scholarly journals Regulation of the CoA Biosynthetic Complex Assembly in Mammalian Cells

2021 ◽  
Vol 22 (3) ◽  
pp. 1131
Author(s):  
Jovana Baković ◽  
David López Martínez ◽  
Savvas Nikolaou ◽  
Bess Yi Kun Yu ◽  
Maria-Armineh Tossounian ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Regulation Of Gene Expression ◽  
A549 Cells ◽  
Metabolic Stress ◽  
Proximity Ligation Assay ◽  
Serum Starvation ◽  
Growth Factor Signaling ◽  
Reye's Syndrome ◽  
Protein Thiols ◽  
Cellular Stresses

Coenzyme A (CoA) is an essential cofactor present in all living cells. Under physiological conditions, CoA mainly functions to generate metabolically active CoA thioesters, which are indispensable for cellular metabolism, the regulation of gene expression, and the biosynthesis of neurotransmitters. When cells are exposed to oxidative or metabolic stress, CoA acts as an important cellular antioxidant that protects protein thiols from overoxidation, and this function is mediated by protein CoAlation. CoA and its derivatives are strictly maintained at levels controlled by nutrients, hormones, metabolites, and cellular stresses. Dysregulation of their biosynthesis and homeostasis has deleterious consequences and has been noted in a range of pathological conditions, including cancer, diabetes, Reye’s syndrome, cardiac hypertrophy, and neurodegeneration. The biochemistry of CoA biosynthesis, which involves five enzymatic steps, has been extensively studied. However, the existence of a CoA biosynthetic complex and the mode of its regulation in mammalian cells are unknown. In this study, we report the assembly of all five enzymes that drive CoA biosynthesis, in HEK293/Pank1β and A549 cells, using the in situ proximity ligation assay. Furthermore, we show that the association of CoA biosynthetic enzymes is strongly upregulated in response to serum starvation and oxidative stress, whereas insulin and growth factor signaling downregulate their assembly.

scholarly journals Coenzyme A, protein CoAlation and redox regulation in mammalian cells

2018 ◽  
Vol 46 (3) ◽  
pp. 721-728 ◽  
Author(s):  
Ivan Gout
Keyword(s):  
Mammalian Cells ◽  
Redox Regulation ◽  
Coenzyme A ◽  
Regulation Of Gene Expression ◽  
Metabolic Stress ◽  
Thiol Group ◽  
Covalent Attachment ◽  
Current Status ◽  
Experimental Conditions ◽  
Diverse Range

In a diverse family of cellular cofactors, coenzyme A (CoA) has a unique design to function in various biochemical processes. The presence of a highly reactive thiol group and a nucleotide moiety offers a diversity of chemical reactions and regulatory interactions. CoA employs them to activate carbonyl-containing molecules and to produce various thioester derivatives (e.g. acetyl CoA, malonyl CoA and 3-hydroxy-3-methylglutaryl CoA), which have well-established roles in cellular metabolism, production of neurotransmitters and the regulation of gene expression. A novel unconventional function of CoA in redox regulation, involving covalent attachment of this coenzyme to cellular proteins in response to oxidative and metabolic stress, has been recently discovered and termed protein CoAlation (S-thiolation by CoA or CoAthiolation). A diverse range of proteins was found to be CoAlated in mammalian cells and tissues under various experimental conditions. Protein CoAlation alters the molecular mass, charge and activity of modified proteins, and prevents them from irreversible sulfhydryl overoxidation. This review highlights the role of a key metabolic integrator CoA in redox regulation in mammalian cells and provides a perspective of the current status and future directions of the emerging field of protein CoAlation.

scholarly journals Protein CoAlation and antioxidant function of coenzyme A in prokaryotic cells

2018 ◽  
Vol 475 (11) ◽  
pp. 1909-1937 ◽  
Author(s):  
Yugo Tsuchiya ◽  
Alexander Zhyvoloup ◽  
Jovana Baković ◽  
Naam Thomas ◽  
Bess Yi Kun Yu ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Redox Regulation ◽  
Coenzyme A ◽  
Regulation Of Gene Expression ◽  
Pantothenic Acid ◽  
Metabolic Stress ◽  
Background Level ◽  
Catalytic Cysteine ◽  
Living Organisms

In all living organisms, coenzyme A (CoA) is an essential cofactor with a unique design allowing it to function as an acyl group carrier and a carbonyl-activating group in diverse biochemical reactions. It is synthesized in a highly conserved process in prokaryotes and eukaryotes that requires pantothenic acid (vitamin B5), cysteine and ATP. CoA and its thioester derivatives are involved in major metabolic pathways, allosteric interactions and the regulation of gene expression. A novel unconventional function of CoA in redox regulation has been recently discovered in mammalian cells and termed protein CoAlation. Here, we report for the first time that protein CoAlation occurs at a background level in exponentially growing bacteria and is strongly induced in response to oxidizing agents and metabolic stress. Over 12% of Staphylococcus aureus gene products were shown to be CoAlated in response to diamide-induced stress. In vitro CoAlation of S. aureus glyceraldehyde-3-phosphate dehydrogenase was found to inhibit its enzymatic activity and to protect the catalytic cysteine 151 from overoxidation by hydrogen peroxide. These findings suggest that in exponentially growing bacteria, CoA functions to generate metabolically active thioesters, while it also has the potential to act as a low-molecular-weight antioxidant in response to oxidative and metabolic stress.

scholarly journals Histone lactylation drives oncogenesis by facilitating m6A reader protein YTHDF2 expression in ocular melanoma

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jie Yu ◽  
Peiwei Chai ◽  
Minyue Xie ◽  
Shengfang Ge ◽  
Jing Ruan ◽  
...  
Keyword(s):  
Macrophage Polarization ◽  
Regulation Of Gene Expression ◽  
Metabolic Stress ◽  
Ocular Melanoma ◽  
Rna Modifications ◽  
M1 Macrophage ◽  
Melanoma Therapy

Abstract Background Histone lactylation, a metabolic stress-related histone modification, plays an important role in the regulation of gene expression during M1 macrophage polarization. However, the role of histone lactylation in tumorigenesis remains unclear. Results Here, we show histone lactylation is elevated in tumors and is associated with poor prognosis of ocular melanoma. Target correction of aberrant histone lactylation triggers therapeutic efficacy both in vitro and in vivo. Mechanistically, histone lactylation contributes to tumorigenesis by facilitating YTHDF2 expression. Moreover, YTHDF2 recognizes the m6A modified PER1 and TP53 mRNAs and promotes their degradation, which accelerates tumorigenesis of ocular melanoma. Conclusion We reveal the oncogenic role of histone lactylation, thereby providing novel therapeutic targets for ocular melanoma therapy. We also bridge histone modifications with RNA modifications, which provides novel understanding of epigenetic regulation in tumorigenesis.

scholarly journals Annexin A2 Mediates Mycoplasma pneumoniae Community-Acquired Respiratory Distress Syndrome Toxin Binding to Eukaryotic Cells

mBio ◽  
2014 ◽  
Vol 5 (4) ◽  
Author(s):  
Sudha R. Somarajan ◽  
Fadi Al-Asadi ◽  
Kumaraguruparan Ramasamy ◽  
Lavanya Pandranki ◽  
Joel B. Baseman ◽  
...  
Keyword(s):  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Mammalian Cells ◽  
Distress Syndrome ◽  
Protein A ◽  
A549 Cells ◽  
Surfactant Protein ◽  
Annexin A2 ◽  
Toxin Binding ◽  
Cards Toxin

ABSTRACT Mycoplasma pneumoniae synthesizes a novel human surfactant protein A (SP-A)-binding cytotoxin, designated community-acquired respiratory distress syndrome (CARDS) toxin, that exhibits ADP-ribosylating and vacuolating activities in mammalian cells and is directly linked to a range of acute and chronic airway diseases, including asthma. In our attempt to detect additional CARDS toxin-binding proteins, we subjected the membrane fraction of human A549 airway cells to affinity chromatography using recombinant CARDS toxin as bait. A 36-kDa A549 cell membrane protein bound to CARDS toxin and was identified by time of flight (TOF) mass spectroscopy as annexin A2 (AnxA2) and verified by immunoblotting with anti-AnxA2 monoclonal antibody. Dose-dependent binding of CARDS toxin to recombinant AnxA2 reinforced the specificity of the interaction, and further studies revealed that the carboxy terminus of CARDS toxin mediated binding to AnxA2. In addition, pretreatment of viable A549 cells with anti-AnxA2 monoclonal antibody or AnxA2 small interfering RNA (siRNA) reduced toxin binding and internalization. Immunofluorescence analysis of CARDS toxin-treated A549 cells demonstrated the colocalization of CARDS toxin with cell surface-associated AnxA2 upon initial binding and with intracellular AnxA2 following toxin internalization. HepG2 cells, which express low levels of AnxA2, were transfected with a plasmid expressing AnxA2 protein, resulting in enhanced binding of CARDS toxin and increased vacuolization. In addition, NCI-H441 cells, which express both AnxA2 and SP-A, upon AnxA2 siRNA transfection, showed decreased binding and subsequent vacuolization. These results indicate that CARDS toxin recognizes AnxA2 as a functional receptor, leading to CARDS toxin-induced changes in mammalian cells. IMPORTANCE Host cell susceptibility to bacterial toxins is usually determined by the presence and abundance of appropriate receptors, which provides a molecular basis for toxin target cell specificities. To perform its ADP-ribosylating and vacuolating activities, community-acquired respiratory distress syndrome (CARDS) toxin must bind to host cell surfaces via receptor-mediated events in order to be internalized and trafficked effectively. Earlier, we reported the binding of CARDS toxin to surfactant protein A (SP-A), and here we show how CARDS toxin uses an alternative receptor to execute its pathogenic properties. CARDS toxin binds selectively to annexin A2 (AnxA2), which exists both on the cell surface and intracellularly. Since AnxA2 regulates membrane dynamics at early stages of endocytosis and trafficking, it serves as a distinct receptor for CARDS toxin binding and internalization and enhances CARDS toxin-induced vacuolization in mammalian cells.

scholarly journals AMPKα1 Regulates Lung and Breast Cancer Progression by Regulating TLR4-Mediated TRAF6-BECN1 Signaling Axis

Cancers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3289
Author(s):  
Mi-Jeong Kim ◽  
Yoon Min ◽  
Juhee Son ◽  
Ji Young Kim ◽  
Ji Su Lee ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Progression ◽  
A549 Cells ◽  
Migration And Invasion ◽  
Serum Starvation ◽  
Lung Cancers ◽  
Cancer Migration ◽  
Expression Of Genes ◽  
Autophagy Induction ◽  
Signaling Axis

TRAF6-BECN1 signaling axis is critical for autophagy induction and functionally implicated in cancer progression. Here, we report that AMP-activated protein kinase alpha 1 (AMPKα1, PRKAA1) is positively involved in autophagy induction and cancer progression by regulating TRAF6-BECN1 signaling axis. Mechanistically, AMPKα1 interacted with TRAF6 and BECN1. It also enhanced ubiquitination of BECN1 and autophagy induction. AMPKα1-knockout (AMPKα1KO) HEK293T or AMPKα1-knockdown (AMPKα1KD) THP-1 cells showed impaired autophagy induced by serum starvation or TLR4 (Toll-like receptor 4) stimulation. Additionally, AMPKα1KD THP-1 cells showed decreases of autophagy-related and autophagosome-related genes induced by TLR4. AMPKα1KO A549 cells exhibited attenuation of cancer migration and invasion induced by TLR4. Moreover, primary non-small cell lung cancers (NSCLCs, n = 6) with low AMPKαl levels showed markedly decreased expression of genes related to autophagy, cell migration and adhesion/metastasis, inflammation, and TLRs whereas these genes were significantly upregulated in NSCLCs (n = 5) with high AMPKαl levels. Consistently, attenuation of cancer migration and invasion could be observed in AMPKα1KO MDA-MB-231 and AMPKα1KO MCF-7 human breast cancer cells. These results suggest that AMPKα1 plays a pivotal role in cancer progression by regulating the TRAF6-BECN1 signaling axis for autophagy induction.

scholarly journals Wnt-3a and Dvl Induce Neurite Retraction by Activating Rho-Associated Kinase

2004 ◽  
Vol 24 (10) ◽  
pp. 4487-4501 ◽  
Author(s):  
Shosei Kishida ◽  
Hideki Yamamoto ◽  
Akira Kikuchi
Keyword(s):  
Neurite Outgrowth ◽  
Pc12 Cells ◽  
Mammalian Cells ◽  
Planar Cell Polarity ◽  
Kinase Inhibitor ◽  
Rho Kinase ◽  
Binding Domain ◽  
Serum Starvation ◽  
Neurite Retraction ◽  
Rho Kinase Inhibitor

ABSTRACT Dvl is a key protein that transmits the Wnt signal to the canonical β-catenin pathway and the noncanonical planar cell polarity (PCP) pathway. We studied the roles of Rho-associated kinase (Rho-kinase), which is activated by Dvl in the PCP pathway of mammalian cells. The expression of Dvl-1, Wnt-1, or Wnt-3a activated Rho-kinase in COS cells, and this activation was inhibited by the Rho-binding domain of Rho-kinase. The expression of Dvl-1 in PC12 cells activated Rho and inhibited nerve growth factor (NGF)-induced neurite outgrowth. This inhibition was reversed by a Rho-kinase inhibitor but not by a c-Jun N-terminal kinase inhibitor. Dvl-1 also inhibited serum starvation-dependent neurite outgrowth of N1E-115 cells, and expression of the Rho-binding domain of Rho-kinase reversed this inhibitory activity of Dvl-1. Dvl-1 mutants that did not activate Rho-kinase did not inhibit the neurite outgrowth of N1E-115 cells. Furthermore, the purified Wnt-3a protein activated Rho-kinase and inhibited the NGF-dependent neurite outgrowth of PC12 cells. Wnt-3a-dependent neurite retraction was also prevented by a Rho-kinase inhibitor and a Dvl-1 mutant that suppresses Wnt-3a-dependent activation of Rho-kinase. These results suggest that Wnt-3a and Dvl regulate neurite formation through Rho-kinase and that PC12 and N1E-115 cells are useful for analyzing the PCP pathway.

Coenzyme A biosynthetic machinery in mammalian cells

2014 ◽  
Vol 42 (4) ◽  
pp. 1112-1117 ◽  
Author(s):  
David Lopez Martinez ◽  
Yugo Tsuchiya ◽  
Ivan Gout
Keyword(s):  
Mammalian Cells ◽  
Coenzyme A ◽  
Regulation Of Gene Expression ◽  
Pantothenic Acid ◽  
Regulatory Interactions ◽  
Malonyl Coa ◽  
Extracellular Stimuli ◽  
Living Organisms ◽  
Enzyme Complexes ◽  
Biosynthetic Machinery

CoA (coenzyme A) is an essential cofactor in all living organisms. CoA and its thioester derivatives [acetyl-CoA, malonyl-CoA, HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) etc.] participate in diverse anabolic and catabolic pathways, allosteric regulatory interactions and the regulation of gene expression. The biosynthesis of CoA requires pantothenic acid, cysteine and ATP, and involves five enzymatic steps that are highly conserved from prokaryotes to eukaryotes. The intracellular levels of CoA and its derivatives change in response to extracellular stimuli, stresses and metabolites, and in human pathologies, such as cancer, metabolic disorders and neurodegeneration. In the present mini-review, we describe the current understanding of the CoA biosynthetic pathway, provide a detailed overview on expression and subcellular localization of enzymes implicated in CoA biosynthesis, their regulation and the potential to form multi-enzyme complexes for efficient and highly co-ordinated biosynthetic process.

scholarly journals In Vivo HP1 Targeting Causes Large-Scale Chromatin Condensation and Enhanced Histone Lysine Methylation

2005 ◽  
Vol 25 (11) ◽  
pp. 4552-4564 ◽  
Author(s):  
Pernette J. Verschure ◽  
Ineke van der Kraan ◽  
Wim de Leeuw ◽  
Johan van der Vlag ◽  
Anne E. Carpenter ◽  
...  
Keyword(s):  
Chromatin Structure ◽  
Mammalian Cells ◽  
Large Scale ◽  
Chromosome Region ◽  
Chromatin Condensation ◽  
Regulation Of Gene Expression ◽  
Lac Repressor ◽  
Homologous Proteins ◽  
Lac Operator

ABSTRACT Changes in chromatin structure are a key aspect in the epigenetic regulation of gene expression. We have used a lac operator array system to visualize by light microscopy the effect of heterochromatin protein 1 (HP1) α (HP1α) and HP1β on large-scale chromatin structure in living mammalian cells. The structure of HP1, containing a chromodomain, a chromoshadow domain, and a hinge domain, allows it to bind to a variety of proteins. In vivo targeting of an enhanced green fluorescent protein-tagged HP1-lac repressor fusion to a lac operator-containing, gene-amplified chromosome region causes local condensation of the higher-order chromatin structure, recruitment of the histone methyltransferase SETDB1, and enhanced trimethylation of histone H3 lysine 9. Polycomb group proteins of both the HPC/HPH and the EED/EZH2 complexes, which are involved in the heritable repression of gene activity, are not recruited to the amplified chromosome region by HP1α and HP1β in vivo targeting. HP1α targeting causes the recruitment of endogenous HP1β to the chromatin region and vice versa, indicating a direct interaction between the two HP1 homologous proteins. Our findings indicate that HP1α and HP1β targeting is sufficient to induce heterochromatin formation.

scholarly journals A more efficient RNAi inducible system for tight regulation of gene expression in mammalian cells and xenograft animals

RNA ◽  
2007 ◽  
Vol 13 (8) ◽  
pp. 1375-1383 ◽  
Author(s):  
J. Zhang ◽  
C. Wang ◽  
N. Ke ◽  
J. Bliesath ◽  
J. Chionis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Mammalian Cells ◽  
Regulation Of Gene Expression ◽  
Expression In Mammalian Cells
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