transwell invasion assays. RNA-seq was employed to identify downstream target proteins, and the dual-luciferase reporter assay confirmed Tensin 1 (TNS1), a protein that links the actin cytoskeleton to the extracellular matrix, as the downstream regulatory target protein. In vitro blood-brain barrier models and co-culture models were constructed to further identify the role of miRNA-522-3p and TNS1; the expression of BBB-related proteins (ZO-1 and OLCN) was also identified. In vivo experiments were performed to verify the effects of miRNA-522-3p on the time and incidence of NSCLC brain metastasis. The results showed significantly high expression in GSE51666; consistent results were obtained in brain metastasis cells and paraffin samples. RNA-seq combined with miRNA target protein prediction demonstrated TNS1 to be directly downstream of miR-522-3p and to be associated with cell proliferation and invasion. By regulating ZO-1 and OCLN expression, mi-522-3p/TNS1 may increase tumor cell penetration through the BBB while decreasing its permeability. In vivo, miR-522-3p was further demonstrated to significantly promote the formation of brain metastases. miR-522-3p/TNS1 can affect BBB permeability and encourage the growth of brain metastases by modifying the BBB TJ proteins. This axis offers new therapeutic targets for the prevention of brain metastasis.
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Barrera Hematoencefálica , Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , MicroARNs , Tensinas , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/metabolismo , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Animales , Regulación Neoplásica de la Expresión Génica/genética , Ratones , Tensinas/metabolismo , Tensinas/genética , Proliferación Celular/genética , Ratones Desnudos , Línea Celular Tumoral , Permeabilidad , Ratones Endogámicos BALB C , Movimiento Celular/genéticaRESUMEN
Glucagon-like peptide-1 receptor (GLP-1R) agonists are effective in treating type 2 diabetes and obesity with proven cardiovascular benefits. However, most of these agonists are peptides and require subcutaneous injection except for orally available semaglutide. Boc5 was identified as the first orthosteric nonpeptidic agonist of GLP-1R that mimics a broad spectrum of bioactivities of GLP-1 in vitro and in vivo. Here, we report the cryoelectron microscopy structures of Boc5 and its analog WB4-24 in complex with the human GLP-1R and Gs protein. Bound to the extracellular domain, extracellular loop 2, and transmembrane (TM) helices 1, 2, 3, and 7, one arm of both compounds was inserted deeply into the bottom of the orthosteric binding pocket that is usually accessible by peptidic agonists, thereby partially overlapping with the residues A8 to D15 in GLP-1. The other three arms, meanwhile, extended to the TM1-TM7, TM1-TM2, and TM2-TM3 clefts, showing an interaction feature substantially similar to the previously known small-molecule agonist LY3502970. Such a unique binding mode creates a distinct conformation that confers both peptidomimetic agonism and biased signaling induced by nonpeptidic modulators at GLP-1R. Further, the conformational difference between Boc5 and WB4-24, two closed related compounds, provides a structural framework for fine-tuning of pharmacological efficacy in the development of future small-molecule therapeutics targeting GLP-1R.
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Ciclobutanos , Receptor del Péptido 1 Similar al Glucagón , Peptidomiméticos , Microscopía por Crioelectrón , Ciclobutanos/química , Ciclobutanos/farmacología , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/química , Humanos , Peptidomiméticos/química , Peptidomiméticos/farmacología , Dominios ProteicosRESUMEN
BACKGROUND: MUPPITS-2 was a randomized, placebo-controlled clinical trial that demonstrated mepolizumab (anti-IL-5) reduced exacerbations and blood and airway eosinophils in urban children with severe eosinophilic asthma. Despite this reduction in eosinophilia, exacerbation risk persisted in certain patients treated with mepolizumab. This raises the possibility that subpopulations of airway eosinophils exist that contribute to breakthrough exacerbations. OBJECTIVE: We aimed to determine the effect of mepolizumab on airway eosinophils in childhood asthma. METHODS: Sputum samples were obtained from 53 MUPPITS-2 participants. Airway eosinophils were characterized using mass cytometry and grouped into subpopulations using unsupervised clustering analyses of 38 surface and intracellular markers. Differences in frequency and immunophenotype of sputum eosinophil subpopulations were assessed based on treatment arm and frequency of exacerbations. RESULTS: Median sputum eosinophils were significantly lower among participants treated with mepolizumab compared with placebo (58% lower, 0.35% difference [95% CI 0.01, 0.74], P = .04). Clustering analysis identified 3 subpopulations of sputum eosinophils with varied expression of CD62L. CD62Lint and CD62Lhi eosinophils exhibited significantly elevated activation marker and eosinophil peroxidase expression, respectively. In mepolizumab-treated participants, CD62Lint and CD62Lhi eosinophils were more abundant in participants who experienced exacerbations than in those who did not (100% higher for CD62Lint, 0.04% difference [95% CI 0.0, 0.13], P = .04; 93% higher for CD62Lhi, 0.21% difference [95% CI 0.0, 0.77], P = .04). CONCLUSIONS: Children with eosinophilic asthma treated with mepolizumab had significantly lower sputum eosinophils. However, CD62Lint and CD62Lhi eosinophils were significantly elevated in children on mepolizumab who had exacerbations, suggesting that eosinophil subpopulations exist that contribute to exacerbations despite anti-IL-5 treatment.
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Antiasmáticos , Anticuerpos Monoclonales Humanizados , Asma , Eosinófilos , Esputo , Humanos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Eosinófilos/inmunología , Niño , Esputo/citología , Esputo/inmunología , Masculino , Femenino , Asma/tratamiento farmacológico , Asma/inmunología , Antiasmáticos/uso terapéutico , Adolescente , Interleucina-5 , Progresión de la EnfermedadRESUMEN
The unique "Iron Addiction" feature of cancer stem cells (CSCs) with tumorigenicity and plasticity generally contributes to the tumor recurrence and metastasis after a lumpectomy. Herein, a novel "Ferroptosis Amplification" strategy is developed based on integrating gallic acid-modified FeOOH (GFP) and gallocyanine into Pluronic F-127 (F127) and carboxylated chitosan (CC)-based hydrogel for CSCs eradication. This "Ferroptosis Amplifier" hydrogel is thermally sensitive and achieves rapid gelation at the postsurgical wound in a breast tumor model. Specifically, gallocyanine, as the Dickkopf-1 (DKK1) inhibitor, can decrease the expression of SLC7A11 and GPX4 and synergistically induce ferroptosis of CSCs with GFP. Encouragingly, it is found that this combination suppresses the migratory and invasive capability of cancer cells via the downregulation of matrix metalloproteinase 7 (MMP7). The in vivo results further confirm that this "Ferroptosis Amplification" strategy is efficient in preventing tumor relapse and lung metastasis, manifesting an effective and promising postsurgical treatment for breast cancer.
Asunto(s)
Neoplasias de la Mama , Ferroptosis , Hidrogeles , Células Madre Neoplásicas , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Hidrogeles/química , Humanos , Animales , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Femenino , Ratones , Ferroptosis/efectos de los fármacos , Línea Celular Tumoral , Poloxámero/química , Poloxámero/farmacología , Quitosano/química , Quitosano/farmacología , Quitosano/análogos & derivados , Ácido Gálico/farmacología , Ácido Gálico/química , Ácido Gálico/uso terapéuticoRESUMEN
Bimetallic nanowires play important roles in the fields of electronics and mechanics. However, their structure types and morphological control methods are limited, especially for systems with low lattice mismatch. Herein, for a Cu-Ni bimetallic system with lattice mismatch ratio less than 2.5%, a novel preparation approach of various Cu-Ni nanowires dominated by Ni(II) reduction kinetics is presented. With the increase of Ni(II) reduction rate, the core-shell Cu@Ni straight nanowires, the asymmetric Cu-Ni nanocurves, and asymmetric Cu-Ni nanocoils can be prepared, respectively. The formation of Cu-Ni nanowires with different structures can be divided into the growth of Cu nanowires and the deposition of Ni. The regulatory effects were revealed by establishing a kinetic model for Ni(II) reduction. For the novel Cu-Ni asymmetrically distributed nanocurves and nanocoils, the formation mechanism was proposed by considering the Cu nanowire bending due to the rearrangement of surface ligand and bending-induced symmetry breaking of Ni(II) reduction.
RESUMEN
Solar-driven photothermal catalytic H2 production from lignocellulosic biomass was achieved by using 1T-2H MoS2 with tunable Lewis acidic sites as catalysts in an alkaline aqueous solution, in which the number of Lewis acidic sites derived from the exposed Mo edges of MoS2 was successfully regulated by both the formation of an edge-terminated 1T-2H phase structure and tunable layer number. Owing to the abundant Lewis acidic sites for the oxygenolysis of lignocellulosic biomass, the 1T-2H MoS2 catalyst shows high photothermal catalytic lignocellulosic biomass-to-H2 transformation performance in polar wood chips, bamboo, rice straw corncobs, and rice hull aqueous solutions, and the highest H2 generation rate and solar-to-H2 (STH) efficiency respectively achieves 3661 µmol·h-1·g-1 and 0.18% in the polar wood chip system under 300 W Xe lamp illumination. This study provides a sustainable and cost-effective method for the direct transformation of renewable lignocellulosic biomass to H2 fuel driven by solar energy.
RESUMEN
BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illness (ARI) in older adults. Optimizing diagnosis could improve understanding of RSV burden. METHODS: We enrolled adults ≥50 years of age hospitalized with ARI and adults of any age hospitalized with congestive heart failure or chronic obstructive pulmonary disease exacerbations at two hospitals during two respiratory seasons (2018-2020). We collected nasopharyngeal (NP) and oropharyngeal (OP) swabs (n=1558), acute and convalescent sera (n=568), and expectorated sputum (n=153) from participants, and recorded standard-of-care (SOC) NP results (n=805). We measured RSV antibodies by two immunoassays and performed BioFire testing on respiratory specimens. RESULTS: Of 1,558 eligible participants, 92 (5.9%) tested positive for RSV by any diagnostic method. Combined NP/OP PCR yielded 58 positives, while separate NP and OP testing identified 11 additional positives (18.9% increase). Compared to Study NP/OP PCR alone, the addition of paired serology increased RSV detection by 42.9% (28 vs 40) among those with both specimen types, while the addition of SOC swab RT-PCR results increased RSV detection by 25.9% (47 vs 59). CONCLUSIONS: The addition of paired serology testing, SOC swab results, and separate testing of NP and OP swabs improved RSV diagnostic yield in hospitalized adults.