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1.
Cell ; 155(6): 1258-69, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24290358

RESUMO

Molecular determinants regulating the activation of class B G-protein-coupled receptors (GPCRs) by native peptide agonists are largely unknown. We have investigated here the interaction between the corticotropin releasing factor receptor type 1 (CRF1R) and its native 40-mer peptide ligand Urocortin-I directly in mammalian cells. By incorporating unnatural amino acid photochemical and new click-chemical probes into the intact receptor expressed in the native membrane of live cells, 44 intermolecular spatial constraints have been derived for the ligand-receptor interaction. The data were analyzed in the context of the recently resolved crystal structure of CRF1R transmembrane domain and existing extracellular domain structures, yielding a complete conformational model for the peptide-receptor complex. Structural features of the receptor-ligand complex yield molecular insights on the mechanism of receptor activation and the basis for discrimination between agonist and antagonist function.


Assuntos
Modelos Moleculares , Receptores de Hormônio Liberador da Corticotropina/química , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Urocortinas/química , Urocortinas/metabolismo , Sequência de Aminoácidos , Animais , Química Click/métodos , Reagentes de Ligações Cruzadas/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Ratos , Receptores de Hormônio Liberador da Corticotropina/genética , Alinhamento de Sequência
2.
PLoS Genet ; 20(5): e1011282, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38768261

RESUMO

Light as a source of information regulates morphological and physiological processes of fungi, including development, primary and secondary metabolism, or the circadian rhythm. Light signaling in fungi depends on photoreceptors and downstream components that amplify the signal to govern the expression of an array of genes. Here, we investigated the effects of red and far-red light in the mycoparasite Trichoderma guizhouense on its mycoparasitic potential. We show that the invasion strategy of T. guizhouense depends on the attacked species and that red and far-red light increased aerial hyphal growth and led to faster overgrowth or invasion of the colonies. Molecular experiments and transcriptome analyses revealed that red and far-red light are sensed by phytochrome FPH1 and further transmitted by the downstream MAPK HOG pathway and the bZIP transcription factor ATF1. Overexpression of the red- and far-red light-induced fluffy gene fluG in the dark resulted in abundant aerial hyphae formation and thereby improvement of its antagonistic ability against phytopathogenic fungi. Hence, light-induced fluG expression is important for the mycoparasitic interaction. The increased aggressiveness of fluG-overexpressing strains was phenocopied by four random mutants obtained after UV mutagenesis. Therefore, aerial hyphae formation appears to be a trait for the antagonistic potential of T. guizhouense.


Assuntos
Regulação Fúngica da Expressão Gênica , Hifas , Luz , Fitocromo , Trichoderma , Hifas/crescimento & desenvolvimento , Hifas/genética , Fitocromo/metabolismo , Fitocromo/genética , Trichoderma/genética , Trichoderma/fisiologia , Trichoderma/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Rhizoctonia/crescimento & desenvolvimento , Luz Vermelha
3.
Cell ; 144(5): 703-18, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21376233

RESUMO

Among breast cancers, triple-negative breast cancer (TNBC) is the most poorly understood and is refractory to current targeted therapies. Using a genetic screen, we identify the PTPN12 tyrosine phosphatase as a tumor suppressor in TNBC. PTPN12 potently suppresses mammary epithelial cell proliferation and transformation. PTPN12 is frequently compromised in human TNBCs, and we identify an upstream tumor-suppressor network that posttranscriptionally controls PTPN12. PTPN12 suppresses transformation by interacting with and inhibiting multiple oncogenic tyrosine kinases, including HER2 and EGFR. The tumorigenic and metastatic potential of PTPN12-deficient TNBC cells is severely impaired upon restoration of PTPN12 function or combined inhibition of PTPN12-regulated tyrosine kinases, suggesting that TNBCs are dependent on the proto-oncogenic tyrosine kinases constrained by PTPN12. Collectively, these data identify PTPN12 as a commonly inactivated tumor suppressor and provide a rationale for combinatorially targeting proto-oncogenic tyrosine kinases in TNBC and other cancers based on their profile of tyrosine-phosphatase activity.


Assuntos
Neoplasias da Mama/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 12/genética , Proteína Tirosina Fosfatase não Receptora Tipo 12/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Mutação , Metástase Neoplásica , Processamento de Proteína Pós-Traducional
4.
Plant J ; 120(1): 335-353, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39167539

RESUMO

12-Oxo-phytodienoic acid reductases (OPRs) perform vital functions in plants. However, few studies have been reported in sugarcane (Saccharum spp.), and it is of great significance to systematically investigates it in sugarcane. Here, 61 ShOPRs, 32 SsOPRs, and 36 SoOPRs were identified from R570 (Saccharum spp. hybrid cultivar R570), AP85-441 (Saccharum spontaneum), and LA-purple (Saccharum officinarum), respectively. These OPRs were phylogenetically classified into four groups, with close genes similar structures. During evolution, OPR gene family was mainly expanded via whole-genome duplications/segmental events and predominantly underwent purifying selection, while sugarcane OPR genes may function differently in response to various stresses. Further, ScOPR2, a tissue-specific OPR, which was localized in cytoplasm and cell membrane and actively response to salicylic acid (SA), methyl jasmonate, and smut pathogen (Sporisorium scitamineum) stresses, was cloned from sugarcane. In addition, both its transient overexpression and stable overexpression enhanced the resistance of transgenic plants to pathogen infection, most probably through activating pathogen-associated molecular pattern/pattern-recognition receptor-triggered immunity, producing reactive oxygen species, and initiating mitogen-activated protein kinase cascade. Subsequently, the transmission of SA and hypersensitive reaction were triggered, which stimulated the transcription of defense-related genes. These findings provide insights into the function of ScOPR2 gene for disease resistance.


Assuntos
Resistência à Doença , Regulação da Expressão Gênica de Plantas , Filogenia , Doenças das Plantas , Proteínas de Plantas , Saccharum , Saccharum/genética , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Família Multigênica , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Plantas Geneticamente Modificadas , Ácido Salicílico/metabolismo , Ciclopentanos/metabolismo , Ustilaginales/fisiologia , Ustilaginales/genética , Genes de Plantas/genética , Acetatos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH
5.
Anal Chem ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023238

RESUMO

The adjustment of the emission wavelengths and cell permeability of the perylene diimides (PDI) for multicolor cell imaging is a great challenge. Herein, based on a bay-region substituent engineering strategy, multicolor perylene diimides (MCPDI) were rationally designed and synthesized by introducing azetidine substituents on the bay region of PDIs. With the fine-tuned electron-donating ability of the azetidine substituents, these MCPDI showed high brightness, orange, red, and near infrared (NIR) fluorescence along with Stokes shifts increasing from 35 to 110 nm. Interestingly, azetidine substituents distorted to the plane of the MCPDI dyes, and the twist angle of monosubstituted MCPDI was larger than that of disubstituted MCPDI, which might efficiently decrease their π-π stacking. Moreover, all of these MCPDI dyes were cell-permeable and selectively stained various organelles for multicolor imaging of multiple organelles in living cells. Two-color imaging of lipid droplets (LDs) and other organelles stained with MCPDI dyes was performed to reveal the interaction between the LDs and other organelles in living cells. Furthermore, a NIR-emitting MCPDI dye with a mitochondria-targeted characteristic was successfully applied for tumor-specific imaging. The facile synthesis, excellent stability, high brightness, tunable fluorescence emission, and Stokes shifts make these MCPDI promising fluorescent probes for biological applications.

6.
Small ; 20(11): e2305889, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939307

RESUMO

The development of highly active and acid-stable electrocatalysts for oxygen evolution reaction (OER) is of great significance for water electrolysis technology. Herein, a highly efficient molybdenum-doped mesoporous ruthenium dioxide sphere (Mo-RuO2 ) catalyst is fabricated by a facile impregnation and post-calcination method using mesoporous carbon spheres to template the mesostructure. The optimal Mo0.15 -RuO2 catalyst with Mo doping amount of 15 mol.% exhibits a significantly low overpotential of 147 mV at 10 mA cm-2 , a small Tafel slope of 38 mV decade-1 , and enhanced electrochemical stability in acidic electrolyte, far superior to the commercial RuO2 catalyst. The experimental results and theoretical analysis reveal that the remarkable electrocatalytic performance can be attributed to the large surface area of the mesoporous spherical structure, the structural robustness of the interconnected mesoporous framework, and the change in the electronic structure of Ru active sites induced by Mo doping. These excellent advantages make Mo-doped mesoporous RuO2 spheres a promising catalyst for highly efficient electrocatalytic OER in acidic media.

7.
Small ; : e2403490, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39031997

RESUMO

The miniaturization, integration, and increased power of electronic devices have exacerbated serious heat dissipation issues. Thermally conductive adhesives, which effectively transfer heat and firmly bond components, are critical for addressing these challenges. This paper innovatively proposed a composite comprising inorganic phosphate/alumina as a matrix and diamond as filler. The composite achieved an isotropic thermal conductivity (TC) of up to 18.96 W m-1 K-1, significantly surpassing existing reports while maintaining electrical insulation. First-principles calculations and experimental tests confirmed that the high TC of phosphate and excellent interface contact ensured efficient heat transfer. To optimize bonding performance, a modified-diamond/Al(H2PO4)3@epoxy hybrid composite is subsequently developed using an organic modification method. The unique hybrid structure, combining inorganic thermal pathways and an organic adhesive network, enabled the hybrid composite to simultaneously possess a high TC (3.23 W m-1 K-1) and strong adhesion (14.35 MPa). Compared to previous reports, the comprehensive performance of this hybrid thermally conductive adhesive is exceptionally remarkable. The superior heat dissipation capability of the hybrid thermal adhesive is demonstrated in chip cooling scenarios. This organic/inorganic hybrid approach offered a new direction for obtaining advanced thermal interface materials, demonstrating significant application potential in chip soldering, packaging, and heat dissipation.

8.
Small ; 20(15): e2307743, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009525

RESUMO

Herein, a series of imine-linked covalent organic frameworks (COFs) are developed with advanced ordered mesoporous hollow spherical nanomorphology and ultra-large mesopores (4.6 nm in size), named OMHS-COF-M (M = H, Co, and Ni). The ordered mesoporous hollow spherical nanomorphology is revealed to be formed via an Ostwald ripening mechanism based on a one-step self-templated strategy. Encouraged by its unique structural features and outstanding photoelectrical property, the OMHS-COF-Co material is applied as the photocatalyst for CO2-to-CO reduction. Remarkably, it delivers an impressive CO production rate as high as 15 874 µmol g-1 h-1, a large selectivity of 92.4%, and a preeminent cycling stability. From in/ex situ experiments and density functional theory (DFT) calculations, the excellent CO2 photoreduction performance is ascribed to the desirable cooperation of unique ordered mesoporous hollow spherical host and abundant isolated Co active sites, enhancing CO2 activation, and improving electron transfer kinetics as well as reducing the energy barriers for intermediates *COOH generation and CO desorption.

9.
Plant Biotechnol J ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899717

RESUMO

Rapeseed (Brassica napus) silique is the major carbohydrate source for seed development, and the final silique length has attracted great attention from breeders. However, no studies had focused on the dynamic character of silique elongation length (SEL). Here, the dynamic SEL investigation in a natural population including 588 lines over two years indicate that dynamic SEL during 0-20 days after flowering was the most essential stage associated with seed number per silique (SPS) and thousand seed weight (TSW). Then, nine loci were identified to be associated with SEL based on GWAS analysis, among which five SNPs (over 50%) distributed on the A02 chromosome within 6.08 to 6.48 Mb. Subsequently, we screened 5078 differentially expressed genes between two extreme materials. An unknown protein, BnaA02.SE, was identified combining with GWAS and RNA-Seq analysis. Subcellular localization and expression profiles analysis demonstrated that BnaA02.SE is a chloroplast- and nucleus-localized protein mainly expressed in pericarps and leaves. Furthermore, transgenic verification and dynamic cytological observation reveal that overexpressed BnaA02.SE can promote silique elongation by regulating JA and IAA contents, affecting cell proliferation and expansion, respectively, and finally enhance seed yield by influencing SPS and TSW. Haplotype analysis reveal that the homologs of BnaA02.SE may also be involved in silique elongation regulation. Our findings provided comprehensive insights into a newly SEL trait, and cloned the first gene (BnaA02.SE) controlling silique elongation in B. napus. The identified BnaA02.SE and its homologs can offer a valuable target for improving B. napus yield.

10.
Mol Ecol ; 33(4): e17249, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38133544

RESUMO

Understanding the mechanisms underlying diapause formation is crucial for gaining insight into adaptive survival strategies across various species. In this study, we aimed to uncover the pivotal role of temperature and food availability in regulating diapausing podocyst formation in the jellyfish Aurelia coerulea. Furthermore, we explored the cellular and molecular basis of diapause formation using single-cell RNA sequencing. Our results showed cell-type-specific transcriptional landscapes during podocyst formation, which were underscored by the activation of specific transcription factors and signalling pathways. In addition, we found that the heat shock protein-coding genes HSC70 and HSP90a potentially act as hub genes that regulate podocyst formation. Finally, we mapped the single-cell atlas of diapausing podocysts and identified cell types involved in metabolism, environmental sensing, defence and development that may collectively contribute to the long-term survival and regulated excystment of diapausing podocysts. Taken together, the findings of this study provide novel insights into the molecular mechanisms that regulate diapause formation and contributes to a better understanding of adaptive survival strategies in a variety of ecological contexts.


Assuntos
Diapausa , Cifozoários , Animais , Cifozoários/genética , Temperatura , Diapausa/genética
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