1,618 results match your criteria cytosol sufficient

Structural and functional analysis of tomato sterol C22 desaturase.

BMC Plant Biol 2021 Mar 17;21(1):141. Epub 2021 Mar 17.

Center for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Barcelona, Spain.

Background: Sterols are structural and functional components of eukaryotic cell membranes. Plants produce a complex mixture of sterols, among which β-sitosterol, stigmasterol, campesterol, and cholesterol in some Solanaceae, are the most abundant species. Many reports have shown that the stigmasterol to β-sitosterol ratio changes during plant development and in response to stresses, suggesting that it may play a role in the regulation of these processes. Read More

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The cytotoxic effect of Clostridioides difficile pore-forming toxin CDTb.

Biochim Biophys Acta Biomembr 2021 Jun 6;1863(6):183603. Epub 2021 Mar 6.

Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany.

Clostridioides (C.) difficile is clinically highly relevant and produces several AB-type protein toxins, which are the causative agents for C. difficile-associated diarrhea and pseudomembranous colitis. Read More

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Quetiapine promotes oligodendroglial process outgrowth and membrane expansion by orchestrating the effects of Olig1.

Glia 2021 Mar 4. Epub 2021 Mar 4.

Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, China.

Oligodendroglial lineage cells go through a series of morphological changes before myelination. Prior to myelination, cell processes and membrane structures enlarge by approximately 7,000 times, which is required to support axonal wrapping and myelin segment formation. Failure of these processes leads to maldevelopment and impaired myelination. Read More

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MiT/TFE family members suppress L-leucyl-L-leucine methyl ester-induced cell death.

J Toxicol Sci 2021 ;46(3):143-156

Graduate School of Biomedical and Health Sciences, Hiroshima University.

Lysosomes are degradative organelles essential for cell homeostasis. However, various internal and external stimuli, including L-leucyl-L-leucine methyl ester (LLOMe), which is one of the common lysosomotropic agents, permeabilize the lysosomal membrane, leading to lysosome-dependent cell death because of leakage of lysosomal contents to the cytosol. The microphthalmia/transcription factor E (MiT/TFE) family members, which include transcription factor EB (TFEB), transcription factor E3 (TFE3), and microphthalmia-associated transcription factor (MITF), are master regulators of lysosomal biogenesis and are known to be involved in the lysosomal stress response. Read More

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January 2021

MenI encodes a DHNA-CoA thioesterase necessary for menaquinone biosynthesis, cytosolic survival, and virulence.

Infect Immun 2021 Feb 22. Epub 2021 Feb 22.

Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison WI

is a Gram-positive, intracellular pathogen that is highly adapted to invade and replicate in the cytosol of eukaryotic cells. Intermediate metabolites in the menaquinone biosynthesis pathway are essential for the cytosolic survival and virulence of , independent of the production of MK and aerobic respiration. Determining which specific intermediate metabolite(s) are essential for cytosolic survival and virulence has been hindered by the lack of an identified DHNA-CoA thioesterase essential for converting DHNA-CoA to DHNA in the MK synthesis pathway. Read More

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February 2021

A stable antimicrobial peptide with dual functions of treating and preventing citrus Huanglongbing.

Proc Natl Acad Sci U S A 2021 Feb;118(6)

Department of Microbiology and Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521;

Citrus Huanglongbing (HLB), caused by a vector-transmitted phloem-limited bacterium Liberibacter asiaticus (Las), is the most devastating citrus disease worldwide. Currently, there are no effective strategies to prevent infection or to cure HLB-positive trees. Here, using comparative analysis between HLB-sensitive citrus cultivars and HLB-tolerant citrus hybrids and relatives, we identified a novel class of stable antimicrobial peptides (SAMPs). Read More

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February 2021

Autophagy restricts mitochondrial DNA damage-induced release of ENDOG (endonuclease G) to regulate genome stability.

Autophagy 2021 Jan 19:1-17. Epub 2021 Jan 19.

Institute of Molecular Medicine, College of Medicine, National Taiwan University , Taipei, Taiwan.

Genotoxic insult causes nuclear and mitochondrial DNA damages with macroautophagy/autophagy induction. The role of mitochondrial DNA (mtDNA) damage in the requirement of autophagy for nuclear DNA (nDNA) stability is unclear. Using site-specific DNA damage approaches, we show that specific nDNA damage alone does not require autophagy for repair unless in the presence of mtDNA damage. Read More

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January 2021

Endoplasmic reticulum membrane receptors of the GET pathway are conserved throughout eukaryotes.

Proc Natl Acad Sci U S A 2021 Jan 21;118(1). Epub 2020 Dec 21.

Developmental Genetics, Centre for Plant Molecular Biology, University of Tübingen, 72076 Tübingen, Germany;

Type II tail-anchored (TA) membrane proteins are involved in diverse cellular processes, including protein translocation, vesicle trafficking, and apoptosis. They are characterized by a single C-terminal transmembrane domain that mediates posttranslational targeting and insertion into the endoplasmic reticulum (ER) via the Guided-Entry of TA proteins (GET) pathway. The GET system was originally described in mammals and yeast but was recently shown to be partially conserved in other eukaryotes, such as higher plants. Read More

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January 2021

Cooperative function of synaptophysin and synapsin in the generation of synaptic vesicle-like clusters in non-neuronal cells.

Nat Commun 2021 01 11;12(1):263. Epub 2021 Jan 11.

Department of Physiology and Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, South Korea.

Clusters of tightly packed synaptic vesicles (SVs) are a defining feature of nerve terminals. While SVs are mobile within the clusters, the clusters have no boundaries consistent with a liquid phase. We previously found that purified synapsin, a peripheral SV protein, can assemble into liquid condensates and trap liposomes into them. Read More

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January 2021

Bringing the Ca sensitivity of myristoylated recoverin into the physiological range.

Open Biol 2021 Jan 6;11(1):200346. Epub 2021 Jan 6.

Department of Neurosciences, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, 37134 Verona, Italy.

The prototypical Ca-sensor protein recoverin (Rec) is thought to regulate the activity of rhodopsin kinase (GRK1) in photoreceptors by switching from a relaxed (R) disc membrane-bound conformation in the dark to a more compact, cytosol-diffusing tense (T) conformation upon cell illumination. However, the apparent affinity for Ca of its physiologically relevant form (myristoylated recoverin) is almost two orders of magnitude too low to support this mechanism . In this work, we compared the individual and synergistic roles of the myristic moiety, the GRK1 target and the disc membrane in modulating the calcium sensitivity of Rec. Read More

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January 2021

The ten amino acids of the oxygen-evolving enhancer of tobacco is sufficient as the peptide residues for protein transport to the chloroplast thylakoid.

Plant Mol Biol 2021 Mar 3;105(4-5):513-523. Epub 2021 Jan 3.

School of Biological Science and Technology, Chonnam National University, Gwangju, 61186, South Korea.

Key Message: The thylakoid transit peptide of tobacco oxygen-evolving enhancer protein contains a minimal ten amino acid sequences for thylakoid lumen transports. This ten amino acids do not contain twin-arginine, which is required for typical chloroplast lumen translocation. Chloroplasts are intracellular organelles responsible for photosynthesis to produce organic carbon for all organisms. Read More

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Lipopolysaccharide Recognition in the Crossroads of TLR4 and Caspase-4/11 Mediated Inflammatory Pathways.

Front Immunol 2020 27;11:585146. Epub 2020 Nov 27.

Research Group Innate Immunity, Research Center Borstel-Leibniz Lung Center, Airway Research Center North (ARCN), German Center for Lung Disease (DZL), Borstel, Germany.

The innate immune response to lipopolysaccharide is essential for host defense against Gram-negative bacteria. In response to bacterial infection, the TLR4/MD-2 complex that is expressed on the surface of macrophages, monocytes, dendritic, and epithelial cells senses picomolar concentrations of endotoxic LPS and triggers the production of various pro-inflammatory mediators. In addition, LPS from extracellular bacteria which is either endocytosed or transfected into the cytosol of host cells or cytosolic LPS produced by intracellular bacteria is recognized by cytosolic proteases caspase-4/11 and hosts guanylate binding proteins that are involved in the assembly and activation of the NLRP3 inflammasome. Read More

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November 2020

Autophosphorylation-induced self-assembly and STIL-dependent reinforcement underlie Plk4's ring-to-dot localization conversion around a human centriole.

Cell Cycle 2020 Dec 15;19(24):3419-3436. Epub 2020 Dec 15.

Laboratory of Metabolism, National Cancer Institute, National Institutes of Health , Bethesda, MD, USA.

Polo-like kinase 4 (Plk4) is a key regulator of centriole biogenesis. Studies have shown that Plk4 undergoes dynamic relocalization from a ring-like pattern around a centriole to a dot-like morphology at the procentriole assembly site and this event is central for inducing centriole biogenesis. However, the detailed mechanisms underlying Plk4's capacity to drive its symmetry-breaking ring-to-dot relocalization remain largely unknown. Read More

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December 2020

Efficient Expression of Soluble Recombinant Protein Fused with Core-Streptavidin in Bacterial Strain with T7 Expression System.

Methods Protoc 2020 Dec 1;3(4). Epub 2020 Dec 1.

Department of Chemical and Biological Engineering, University of Idaho, 875 Perimeter Dr, Moscow, ID 83844, USA.

The limited amount of fusion protein transported into cytosol milieu has made it challenging to obtain a sufficient amount for further applications. To avoid the laborious and expensive task, T7 promoter-driving pET-30a(+) coding for chimeric gene of thymidine phosphorylase and core streptavidin as a model system was constructed and transformed into a variety of strains with T7 expression system. Our results demonstrated that the pET-30a(+)-TP-coreSA/Lemo21(DE3) system is able to provide efficient expression of soluble TP-coreSA fusion protein for purification. Read More

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December 2020

Heterotrimeric G Protein Subunit Gαq Is a Master Switch for Gβγ-Mediated Calcium Mobilization by Gi-Coupled GPCRs.

Mol Cell 2020 12 16;80(6):940-954.e6. Epub 2020 Nov 16.

Molecular, Cellular and Pharmacobiology Section, Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany. Electronic address:

Mechanisms that control mobilization of cytosolic calcium [Ca] are key for regulation of numerous eukaryotic cell functions. One such paradigmatic mechanism involves activation of phospholipase Cβ (PLCβ) enzymes by G protein βγ subunits from activated Gα-Gβγ heterotrimers. Here, we report identification of a master switch to enable this control for PLCβ enzymes in living cells. Read More

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December 2020

cAMP-Independent Activation of the Unfolded Protein Response by Cholera Toxin.

Infect Immun 2021 Jan 19;89(2). Epub 2021 Jan 19.

Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA

Cholera toxin (CT) is an AB protein toxin that activates the stimulatory alpha subunit of the heterotrimeric G protein (Gsα) through ADP-ribosylation. Activation of Gsα produces a cytopathic effect by stimulating adenylate cyclase and the production of cAMP. To reach its cytosolic Gsα target, CT binds to the plasma membrane of a host cell and travels by vesicle carriers to the endoplasmic reticulum (ER). Read More

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January 2021

Riding the tiger - physiological and pathological effects of superoxide and hydrogen peroxide generated in the mitochondrial matrix.

Martin D Brand

Crit Rev Biochem Mol Biol 2020 Dec 4;55(6):592-661. Epub 2020 Nov 4.

Buck Institute for Research on Aging, Novato, CA, USA.

Elevated mitochondrial matrix superoxide and/or hydrogen peroxide concentrations drive a wide range of physiological responses and pathologies. Concentrations of superoxide and hydrogen peroxide in the mitochondrial matrix are set mainly by rates of production, the activities of superoxide dismutase-2 (SOD2) and peroxiredoxin-3 (PRDX3), and by diffusion of hydrogen peroxide to the cytosol. These considerations can be used to generate criteria for assessing whether changes in matrix superoxide or hydrogen peroxide are both necessary and sufficient to drive redox signaling and pathology: is a phenotype affected by suppressing superoxide and hydrogen peroxide production; by manipulating the levels of SOD2, PRDX3 or mitochondria-targeted catalase; and by adding mitochondria-targeted SOD/catalase mimetics or mitochondria-targeted antioxidants? Is the pathology associated with variants in SOD2 and PRDX3 genes? Filtering the large literature on mitochondrial redox signaling using these criteria highlights considerable evidence that mitochondrial superoxide and hydrogen peroxide drive physiological responses involved in cellular stress management, including apoptosis, autophagy, propagation of endoplasmic reticulum stress, cellular senescence, HIF1α signaling, and immune responses. Read More

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December 2020

The selectivity filter of the mitochondrial protein import machinery.

BMC Biol 2020 10 29;18(1):156. Epub 2020 Oct 29.

Institute for Biochemistry and Pathobiochemistry, Ruhr-University Bochum, 44780, Bochum, Germany.

Background: The uptake of newly synthesized nuclear-encoded mitochondrial proteins from the cytosol is mediated by a complex of mitochondrial outer membrane proteins comprising a central pore-forming component and associated receptor proteins. Distinct fractions of proteins initially bind to the receptor proteins and are subsequently transferred to the pore-forming component for import. The aim of this study was the identification of the decisive elements of this machinery that determine the specific selection of the proteins that should be imported. Read More

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October 2020

Mitochondrial pyruvate carriers are required for myocardial stress adaptation.

Nat Metab 2020 11 26;2(11):1248-1264. Epub 2020 Oct 26.

Fraternal Order of Eagles Diabetes Research Center, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.

In addition to fatty acids, glucose and lactate are important myocardial substrates under physiologic and stress conditions. They are metabolized to pyruvate, which enters mitochondria via the mitochondrial pyruvate carrier (MPC) for citric acid cycle metabolism. In the present study, we show that MPC-mediated mitochondrial pyruvate utilization is essential for the partitioning of glucose-derived cytosolic metabolic intermediates, which modulate myocardial stress adaptation. Read More

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November 2020

UBE2T-regulated H2AX monoubiquitination induces hepatocellular carcinoma radioresistance by facilitating CHK1 activation.

J Exp Clin Cancer Res 2020 Oct 21;39(1):222. Epub 2020 Oct 21.

Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.

Background: Radioresistance is the major obstacle in radiation therapy (RT) for hepatocellular carcinoma (HCC). Dysregulation of DNA damage response (DDR), which includes DNA repair and cell cycle checkpoints activation, leads to radioresistance and limits radiotherapy efficacy in HCC patients. However, the underlying mechanism have not been clearly understood. Read More

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October 2020

Three-dimensional reconstruction and comparison of vacuolar membranes in response to viral infection.

J Integr Plant Biol 2021 Feb;63(2):353-364

State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.

The vacuole is a unique plant organelle that plays an important role in maintaining cellular homeostasis under various environmental stress conditions. However, the effects of biotic stress on vacuole structure has not been examined using three-dimensional (3D) visualization. Here, we performed 3D electron tomography to compare the ultrastructural changes in the vacuole during infection with different viruses. Read More

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February 2021

Regulation of NRF1, a master transcription factor of proteasome genes: implications for cancer and neurodegeneration.

Mol Biol Cell 2020 09;31(20):2158-2163

Department of Pathology, Virginia Commonwealth University, Richmond, VA 23298.

The ability to sense proteasome insufficiency and respond by directing the transcriptional synthesis of de novo proteasomes is a trait that is conserved in evolution and is found in organisms ranging from yeast to humans. This homeostatic mechanism in mammalian cells is driven by the transcription factor NRF1. Interestingly, NRF1 is synthesized as an endoplasmic reticulum (ER) membrane protein and when cellular proteasome activity is sufficient, it is retrotranslocated into the cytosol and targeted for destruction by the ER--associated degradation pathway (ERAD). Read More

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September 2020

SAM50, a side door to the mitochondria: The case of cytotoxic proteases.

Pharmacol Res 2020 10 9;160:105196. Epub 2020 Sep 9.

Department of Biomedical Sciences University of Padova, via U. Bassi 58/b, 35129, Padova, PD, Italy; Veneto Institute of Molecular Medicine, Via G. Orus 2, 35129 Padova, PD, Italy. Electronic address:

SAM50, a 7-8 nm diameter β-barrel channel of the mitochondrial outer membrane, is the central channel of the sorting and assembly machinery (SAM) complex involved in the biogenesis of β-barrel proteins. Interestingly, SAM50 is not known to have channel translocase activity; however, we have recently found that this channel is necessary and sufficient for mitochondrial entry of cytotoxic proteases. Cytotoxic lymphocytes eliminate cells that pose potential hazards, such as virus- and bacteria-infected cells as well as cancer cells. Read More

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October 2020

A Membrane-Bound Diacylglycerol Species Induces PKCϵ-Mediated Hepatic Insulin Resistance.

Cell Metab 2020 Oct 2;32(4):654-664.e5. Epub 2020 Sep 2.

Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA. Electronic address:

Nonalcoholic fatty liver disease is strongly associated with hepatic insulin resistance (HIR); however, the key lipid species and molecular mechanisms linking these conditions are widely debated. We developed a subcellular fractionation method to quantify diacylglycerol (DAG) stereoisomers and ceramides in the endoplasmic reticulum (ER), mitochondria, plasma membrane (PM), lipid droplets, and cytosol. Acute knockdown (KD) of diacylglycerol acyltransferase-2 in liver induced HIR in rats. Read More

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October 2020

ROS Regulate Caspase-Dependent Cell Delamination without Apoptosis in the Drosophila Pupal Notum.

iScience 2020 Aug 25;23(8):101413. Epub 2020 Jul 25.

Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan. Electronic address:

Thorax fusion occurs in the midline of the Drosophila pupal notum and involves epithelial cell delamination requiring apoptotic signaling. By genetic screening, we found that NADPH oxidases (Nox and Duox) associated with superoxide anion (O˙) are responsible for caspase-3 activation and delamination. We observed that Nox is upregulated in cells that undergo delamination and that delamination depends on caspase activation. Read More

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The Ca-dependent pathway contributes to changes in the subcellular localization and extracellular release of interleukin-33.

Biochem Biophys Res Commun 2020 10 5;530(4):699-705. Epub 2020 Aug 5.

Laboratory of Molecular Immunobiology, Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama-cho, Ikoma, Nara, 630-0192, Japan; CREST, Japan Science Technology Agency, Japan. Electronic address:

Interleukin-33 (IL-33) is a member of the IL-1 cytokine family and plays critical roles in facilitating type-2 immune responses. IL-33 is localized in the nucleus and released to the extracellular milieu during cell death, although the precise mechanisms underlying IL-33 mobilization remain unclear. Here, we found that nigericin, a toxin derived from Streptomyces hygroscopicus, promoted IL-33 translocation from the nucleus to the cytosol before extracellular release. Read More

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October 2020

The C-terminal region of the oxidoreductase MIA40 stabilizes its cytosolic precursor during mitochondrial import.

BMC Biol 2020 08 6;18(1):96. Epub 2020 Aug 6.

Institute for Biochemistry, Redox Biochemistry, University of Cologne, Zuelpicher Str. 47a, 50674, Cologne, Germany.

Background: The mitochondrial intermembrane space (IMS) is home to proteins fulfilling numerous essential cellular processes, particularly in metabolism and mitochondrial function. All IMS proteins are nuclear encoded and synthesized in the cytosol and must therefore be correctly targeted and transported to the IMS, either through mitochondrial targeting sequences or conserved cysteines and the mitochondrial disulfide relay system. The mitochondrial oxidoreductase MIA40, which catalyzes disulfide formation in the IMS, is imported by the combined action of the protein AIFM1 and MIA40 itself. Read More

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A Cytoplasmic Heme Sensor Illuminates the Impacts of Mitochondrial and Vacuolar Functions and Oxidative Stress on Heme-Iron Homeostasis in Cryptococcus neoformans.

mBio 2020 07 28;11(4). Epub 2020 Jul 28.

Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada

Pathogens must compete with hosts to acquire sufficient iron for proliferation during pathogenesis. The pathogenic fungus is capable of acquiring iron from heme, the most abundant source in vertebrate hosts, although the mechanisms of heme sensing and acquisition are not entirely understood. In this study, we adopted a chromosomally encoded heme sensor developed for to examine cytosolic heme levels in using fluorescence microscopy, fluorimetry, and flow cytometry. Read More

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