534 research outputs found

    A reversible phospho-switch mediated by ULK1 regulates the activity of autophagy protease ATG4B

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    Upon induction of autophagy, the ubiquitin-like protein LC3 is conjugated to phosphatidylethanolamine (PE) on the inner and outer membrane of autophagosomes to allow cargo selection and autophagosome formation. LC3 undergoes two processing steps, the proteolytic cleavage of pro-LC3 and the de-lipidation of LC3-PE from autophagosomes, both executed by the same cysteine protease ATG4. How ATG4 activity is regulated to co-ordinate these events is currently unknown. Here we find that ULK1, a protein kinase activated at the autophagosome formation site, phosphorylates human ATG4B on serine 316. Phosphorylation at this residue results in inhibition of its catalytic activity in vitro and in vivo. On the other hand, phosphatase PP2A-PP2R3B can remove this inhibitory phosphorylation. We propose that the opposing activities of ULK1-mediated phosphorylation and PP2A-mediated dephosphorylation provide a phospho-switch that regulates the cellular activity of ATG4B to control LC3 processing

    Комплексные соединения галогенидов цинка как потенциальные противораковые препараты

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    The purpose of this review is to summarize currently available evidence implicating vitamin K in the pathogenesis of vascular calcification (VC), in particular arterial medial calcification. In doing so, we try to provide a rationale for an interventional clinical study testing whether vitamin K supplementation can retard VC or even affect cardiovascular mortality in chronic kidney disease patients. Additionally, we wish to give an overview of the current literature indicating potential adverse effects of long-term vitamin K antagonists in this population

    Systematic Identification of Oncogenic EGFR Interaction Partners

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    The Epidermal Growth Factor Receptor (EGFR) is a receptor tyrosine kinase that - once activated upon ligand binding - leads to receptor dimerization, recruitment of protein complexes and activation of multiple signaling cascades. The EGFR is frequently overexpressed or mutated in various cancers leading to aberrant signaling and tumor growth. Hence, identification of interaction partners that bind to mutated EGFR can help identify novel targets for drug discovery. Here, we used a systematic approach to identify novel proteins that are involved in cancerous EGFR-signaling. Using a combination of high-content imaging and a mammalian membrane two-hybrid protein-protein interaction (MaMTH) method, we identified 8 novel interaction partners of EGFR, out of which half strongly interacted with oncogenic, hyperactive EGFR variants. One of these, TACC3, stabilizes EGFR on the cell surface, which results in an increase in downstream signaling via the MAPK and AKT pathway. Depletion of TACC3 from cells using shRNA knockdown or small molecule targeting reduced mitogenic signaling in non-small cell lung cancer cell lines, suggesting that targeting TACC3 has potential as a new therapeutic approach for non-small cell lung cancer

    Modulation of endothelial organelle size as an antithrombotic strategy

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    BACKGROUND: It is long-established that Von Willebrand Factor (VWF) is central to haemostasis and thrombosis. Endothelial VWF is stored in cell-specific secretory granules, Weibel-Palade bodies (WPBs), organelles generated in a wide range of lengths (0.5 to 5.0 μm). WPB size responds to physiological cues and pharmacological treatment, and VWF secretion from shortened WPBs dramatically reduces platelet and plasma VWF adhesion to an endothelial surface. OBJECTIVE: We hypothesised that WPB-shortening represented a novel target for antithrombotic therapy. Our objective was to determine whether compounds exhibiting this activity do exist. METHODS: Using a microscopy approach coupled to automated image analysis, we measured the size of WPB bodies in primary human endothelial cells treated with licensed compounds for 24 h. RESULTS AND CONCLUSIONS: A novel approach to identification of antithrombotic compounds generated a significant number of candidates with the ability to shorten WPBs. In vitro assays of two selected compounds confirm that they inhibit the pro-haemostatic activity of secreted VWF. This set of compounds acting at a very early stage of the haemostatic process could well prove to be a useful adjunct to current antithrombotic therapeutics. Further, in the current SARS-CoV-2 pandemic, with a considerable fraction of critically ill COVID-19 patients affected by hypercoagulability, these WPB size-reducing drugs might also provide welcome therapeutic leads for frontline clinicians and researchers

    Improving business processes of service companies

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    This article considers the problem of improving business process through analysis “Highlighting areas of concern”. In the process, we formulated a number of requirements that should meet the functionality of the information system and highlighted advantages of the"Selection concerns" method

    Manufacturing improvements project and its impact on financial outcome

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    In response to changes in the external conditions of the oil and gas processing industry, the requirements for the equipment of the oil refinery are forced to change, which calls for the implementation of investment projects. The article considers the data on the implementation of the project for the reconstruction of the primary oil refinery, shows its main technical and economic indicators, examines the direction of the project's impact on the financial performance of the enterprise as a whole

    A Two-Tier Golgi-Based Control of Organelle Size Underpins the Functional Plasticity of Endothelial Cells

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    Weibel-Palade bodies (WPBs), endothelial-specific secretory granules that are central to primary hemostasis and inflammation, occur in dimensions ranging between 0.5 and 5 μm. How their size is determined and whether it has a functional relevance are at present unknown. Here, we provide evidence for a dual role of the Golgi apparatus in controlling the size of these secretory carriers. At the ministack level, cisternae constrain the size of nanostructures (“quanta”) of von Willebrand factor (vWF), the main WPB cargo. The ribbon architecture of the Golgi then allows copackaging of a variable number of vWF quanta within the continuous lumen of the trans-Golgi network, thereby generating organelles of different sizes. Reducing the WPB size abates endothelial cell hemostatic function by drastically diminishing platelet recruitment, but, strikingly, the inflammatory response (the endothelial capacity to engage leukocytes) is unaltered. Size can thus confer functional plasticity to an organelle by differentially affecting its activities

    Identification and functional validation of FDA-approved positive and negative modulators of the mitochondrial calcium uniporter

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    The mitochondrial calcium uniporter (MCU), the highly selective channel responsible for mitochondrial Ca2+ entry, plays important roles in physiology and pathology. However, only few pharmacological compounds directly and selectively modulate its activity. Here, we perform high-throughput screening on a US Food and Drug Administration (FDA)-approved drug library comprising 1,600 compounds to identify molecules modulating mitochondrial Ca2+ uptake. We find amorolfine and benzethonium to be positive and negative MCU modulators, respectively. In agreement with the positive effect of MCU in muscle trophism, amorolfine increases muscle size, and MCU silencing is sufficient to blunt amorolfine-induced hypertrophy. Conversely, in the triple-negative breast cancer cell line MDA-MB-231, benzethonium delays cell growth and migration in an MCU-dependent manner and protects from ceramide-induced apoptosis, in line with the role of mitochondrial Ca2+ uptake in cancer progression. Overall, we identify amorolfine and benzethonium as effective MCU-targeting drugs applicable to a wide array of experimental and disease conditions

    Технологические решения для строительства разведочной вертикальной скважины глубиной 2750 метров на нефтяном месторождении (ХМАО)

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    Технологические решения для строительства разведочной вертикальной скважины глубиной 2750 метров на нефтяном месторождении (ХМАО).Technological solutions for the construction of an exploration vertical well with a depth of 2,750 meters at the oil field (KhMAO)
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