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1.
Nature ; 630(8018): 943-949, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38898271

RESUMEN

Spatial transcriptomics measures in situ gene expression at millions of locations within a tissue1, hitherto with some trade-off between transcriptome depth, spatial resolution and sample size2. Although integration of image-based segmentation has enabled impactful work in this context, it is limited by imaging quality and tissue heterogeneity. By contrast, recent array-based technologies offer the ability to measure the entire transcriptome at subcellular resolution across large samples3-6. Presently, there exist no approaches for cell type identification that directly leverage this information to annotate individual cells. Here we propose a multiscale approach to automatically classify cell types at this subcellular level, using both transcriptomic information and spatial context. We showcase this on both targeted and whole-transcriptome spatial platforms, improving cell classification and morphology for human kidney tissue and pinpointing individual sparsely distributed renal mouse immune cells without reliance on image data. By integrating these predictions into a topological pipeline based on multiparameter persistent homology7-9, we identify cell spatial relationships characteristic of a mouse model of lupus nephritis, which we validate experimentally by immunofluorescence. The proposed framework readily generalizes to new platforms, providing a comprehensive pipeline bridging different levels of biological organization from genes through to tissues.


Asunto(s)
Células , Perfilación de la Expresión Génica , Espacio Intracelular , Riñón , Transcriptoma , Animales , Femenino , Humanos , Ratones , Células/clasificación , Células/metabolismo , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica/métodos , Riñón/citología , Riñón/inmunología , Riñón/metabolismo , Riñón/patología , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , Nefritis Lúpica/metabolismo , Nefritis Lúpica/patología , Reproducibilidad de los Resultados , Espacio Intracelular/genética , Espacio Intracelular/metabolismo
2.
Mol Cell ; 73(2): 314-324.e4, 2019 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-30527663

RESUMEN

Macroautophagy/autophagy is a key catabolic recycling pathway that requires fine-tuned regulation to prevent pathologies and preserve homeostasis. Here, we report a new post-transcriptional pathway regulating autophagy involving the Pat1-Lsm (Lsm1 to Lsm7) mRNA-binding complex. Under nitrogen-starvation conditions, Pat1-Lsm binds a specific subset of autophagy-related (ATG) transcripts and prevents their 3' to 5' degradation by the exosome complex, leading to ATG mRNA stabilization and accumulation. This process is regulated through Pat1 dephosphorylation, is necessary for the efficient expression of specific Atg proteins, and is required for robust autophagy induction during nitrogen starvation. To the best of our knowledge, this work presents the first example of ATG transcript regulation via 3' binding factors and exosomal degradation.


Asunto(s)
Proteínas Relacionadas con la Autofagia/metabolismo , Autofagia , Nitrógeno/deficiencia , Proteínas de Unión a Caperuzas de ARN/metabolismo , Estabilidad del ARN , ARN de Hongos/metabolismo , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Regiones no Traducidas 3' , Proteínas Relacionadas con la Autofagia/genética , Sitios de Unión , Regulación Fúngica de la Expresión Génica , Humanos , Células Jurkat , Complejos Multiproteicos , Fosforilación , Unión Proteica , Proteínas de Unión a Caperuzas de ARN/genética , ARN de Hongos/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transducción de Señal
3.
Proc Natl Acad Sci U S A ; 121(16): e2315541121, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38598341

RESUMEN

Ferroptosis is an iron-dependent type of regulated cell death resulting from extensive lipid peroxidation and plays a critical role in various physiological and pathological processes. However, the regulatory mechanisms for ferroptosis sensitivity remain incompletely understood. Here, we report that homozygous deletion of Usp8 (ubiquitin-specific protease 8) in intestinal epithelial cells (IECs) leads to architectural changes in the colonic epithelium and shortens mouse lifespan accompanied by increased IEC death and signs of lipid peroxidation. However, mice with heterozygous deletion of Usp8 in IECs display normal phenotype and become resistant to azoxymethane/dextran sodium sulfate-induced colorectal tumorigenesis. Mechanistically, USP8 interacts with and deubiquitinates glutathione peroxidase 4 (GPX4), leading to GPX4 stabilization. Thus, USP8 inhibition destabilizes GPX4 and sensitizes cancer cells to ferroptosis in vitro. Notably, USP8 inhibition in combination with ferroptosis inducers retards tumor growth and enhances CD8+ T cell infiltration, which potentiates tumor response to anti-PD-1 immunotherapy in vivo. These findings uncover that USP8 counteracts ferroptosis by stabilizing GPX4 and highlight targeting USP8 as a potential therapeutic strategy to boost ferroptosis for enhancing cancer immunotherapy.


Asunto(s)
Ferroptosis , Neoplasias , Ratones , Animales , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Ferroptosis/genética , Homocigoto , Eliminación de Secuencia , Peroxidación de Lípido , Homeostasis , Neoplasias/genética , Neoplasias/terapia , Inmunoterapia
4.
Proc Natl Acad Sci U S A ; 120(43): e2304826120, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37844251

RESUMEN

Future food farming technology faces challenges that must integrate the core goal of keeping the global temperature increase within 1.5 °C without reducing food security and nutrition. Here, we show that boosting the production of insects and earthworms based on food waste and livestock manure to provide food and feed in China will greatly contribute to meeting the country's food security and carbon neutrality pledges. By substituting domestic products with mini-livestock (defined as earthworms and insects produced for food or feed) protein and utilizing the recovered land for bioenergy production plus carbon capture and storage, China's agricultural sector could become carbon-neutral and reduce feed protein imports to near zero. This structural change may lead to reducing greenhouse gas emissions by 2,350 Tg CO2eq per year globally when both domestic and imported products are substituted. Overall, the success of mini-livestock protein production in achieving carbon neutrality and food security for China and its major trading partners depends on how the substitution strategies will be implemented and how the recovered agricultural land will be managed, e.g., free use for afforestation and bioenergy or by restricting this land to food crop use. Using China as an example, this study also demonstrates the potential of mini-livestock for decreasing the environmental burden of food production in general.


Asunto(s)
Ganado , Eliminación de Residuos , Animales , Efecto Invernadero , Alimentos , Carbono , Biodiversidad , Temperatura , Agricultura , Seguridad Alimentaria , China
5.
Plant J ; 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38852163

RESUMEN

Sugarcane is the main source of sugar worldwide, and 80% of the sucrose production comes from sugarcane. However, the genetic differentiation and basis of agronomic traits remain obscure. Here, we sequenced the whole-genome of 219 elite worldwide sugarcane cultivar accessions. A total of approximately 6 million high-quality genome-wide single nucleotide polymorphisms (SNPs) were detected. A genome-wide association study identified a total of 2198 SNPs that were significantly associated with sucrose content, stalk number, plant height, stalk diameter, cane yield, and sugar yield. We observed homozygous tendency of favor alleles of these loci, and over 80% of cultivar accessions carried the favor alleles of the SNPs or haplotypes associated with sucrose content. Gene introgression analysis showed that the number of chromosome segments from Saccharum spontaneum decreased with the breeding time of cultivars, while those from S. officinarum increased in recent cultivars. A series of selection signatures were identified in sugarcane improvement procession, of which 104 were simultaneously associated with agronomic traits and 45 of them were mainly associated with sucrose content. We further proposed that as per sugarcane transgenic experiments, ShN/AINV3.1 plays a positive role in increasing stalk number, plant height, and stalk diameter. These findings provide comprehensive resources for understanding the genetic basis of agronomic traits and will be beneficial to germplasm innovation, screening molecular markers, and future sugarcane cultivar improvement.

6.
Br J Cancer ; 130(4): 597-612, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38184692

RESUMEN

BACKGROUND: The expression of Egl-9 family hypoxia-inducible factor 3 (EGLN3) is notably decreased in various malignancies, including gastric cancer (GC). While the predominant focus has been on the hydroxylase activity of EGLN3 for its antitumour effects, recent findings have suggested nonenzymatic roles for EGLN3. METHODS: This study assessed the clinical significance of EGLN3 expression in GC and explored the connection between EGLN3 DNA promoter methylation and transcriptional silencing. To investigate the effect of EGLN3 on GC cells, a gain-of-function strategy was adopted. RNA sequencing was conducted to identify the key effector molecules and signalling pathways associated with EGLN3. RESULTS: EGLN3 expression was significantly reduced in GC tissues, correlating with poorer patient prognosis. EGLN3 hypermethylation disrupts transcriptional equilibrium, contributing to deeper tumour invasion and lymph node metastasis, thus exacerbating GC progression. Conversely, restoration of EGLN3 expression in GC cells substantially inhibited cell proliferation and metastasis. EGLN3 was also found to impede the malignant progression of GC cells by downregulating Jumonji C domain-containing protein 8-mediated activation of the NF-κB pathway, independent of its hydroxylase activity. CONCLUSIONS: EGLN3 has the potential to hinder the spread of GC cells through a nonenzymatic mechanism, thereby shedding light on the complex nature of GC progression.


Asunto(s)
FN-kappa B , Neoplasias Gástricas , Humanos , FN-kappa B/genética , FN-kappa B/metabolismo , Neoplasias Gástricas/patología , Transducción de Señal/genética , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Oxigenasas de Función Mixta/genética , Línea Celular Tumoral , Proliferación Celular/genética , Prolina Dioxigenasas del Factor Inducible por Hipoxia/genética , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo
7.
J Neuroinflammation ; 21(1): 138, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802927

RESUMEN

Sepsis-associated encephalopathy (SAE) is a significant cause of mortality in patients with sepsis. Despite extensive research, its exact cause remains unclear. Our previous research indicated a relationship between non-hepatic hyperammonemia (NHH) and SAE. This study aimed to investigate the relationship between NHH and SAE and the potential mechanisms causing cognitive impairment. In the in vivo experimental results, there were no significant abnormalities in the livers of mice with moderate cecal ligation and perforation (CLP); however, ammonia levels were elevated in the hippocampal tissue and serum. The ELISA study suggest that fecal microbiota transplantation in CLP mice can reduce ammonia levels. Reduction in ammonia levels improved cognitive dysfunction and neurological impairment in CLP mice through behavioral, neuroimaging, and molecular biology studies. Further studies have shown that ammonia enters the brain to regulate the expression of aquaporins-4 (AQP4) in astrocytes, which may be the mechanism underlying brain dysfunction in CLP mice. The results of the in vitro experiments showed that ammonia up-regulated AQP4 expression in astrocytes, resulting in astrocyte damage. The results of this study suggest that ammonia up-regulates astrocyte AQP4 expression through the gut-brain axis, which may be a potential mechanism for the occurrence of SAE.


Asunto(s)
Acuaporina 4 , Astrocitos , Eje Cerebro-Intestino , Hiperamonemia , Encefalopatía Asociada a la Sepsis , Animales , Ratones , Acuaporina 4/metabolismo , Acuaporina 4/genética , Acuaporina 4/biosíntesis , Astrocitos/metabolismo , Hiperamonemia/metabolismo , Encefalopatía Asociada a la Sepsis/metabolismo , Masculino , Eje Cerebro-Intestino/fisiología , Ratones Endogámicos C57BL , Amoníaco/metabolismo , Amoníaco/sangre , Encéfalo/metabolismo , Trasplante de Microbiota Fecal
8.
Appl Environ Microbiol ; 90(4): e0174323, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38470180

RESUMEN

Soil and rhizosphere bacteria act as a rich source of secondary metabolites, effectively fighting against a diverse array of pathogens. Certain Pseudomonas species harbor biosynthetic gene clusters for producing both pyoluteorin and 2,4-diacetylphloroglucinol (2,4-DAPG), which are polyketides that exhibit highly similar antimicrobial spectrum against bacteria and fungi or oomycete. A complex cross talk exists between pyoluteorin and 2,4-DAPG biosynthesis, and production of 2,4-DAPG was strongly repressed by pyoluteorin, yet the underlying mechanism is still elusive. In this study, we find that the TetR family transcription factor PhlH is involved in the cross talk between pyoluteorin and 2,4-DAPG biosynthesis. PhlH binds to a palindromic sequence within the promoter of phlG (PphlG), which encodes a C-C bond hydrolase responsible for degrading 2,4-DAPG. As a signaling molecule, pyoluteorin disrupts the PhlH-PphlG complex by binding to PhlH, leading to decreased levels of 2,4-DAPG. Proteomics data suggest that pyoluteorin regulates multiple physiological processes including fatty acid biosynthesis and transportation of taurine, siderophore, and amino acids. Our work not only reveals a novel mechanism of cross talk between pyoluteorin and 2,4-DAPG biosynthesis, but also highlights pyoluteorin's role as a messenger in the complex communication network of Pseudomonas.IMPORTANCEAntibiosis serves as a crucial defense mechanism for microbes against invasive bacteria and resource competition. These bacteria typically orchestrate the production of multiple antibiotics in a coordinated fashion, wherein the synthesis of one antibiotic inhibits the generation of another. This strategic coordination allows the bacterium to focus its resources on producing the most advantageous antibiotic under specific circumstances. However, the underlying mechanisms of distinct antibiotic production in bacterial cells remain largely elusive. In this study, we reveal that the TetR family transcription factor PhlH detects the secondary metabolite pyoluteorin and mediates the cross talk between pyoluteorin and 2,4-DAPG biosynthesis in the biocontrol strain Pseudomonas protegens Pf-5. These findings hold promise for future research, potentially informing the manipulation of these systems to enhance the effectiveness of biocontrol agents.


Asunto(s)
Fenoles , Floroglucinol/análogos & derivados , Pseudomonas fluorescens , Pirroles , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación Bacteriana de la Expresión Génica , Pseudomonas/metabolismo , Antibacterianos/farmacología , Pseudomonas fluorescens/genética
9.
Cardiovasc Diabetol ; 23(1): 164, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724987

RESUMEN

Dynamin-related protein 1 (Drp1) is a crucial regulator of mitochondrial dynamics, the overactivation of which can lead to cardiovascular disease. Multiple distinct posttranscriptional modifications of Drp1 have been reported, among which S-nitrosylation was recently introduced. However, the detailed regulatory mechanism of S-nitrosylation of Drp1 (SNO-Drp1) in cardiac microvascular dysfunction in diabetes remains elusive. The present study revealed that mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4) was consistently upregulated in diabetic cardiomyopathy (DCM) and promoted SNO-Drp1 in cardiac microvascular endothelial cells (CMECs), which in turn led to mitochondrial dysfunction and cardiac microvascular disorder. Further studies confirmed that MAP4K4 promoted SNO-Drp1 at human C644 (mouse C650) by inhibiting glutathione peroxidase 4 (GPX4) expression, through which MAP4K4 stimulated endothelial ferroptosis in diabetes. In contrast, inhibition of MAP4K4 via DMX-5804 significantly reduced endothelial ferroptosis, alleviated cardiac microvascular dysfunction and improved cardiac dysfunction in db/db mice by reducing SNO-Drp1. In parallel, the C650A mutation in mice abolished SNO-Drp1 and the role of Drp1 in promoting cardiac microvascular disorder and cardiac dysfunction. In conclusion, our findings demonstrate that MAP4K4 plays an important role in endothelial dysfunction in DCM and reveal that SNO-Drp1 and ferroptosis activation may act as downstream targets, representing potential therapeutic targets for DCM.


Asunto(s)
Cardiomiopatías Diabéticas , Dinaminas , Células Endoteliales , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Células Cultivadas , Circulación Coronaria , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/genética , Cardiomiopatías Diabéticas/fisiopatología , Cardiomiopatías Diabéticas/patología , Cardiomiopatías Diabéticas/enzimología , Cardiomiopatías Diabéticas/etiología , Modelos Animales de Enfermedad , Dinaminas/metabolismo , Dinaminas/genética , Células Endoteliales/metabolismo , Células Endoteliales/patología , Células Endoteliales/enzimología , Células Endoteliales/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/patología , Mitocondrias Cardíacas/enzimología , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética
10.
BMC Cancer ; 24(1): 237, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383348

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignant tumor with strong invasiveness and poor prognosis. Previous studies have demonstrated the significant role of USP14 in various solid tumors. However, the role of USP14 in the regulation of HCC development and progression remains unclear. METHODS: We discovered through GEO and TCGA databases that USP14 may play an important role in liver cancer. Using bioinformatics analysis based on the Cancer Genome Atlas (TCGA) database, we screened and identified USP14 as highly expressed in liver cancer. We detected the growth and metastasis of HCC cells promoted by USP14 through clone formation, cell counting kit 8 assay, Transwell assay, and flow cytometry. In addition, we detected the impact of USP14 on the downstream protein kinase B (AKT) and epithelial-mesenchymal transition (EMT) pathways using western blotting. The interaction mechanism between USP14 and HK2 was determined using immunofluorescence and coimmunoprecipitation (CO-IP) experiments. RESULTS: We found that sh-USP14 significantly inhibits the proliferation, invasion, and invasion of liver cancer cells, promoting apoptosis. Further exploration revealed that sh-USP14 significantly inhibited the expression of HK2. Sh-USP14 can significantly inhibit the expression of AKT and EMT signals. Further verification through immunofluorescence and CO-IP experiments revealed that USP14 co-expressed with HK2. Further research has found that USP14 regulates the glycolytic function of liver cancer cells by the deubiquitination of HK2. USP14 regulates the autophagy function of liver cancer cells by regulating the interaction between SQSTM1/P62 and HK2. CONCLUSIONS: Our results indicate that USP14 plays a crucial role in the carcinogenesis of liver cancer. We also revealed the protein connections between USP14, HK2, and P62 and elucidated the potential mechanisms driving cancer development. The USP14/HK2/P62 axis may be a new therapeutic biomarker for the diagnosis and treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Transición Epitelial-Mesenquimal/genética , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo
11.
Cell Commun Signal ; 22(1): 93, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302971

RESUMEN

BACKGROUND: Physical exercise directly stretching the peripheral nerve promotes nerve regeneration; however, its action mechanism remains elusive. Our present study aimed to investigate the effects of mechanosensitive channel of large conductance (MscL) activated by mechanical stretching on the cultured Schwann cells (SCs) and explore the possible mechanism. METHODS: Primary SCs from neonatal mice at 3-5 days of age were derived and transfected with the lentivirus vector expressing a mutant version of MscL, MscL-G22S. We first detected the cell viability and calcium ion (Ca2+) influx in the MscL-G22S-expressing SCs with low-intensity mechanical stretching and the controls. Proteomic and energy metabolomics analyses were performed to investigate the comprehensive effects of MscL-G22S activation on SCs. Measurement of glycolysis- and oxidative phosphorylation-related molecules and ATP production were respectively performed to further validate the effects of MscL-G22S activation on SCs. Finally, the roles of phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway in the mechanism of energy metabolism modulation of SCs by MscL-G22S activation was investigated. RESULTS: Mechanical stretching-induced MscL-G22S activation significantly increased the cell viability and Ca2+ influx into the SCs. Both the proteomic and targeted energy metabolomics analysis indicated the upregulation of energy metabolism as the main action mechanism of MscL-G22S-activation on SCs. MscL-G22S-activated SCs showed significant upregulation of glycolysis and oxidative phosphorylation when SCs with stretching alone had only mild upregulation of energy metabolism than those without stimuli. MscL-G22S activation caused significant phosphorylation of the PI3K/AKT/mTOR signaling pathway and upregulation of HIF-1α/c-Myc. Inhibition of PI3K abolished the MscL-G22S activation-induced upregulation of HIF-1α/c-Myc signaling in SCs and reduced the levels of glycolysis- and oxidative phosphorylation-related substrates and mitochondrial activity. CONCLUSION: Mechanical stretching activates MscL-G22S to significantly promote the energy metabolism of SCs and the production of energic substrates, which may be applied to enhance nerve regeneration via the glia-axonal metabolic coupling.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Ratones , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Regulación hacia Arriba , Proteómica , Proteínas Proto-Oncogénicas c-myc/metabolismo , Glucólisis , Células de Schwann/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Estrés Oxidativo , Mamíferos/metabolismo
12.
Mol Pharm ; 21(2): 410-426, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38170627

RESUMEN

Cancer immunotherapy is a treatment method that activates or enhances the autoimmune response of the body to fight tumor growth and metastasis, has fewer toxic side effects and a longer-lasting efficacy than radiotherapy and chemotherapy, and has become an important means for the clinical treatment of cancer. However, clinical results from immunotherapy have shown that most patients lack responsiveness to immunotherapy and cannot benefit from this treatment strategy. The tumor microenvironment (TME) plays a critical role in the response to immunotherapy. The TME typically prevents effective lymphocyte activation, reducing their infiltration, and inhibiting the infiltration of effector T cells. According to the characteristic differences between the TME and normal tissues, various nanoplatforms with TME targeting and regulation properties have been developed for more precise regulation of the TME and have the ability to codeliver a variety of active pharmaceutical ingredients, thereby reducing systemic toxicity and improving the therapeutic effect of antitumor. In addition, the precise structural design of the nanoplatform can integrate specific functional motifs, such as surface-targeted ligands, degradable backbones, and TME stimulus-responsive components, into nanomedicines, thereby reshaping the tumor microenvironment, improving the body's immunosuppressive state, and enhancing the permeability of drugs in tumor tissues, in order to achieve controlled and stimulus-triggered release of load cargo. In this review, the physiological characteristics of the TME and the latest research regarding the application of TME-regulated nanoplatforms in improving antitumor immunotherapy will be described. Furthermore, the existing problems and further applications perspectives of TME-regulated platforms for cancer immunotherapy will also be discussed.


Asunto(s)
Neoplasias , Microambiente Tumoral , Humanos , Inmunoterapia , Medicamentos a Granel , Inmunosupresores , Neoplasias/tratamiento farmacológico
13.
Inorg Chem ; 63(15): 7063-7070, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38567746

RESUMEN

2D nanodendrites (NDs) and nanosheets (NSs) have been regarded as efficient nanocatalysts for enhancing the electrocatalytic performance due to their low coordinated sites and abundant electrocatalytic centers. Nevertheless, it remains challenging to construct advanced NDs and NSs in a single reaction system. Herein, by tuning the volume ratios of mixed solvents, the reduction and diffusion rate of Sn2+ on Pd NSs template was rationally controlled to prepare PdSn NDs and PdSn NSs. Ascribed to the open 2D nanostructure, high specific surface area, and robust synergistic effect, the as-prepared PdSn NDs and PdSn NSs exhibited distinguished electrocatalytic activities for ethylene glycol oxidation reaction (EGOR) and ethanol oxidation reaction (EOR), as well as commendable electrocatalytic durability, which were far superior to the Pd NSs and commercial Pd/C. In addition, the PdSn NDs exhibited enhanced reaction kinetics because the characteristic branch structure exposed a high density of active sites. This work may provide significant guidance for preparing excellent nanocatalysts with various morphological features by simply optimizing the content of the coexisting solvents.

14.
Inorg Chem ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39038173

RESUMEN

By utilizing Metal-organic framework (MOF) materials as a base, constructing electrocatalysts with heterogeneous structures offers advantages for catalyzing water splitting. In this study, a hollow heterogeneous nanocatalyst, Ir-MIL-88A@NiFe-LDHs, was prepared by growing a layered double hydroxides (LDHs) shell on MIL-88A substrate. The catalyst shows excellent oxygen evolution reaction (OER) performance in a 1.0 M KOH solution, requiring only 217 mV overpotential to achieve a current density of 10 mA cm-2 with a Tafel slope of 62.18 mV dec-1, indicating significant electrocatalytic performance and reaction kinetics characteristics. Furthermore, long-term OER testing also demonstrates the catalyst's outstanding stability. Emphasizing the interfacial interaction between MOF and LDHs, as well as the synergistic effect among Ni, Fe, and Ir elements, the study highlights how these factors collaboratively control the local electronic structure of the hollow Ir-MIL-88A@NiFe-LDHs, resulting in an efficient MOF-derived electrocatalyst.

15.
Acta Biochim Biophys Sin (Shanghai) ; 56(5): 709-716, 2024 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-38655615

RESUMEN

SLC45A1 encodes a glucose transporter protein highly expressed in the brain. Mutations in SLC45A1 may lead to neurological diseases and developmental disorders, but its exact role is poorly understood. DNA G-quadruplexes (DNA G4s) are stable structures formed by four guanine bases and play a role in gene regulation and genomic stability. Changes in DNA G4s may affect brain development and function. The mechanism linking alterations in DNA G-quadruplex structures to SLC45A1 pathogenicity remains unknown. In this study, we identify a functional DNA G-quadruplex and its key binding site on SLC45A1 (NM_001080397.3: exon 2: c.449 G>A: p.R150K). This variant results in the upregulation of mRNA and protein expression, which may lead to intellectual developmental disorder with neuropsychiatric features. Mechanistically, the mutation is found to disrupt DNA G-quadruplex structures on SLC45A1, leading to transcriptional enhancement and a gain-of-function mutation, which further causes increased expression and function of the SLC45A1 protein. The identification of the functional DNA G-quadruplex and its effects on DNA G4s may provide new insights into the genetic basis of SLC45A1 pathogenicity and highlight the importance of DNA G4s of SLC45A1 in regulating gene expression and brain development.


Asunto(s)
Discapacidades del Desarrollo , G-Cuádruplex , Humanos , Discapacidades del Desarrollo/genética , Mutación con Ganancia de Función , Células HEK293 , Sitios de Unión/genética
16.
Ecotoxicol Environ Saf ; 272: 116020, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38306816

RESUMEN

Cadmium is a persistent heavy metal commonly found in aquatic ecosystems and has a strong toxic effect on organisms. The sensitivity of phytoplankton to environmental changes and its role as an indicator of aquatic ecosystem health have been well-established. However, the mechanisms by which phytoplankton respond to cadmium remain incompletely understood. In this study, we chose the typical planktonic diatom Cyclotella meneghiniana Kützing, by integrating physiological-biochemical data and transcriptome analysis, to reveal the molecular mechanisms of C. meneghiniana responing to cadmium. Under cadmium stress, the cell density and chlorophyll-a content of C. meneghiniana significantly decreased, while MDA content and SOD activity gradually increased. At 72 h of cadmium stress, we found that at this time point, cell abundance and physiological variation were very significant, therefore we selected 72 h for subsequent analysis. To better understand the cadmium stress response mechanisms of C. meneghiniana, a de novo transcriptome method was used to analyse C. meneghiniana under cadmium stress for 72 h, and 1704 (M vs. CK) and 4788 (H vs. CK) differentially expressed genes were found. Our results showed that the changes in gene expression were closely correlated to the physiological-biochemical changes. Although cadmium stress could promote the nitrogen metabolism pathway, ROS scavenging system, and photosynthesis. While, C. meneghiniana under medium and high concentrations of cadmium can also limit various intracellular metabolic pathways, such as the MAPK pathway and phosphatidylinositol metabolic pathway, and the degree of inhibition increases with the increase of stress concentration. In present study, the complete molecular mechanism of the planktonic diatom response to cadmium has been established, which provided important information for further studies on heavy metal pollutants and the multiple functional genes responsible for cadmium sensitivity and tolerance in planktonic diatoms.


Asunto(s)
Cadmio , Diatomeas , Cadmio/metabolismo , Ecosistema , Transcriptoma , Fotosíntesis , Plancton , Fitoplancton
17.
Sensors (Basel) ; 24(7)2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38610551

RESUMEN

As an indispensable component of coal-fired power plants, boilers play a crucial role in converting water into high-pressure steam. The oxygen content in the flue gas is a crucial indicator, which indicates the state of combustion within the boiler. The oxygen content not only affects the thermal efficiency of the boiler and the energy utilization of the generator unit, but also has adverse impacts on the environment. Therefore, accurate measurement of the flue gas's oxygen content is of paramount importance in enhancing the energy utilization efficiency of coal-fired power plants and reducing the emissions of waste gas and pollutants. This study proposes a prediction model for the oxygen content in the flue gas that combines the whale optimization algorithm (WOA) and long short-term memory (LSTM) networks. Among them, the whale optimization algorithm (WOA) was used to optimize the learning rate, the number of hidden layers, and the regularization coefficients of the long short-term memory (LSTM). The data used in this study were obtained from a 350 MW power generation unit in a coal-fired power plant to validate the practicality and effectiveness of the proposed hybrid model. The simulation results demonstrated that the whale optimization algorithm-long short-term memory (WOA-LSTM) model achieved an MAE of 0.16493, an RMSE of 0.12712, an MAPE of 2.2254%, and an R2 value of 0.98664. The whale optimization algorithm-long short-term memory (WOA-LSTM) model demonstrated enhancements in accuracy compared with the least squares support vector machine (LSSVM), long short-term memory (LSTM), particle swarm optimization-least squares support vector machine (PSO-LSSVM), and particle swarm optimization-long short-term memory (PSO-LSTM), with improvements of 4.93%, 4.03%, 1.35%, and 0.49%, respectively. These results indicated that the proposed soft sensor model exhibited more accurate performance, which can meet practical requirements of coal-fired power plants.

18.
Sensors (Basel) ; 24(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38400426

RESUMEN

This study investigates the application of hyperspectral image space-spectral fusion technology in lithologic classification, using data from China's GF-5 and Europe's Sentinel-2A. The research focuses on the southern region of Tuanjie Peak in the Western Kunlun Range, comparing five space-spectral fusion methods: GSA, SFIM, CNMF, HySure, and NonRegSRNet. To comprehensively evaluate the effectiveness and applicability of these fusion methods, the study conducts a comprehensive assessment from three aspects: evaluation of fusion effects, lithologic classification experiments, and field validation. In the evaluation of fusion effects, the study uses an index analysis and comparison of spectral curves before and after fusion, concluding that the GSA fusion method performs the best. For lithologic classification, the Random Forest (RF) classification method is used, training with both area and point samples. The classification results from area sample training show significantly higher overall accuracy compared to point samples, aligning well with 1:50,000 scale geological maps. In field validation, the study employs on-site verification combined with microscopic identification and comparison of images with actual spectral fusion, finding that the classification results for the five lithologies are essentially consistent with field validation results. The "GSA+RF" method combination established in this paper, based on data from GF-5 and Sentinel-2A satellites, can provide technical support for lithological classification in similar high-altitude regions.

19.
Genes Dev ; 30(12): 1409-22, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27313316

RESUMEN

Aging is a risk factor for many human pathologies and is characterized by extensive metabolic changes. Using targeted high-throughput metabolite profiling in Drosophila melanogaster at different ages, we demonstrate that methionine metabolism changes strikingly during aging. Methionine generates the methyl donor S-adenosyl-methionine (SAM), which is converted via methylation to S-adenosyl-homocysteine (SAH), which accumulates during aging. A targeted RNAi screen against methionine pathway components revealed significant life span extension in response to down-regulation of two noncanonical Drosophila homologs of the SAH hydrolase Ahcy (S-adenosyl-L-homocysteine hydrolase [SAHH[), CG9977/dAhcyL1 and Ahcy89E/CG8956/dAhcyL2, which act as dominant-negative regulators of canonical AHCY. Importantly, tissue-specific down-regulation of dAhcyL1/L2 in the brain and intestine extends health and life span. Furthermore, metabolomic analysis of dAhcyL1-deficient flies revealed its effect on age-dependent metabolic reprogramming and H3K4 methylation. Altogether, reprogramming of methionine metabolism in young flies and suppression of age-dependent SAH accumulation lead to increased life span. These studies highlight the role of noncanonical Ahcy enzymes as determinants of healthy aging and longevity.


Asunto(s)
Envejecimiento/metabolismo , Regulación hacia Abajo , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiología , Péptidos y Proteínas de Señalización Intracelular/genética , Longevidad/genética , Animales , Encéfalo/enzimología , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Drosophila melanogaster/genética , Femenino , Heterocromatina/genética , Intestinos/enzimología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Metionina/metabolismo , Metilación , S-Adenosilhomocisteína
20.
J Biol Chem ; 298(6): 102027, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35568198

RESUMEN

The production of secondary metabolites is a major mechanism used by beneficial rhizobacteria to antagonize plant pathogens. These bacteria have evolved to coordinate the production of different secondary metabolites due to the heavy metabolic burden imposed by secondary metabolism. However, for most secondary metabolites produced by bacteria, it is not known how their biosynthesis is coordinated. Here, we showed that PhlH from the rhizobacterium Pseudomonas fluorescens is a TetR-family regulator coordinating the expression of enzymes related to the biosynthesis of several secondary metabolites, including 2,4-diacetylphloroglucinol (2,4-DAPG), mupirocin, and pyoverdine. We present structures of PhlH in both its apo form and 2,4-DAPG-bound form and elucidate its ligand-recognizing and allosteric switching mechanisms. Moreover, we found that dissociation of 2,4-DAPG from the ligand-binding domain of PhlH was sufficient to allosterically trigger a pendulum-like movement of the DNA-binding domains within the PhlH dimer, leading to a closed-to-open conformational transition. Finally, molecular dynamics simulations confirmed that two distinct conformational states were stabilized by specific hydrogen bonding interactions and that disruption of these hydrogen bonds had profound effects on the conformational transition. Our findings not only reveal a well-conserved route of allosteric signal transduction in TetR-family regulators but also provide novel mechanistic insights into bacterial metabolic coregulation.


Asunto(s)
Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Pseudomonas fluorescens , Transducción de Señal , Proteínas Bacterianas/metabolismo , Proteínas de Unión al ADN/metabolismo , Enlace de Hidrógeno , Ligandos , Mupirocina/metabolismo , Oligopéptidos/metabolismo , Floroglucinol/metabolismo , Conformación Proteica , Pseudomonas fluorescens/metabolismo , Metabolismo Secundario
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