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Marie-lise Lacombe - One of the best experts on this subject based on the ideXlab platform.
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the mitochondrially localized Nucleoside Diphosphate kinase d nme4 is a novel metastasis suppressor
BMC Biology, 2021Co-Authors: Marie-lise Lacombe, Frederic Lamarche, Olivier De Wever, Teresita Padillabenavides, Alyssa Carlson, Imran Khan, Anda Huna, Sophie Vacher, Claire Calmel, Celine DesbourdesAbstract:Background Mitochondrial Nucleoside Diphosphate kinase (NDPK-D, NME4, NM23-H4) is a multifunctional enzyme mainly localized in the intermembrane space, bound to the inner membrane. Results We constructed loss-of-function mutants of NDPK-D, lacking either NDP kinase activity or membrane interaction and expressed mutants or wild-type protein in cancer cells. In a complementary approach, we performed depletion of NDPK-D by RNA interference. Both loss-of-function mutations and NDPK-D depletion promoted epithelial-mesenchymal transition and increased migratory and invasive potential. Immunocompromised mice developed more metastases when injected with cells expressing mutant NDPK-D as compared to wild-type. This metastatic reprogramming is a consequence of mitochondrial alterations, including fragmentation and loss of mitochondria, a metabolic switch from respiration to glycolysis, increased ROS generation, and further metabolic changes in mitochondria, all of which can trigger pro-metastatic protein expression and signaling cascades. In human cancer, NME4 expression is negatively associated with markers of epithelial-mesenchymal transition and tumor aggressiveness and a good prognosis factor for beneficial clinical outcome. Conclusions These data demonstrate NME4 as a novel metastasis suppressor gene, the first localizing to mitochondria, pointing to a role of mitochondria in metastatic dissemination.
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The mitochondrial Nucleoside Diphosphate kinase (NDPK-D/NME4), a moonlighting protein for cell homeostasis.
Laboratory investigation; a journal of technical methods and pathology, 2018Co-Authors: Marie-lise Lacombe, Malgorzata Tokarska-schlattner, Mathieu Boissan, Uwe SchlattnerAbstract:Mitochondrial Nucleoside Diphosphate kinase (NDPK-D; synonyms: NME4, NM23-H4) represents the major mitochondrial NDP kinase. The homohexameric complex emerged as a protein with multiple functions in bioenergetics and phospholipid signaling. It occurs at different but precise mitochondrial locations and can affect among other mitochondrial shapes and dynamics, as well as the specific elimination of defective mitochondria or cells via mitophagy or apoptosis. With these various functions in cell homeostasis, NDPK-D/NME4 adds to the group of so-called moonlighting (or gene sharing) proteins.
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nme4 Nucleoside Diphosphate kinase d in cardiolipin signaling and mitophagy
Laboratory Investigation, 2018Co-Authors: Uwe Schlattner, Marie-lise Lacombe, Mathieu Boissan, Malgorzata Tokarskaschlattner, Richard M Epand, Valerian E KaganAbstract:Mitophagy is an emerging paradigm for mitochondrial quality control and cell homeostasis. Dysregulation of mitophagy can lead to human pathologies such as neurodegenerative disorders and contributes to the aging process. Complex protein signaling cascades have been described that regulate mitophagy. We have identified a novel lipid signaling pathway that involves the phospholipid cardiolipin (CL). CL is synthesized and normally confined at the inner mitochondrial membrane. However, upon a mitophagic trigger, ie, collapse of the inner membrane potential, CL is rapidly externalized to the mitochondrial surface with the assistance of the hexameric Nucleoside Diphosphate kinase D (NME4, NDPK-D, or NM23-H4). In addition to its NDP kinase activity, NME4/NDPK-D shows intermembrane phospholipid transfer activity in vitro and in cellular systems, which relies on NME4/NDPK-D interaction with CL, CL-dependent crosslinking of inner and outer mitochondrial membranes by symmetrical, hexameric NME4/NDPK-D, and a putative NME4/NDPK-D-based CL-transfer pathway. CL exposed at the mitochondrial surface then serves as an 'eat me' signal for the mitophagic machinery; it is recognized by the LC3 receptor of autophagosomes, targeting the dysfunctional mitochondrion to lysosomal degradation. Similar NME4-supported CL externalization is likely also involved in apoptosis and inflammatory reactions.
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Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity
FASEB Journal, 2017Co-Authors: Evelyne Peuchant, Marie-lise Lacombe, Mathieu Boissan, Jérome Guitton, Marielise Bats, Isabelle Moranvillier, Michel Lepoivre, Dominique Wendum, François Moreau-gaudry, Sandrine DabernatAbstract:NME1 (nonmetastatic expressed 1) gene, which encodes Nucleoside Diphosphate kinase (NDPK) A [also known as nonmetastatic clone 23 (NM23)-H1 in humans and NM23-M1 in mice], is a suppressor of metastasis, but several lines of evidence-mostly from plants-also implicate it in the regulation of the oxidative stress response. Here, our aim was to investigate the physiologic relevance of NDPK A with respect to the oxidative stress response in mammals and to study its molecular basis. NME1-knockout mice died sooner, suffered greater hepatocyte injury, and had lower superoxide dismutase activity than did wild-type (WT) mice in response to paraquat-induced acute oxidative stress. Deletion of NME1 reduced total NDPK activity and exacerbated activation of the stress-related MAPK, JNK, in the liver in response to paraquat. In a mouse transformed hepatocyte cell line and in primary cultures of normal human keratinocytes, MAPK activation in response to H2O2 and UVB, respectively, was dampened by expression of NM23-M1/NM23-H1, dependent on its NDPK catalytic activity. Furthermore, excess or depletion of NM23-M1/NM23-H1 NDPK activity did not affect the intracellular bulk concentration of Nucleoside di- and triphosphates. NME1-deficient mouse embryo fibroblasts grew poorly in culture, were more sensitive to stress than WT fibroblasts, and did not immortalize, which suggested that they senesce earlier than do WT fibroblasts. Collectively, these results indicate that the NDPK activity of NM23-M1/NM23-H1 protects cells from acute oxidative stress by inhibiting activation of JNK in mammal models.-Peuchant, E., Bats, M.-L., Moranvillier, I., Lepoivre, M., Guitton, J., Wendum, D., Lacombe, M.-L., Moreau-Gaudry, F., Boissan, M., Dabernat, S. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity.
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the human nm23 Nucleoside Diphosphate kinases
Journal of Bioenergetics and Biomembranes, 2000Co-Authors: Marie-lise Lacombe, Laurence Milon, Annie Munier, J G Mehus, D O LambethAbstract:Biochemical experiments over the past 40 years have shown that Nucleoside Diphosphate(NDP) kinase activity, which catalyzes phosphoryl transfer from a Nucleoside triphosphate toa Nucleoside Diphosphate, is ubiquitously found in organisms from bacteria to human. Overthe past 10 years, eight human genes of the nm23/NDP kinase family have been discoveredthat can be separated into two groups based on analysis of their sequences. In addition tocatalysis, which may not be exhibited by all isoforms, evidence for regulatory roles has comerecently from the discovery of the genes nm23 and awd, which encode NDP kinases and areinvolved in tumor metastasis and Drosophila development, respectively. Current work showsthat the human NDP kinase genes are differentially expressed in tissues and that their productsare targeted to different subcellular locations. This suggests that Nm23/NDP kinases possessdifferent, but specific, functions within the cell, depending on their localization. The roles ofNDP kinases in metabolic pathways and nucleic acid synthesis are discussed.
Ioan Lascu - One of the best experts on this subject based on the ideXlab platform.
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Nucleoside Diphosphate kinases fuel dynamin superfamily proteins with GTP for membrane remodeling
Science, 2014Co-Authors: Mathieu Boissan, Ioan Lascu, Guillaume Montagnac, Qinfang Shen, Lorena Griparic, Jérome Guitton, Maryse Romao, Nathalie Sauvonnet, Thibault Lagache, Graça RaposoAbstract:Dynamin superfamily molecular motors use guanosine triphosphate (GTP) as a source of energy for membrane-remodeling events. We found that knockdown of Nucleoside Diphosphate kinases (NDPKs) NM23-H1/H2, which produce GTP through adenosine triphosphate (ATP)-driven conversion of guanosine Diphosphate (GDP), inhibited dynamin-mediated endocytosis. NM23-H1/H2 localized at clathrin-coated pits and interacted with the proline-rich domain of dynamin. In vitro, NM23-H1/H2 were recruited to dynamin-induced tubules, stimulated GTP-loading on dynamin, and triggered fission in the presence of ATP and GDP. NM23-H4, a mitochondria-specific NDPK, colocalized with mitochondrial dynamin-like OPA1 involved in mitochondria inner membrane fusion and increased GTP-loading on OPA1. Like OPA1 loss of function, silencing of NM23-H4 but not NM23-H1/H2 resulted in mitochondrial fragmentation, reflecting fusion defects. Thus, NDPKs interact with and provide GTP to dynamins, allowing these motor proteins to work with high thermodynamic efficiency.
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Intersubunit Ionic Interactions Stabilize the Nucleoside Diphosphate Kinase of Mycobacterium tuberculosis.
PLoS ONE, 2013Co-Authors: Florian Georgescauld, Lucile Moynié, Johann Habersetzer, Alain Dautant, Laura Cervoni, Iulia Mocan, Tudor Borza, Pernile Harris, Ioan LascuAbstract:Most Nucleoside Diphosphate kinases (NDPKs) are hexamers. The C-terminal tail interacting with the neighboring subunits is crucial for hexamer stability. In the NDPK from Mycobacterium tuberculosis (Mt) this tail is missing. The quaternary structure of Mt-NDPK is essential for full enzymatic activity and for protein stability to thermal and chemical denaturation. We identified the intersubunit salt bridge Arg(80)-Asp(93) as essential for hexamer stability, compensating for the decreased intersubunit contact area. Breaking the salt bridge by the mutation D93N dramatically decreased protein thermal stability. The mutation also decreased stability to denaturation by urea and guanidinium. The D93N mutant was still hexameric and retained full activity. When exposed to low concentrations of urea it dissociated into folded monomers followed by unfolding while dissociation and unfolding of the wild type simultaneously occur at higher urea concentrations. The dissociation step was not observed in guanidine hydrochloride, suggesting that low concentration of salt may stabilize the hexamer. Indeed, guanidinium and many other salts stabilized the hexamer with a half maximum effect of about 0.1 M, increasing protein thermostability. The crystal structure of the D93N mutant has been solved.
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The catalytic mechanism of Nucleoside Diphosphate kinases.
Journal of bioenergetics and biomembranes, 2000Co-Authors: Ioan Lascu, Philippe GoninAbstract:Nucleoside Diphosphate kinases catalyze the reversible transfer of the γ phosphate of Nucleosidetriphosphates to Nucleoside Diphosphates. This minireview presents recent advances inunderstanding the reaction mechanism using steady-state and fast kinetic studies, X-raycrystallography, and site-directed mutagenesis. We also briefly discuss the physiological relevance ofin vitro studies.
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A point mutation of human Nucleoside Diphosphate kinase A found in aggressive neuroblastoma affects protein folding.
The Journal of biological chemistry, 1997Co-Authors: Ioan Lascu, Marie-lise Lacombe, Sabine Schaertl, Chanquing Wang, Claude Sarger, Anna Giartosio, Gilberd Briand, Manfred KonradAbstract:Abstract The point mutation serine 120 to glycine in the human Nucleoside Diphosphate kinase A has been identified in several aggressive neuroblastomas (Chang, C. L., Zhu, X. X., Thoraval, D. H., Ungar, D., Rawwas, J., Hora, N., Strahler, J. R., Hanash, S. M. & Radany, E. (1994) Nature 370, 335–336). We expressed in bacteria and purified wild-type and S120G mutant Nucleoside Diphosphate kinase A. The mutant enzyme had enzymatic and structural properties similar to the wild-type enzyme, whereas its stability to denaturation by heat and urea was markedly reduced. More importantly, upon renaturation of the urea-denatured mutant protein, a folding intermediate accumulated, having the characteristics of a molten globule. It had no tertiary structure, as shown by near UV circular dichroism, whereas the secondary structure was substantially recovered. The hydrophobic probe 8-anilino-1-naphthalene sulfonate bound to the intermediate species with an increase in fluorescence intensity and a blue shift. The hydrodynamic size was between that expected for a folded and an unfolded monomer. Finally, electrophoresis in a transverse urea gradient displayed no renaturation curve, and the protein showed the tendency to aggregate at the lowest urea concentrations. The existence of a molten globule folding intermediates resulting from an altered folding in the mutated protein might be related to the aggressiveness of neuroblastomas.
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cellular phosphorylation of anti hiv Nucleosides role of Nucleoside Diphosphate kinase
Journal of Biological Chemistry, 1996Co-Authors: Julie Bourdais, Joël Janin, Ioan Lascu, Simon Sarfati, Catherine Guerreiro, Ricardo M Biondi, Michel VeronAbstract:Abstract Nucleotide analogs are widely used in antiviral therapy and particularly against AIDS. Delivered to the cell as Nucleosides, they are phosphorylated into their active triphospho derivative form by cellular kinases from the host. The last step in this series of phosphorylations is performed by Nucleoside Diphosphate (NDP) kinase, an enzyme that can use both purine or pyrimidine and oxy- or deoxynucleotides as substrates. Using pure recombinant human NDP kinase type B (product of the gene nm23-H2), we have characterized the kinetic parameters of several nucleotide analogs for this enzyme. Contrary to what is generally assumed, diphospho- and triphospho- derivatives of azidothymidine as well as of dideoxyadenosine and dideoxythymidine are very poor substrates for NDP kinase. The rate of phosphorylation of these analogs varies between 0.05% and 0.5%, as compared to the corresponding natural nucleotide, a result that is not due to the inability of the analogs to bind to the enzyme. Using the data from the high resolution crystal structure of NDP kinase, we provide an interpretation of these results based on the crucial role played by the 3′-OH moiety of the nucleotide in catalysis.
Herman Slegers - One of the best experts on this subject based on the ideXlab platform.
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extracellular Nucleoside Diphosphate kinase nm23 ndpk modulates normal hematopoietic differentiation
Experimental Hematology, 2002Co-Authors: Roel Willems, Herman Slegers, Inez Rodrigus, Adriaan C. Moulijn, Marc Lenjou, Griet Nijs, Zwi N. Berneman, Dirk R. Van BockstaeleAbstract:Abstract Objective We previously demonstrated the presence of Nucleoside Diphosphate kinase NDPK/NM23 in normal human plasma. It also was reported that extracellular NM23 could inhibit differentiation of certain hematopoietic cell lines. We further investigated the extracellular effect of NM23 on hematopoiesis by adding recombinant NM23-H1, NM23-H2, and NM23-H3 proteins to in vitro differentiation assays of normal human hematopoietic progenitors. Materials and Methods To study the effect on the earlier stages of hematopoietic maturation, NM23 was added to serum-free pre–colony-forming unit (pre-CFU) assays starting from immature CD34 ++ CD38 − bone marrow cells. Serum-free CFU assays starting from CD34 + CD38 + bone marrow cells were used as a model for terminal hematopoietic differentiation. Results In pre-CFU assays, none of the NM23 isoforms used significantly changed the expansion of CD34 ++ CD38 − cells, nor did NM23 alter the CD34 ++ CD38 − cell lineage commitment. In contrast, terminal differentiation of CD34 + CD38 + progenitor cells in CFU assays was significantly altered by addition of NM23 protein. More erythroid burst-forming units and fewer macrophage colonies were observed in cultures containing any of the NM23 isoforms examined. Similar effects were observed using the enzymatically inactive H118N mutant of NM23-H1, strongly suggesting that the observed effect is independent of the Nucleoside Diphosphate kinase activity of NM23. Conclusion We demonstrated a modulating effect of extracellular NM23 proteins on the terminal stages of normal hematopoietic differentiation. Therefore, the fairly high concentrations of NM23 constitutively present in plasma could have a physiologic role in supporting erythropoiesis and inhibiting excessive macrophage formation.
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Nucleoside Diphosphate kinase ndpk nm23 and the waltz with multiple partners possible consequences in tumor metastasis
Clinical & Experimental Metastasis, 2002Co-Authors: Dirk Roymans, Roel Willems, D R Van Blockstaele, Herman SlegersAbstract:Tumor metastasis is responsible for a high degree of mortality in cancer patients. One of the genes involved in tumor metastasis is NM23. At present, eight human isoforms, transcribed from different NM23 genes, have been detected. The gene products have been identified as Nucleoside Diphosphate kinases (NDPKs), most of which catalyse the transfer of the γ-phosphate of a (deoxy)Nucleoside triphosphate to a (deoxy)Nucleoside Diphosphate. However, the function of NDPK isoforms involved in tumor metastasis cannot be explained on the basis of their phosphotransferase activity alone. At present, several other properties, like transcriptional regulation and protein kinase activity, have been assigned to these proteins. Moreover, it has also been shown that NDPKs interact with several other proteins, and binding partners of NDPKs are identified at an increasing rate. Accumulating evidence indicates that protein–protein interactions modulate the molecular action of NDPKs. In this review we provide a brief overview of how NDPKs are correlated with cancer, and discuss when and how the activities assigned to NDPKs may affect metastasis, with special emphasis on the role of protein–NDPK interactions in this process.
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decrease in Nucleoside Diphosphate kinase ndpk nm23 expression during hematopoietic maturation
Journal of Biological Chemistry, 1998Co-Authors: Roel Willems, Marc Lenjou, Griet Nijs, Zwi N. Berneman, Dirk R. Van Bockstaele, Filip Lardon, Hanswillem Snoeck, Herman SlegersAbstract:The Nucleoside Diphosphate kinase (NDPK/nm23) isoforms H1 and H2 were localized in hematopoietic tissues. Flow cytometric analysis and enzymatic assays were used to quantify the intracellular and extracellular concentrations of NDPK. Bone marrow CD34(+) progenitors contained the highest intracellular levels of both nm23-H1 and nm23-H2. Lower levels were measured in more mature bone marrow cells, whereas peripheral blood leukocytes had the lowest expression of nm23. These data suggest a function of NDPK in early hematopoiesis and a down-regulation of NDPK upon differentiation. In addition, an up-regulation of nm23 expression was observed in lymphocytes after induction of proliferation with phytohemagglutinin. Multiparameter flow cytometry demonstrated that this up-regulation occurred during the G0/G1-transition. Flow cytometric analysis also revealed a weak surface expression of nm23 on a number of hematopoietic cell lines, which was not detected on normal hematopoietic cells. Our data also demonstrated the presence of NDPK in human plasma, probably due to a limited in vivo lysis of red blood cells.
Evelyne Peuchant - One of the best experts on this subject based on the ideXlab platform.
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metastasis suppressor nm23 limits oxidative stress in mammals by preventing activation of stress activated protein kinases jnks through its Nucleoside Diphosphate kinase activity
The FASEB Journal, 2017Co-Authors: Jérome Guitton, Evelyne Peuchant, Marielise Bats, Isabelle Moranvillier, Michel Lepoivre, Dominique WendumAbstract:NME1 (nonmetastatic expressed 1) gene, which encodes Nucleoside Diphosphate kinase (NDPK) A [also known as nonmetastatic clone 23 (NM23)-H1 in humans and NM23-M1 in mice], is a suppressor of metastasis, but several lines of evidence-mostly from plants-also implicate it in the regulation of the oxidative stress response. Here, our aim was to investigate the physiologic relevance of NDPK A with respect to the oxidative stress response in mammals and to study its molecular basis. NME1-knockout mice died sooner, suffered greater hepatocyte injury, and had lower superoxide dismutase activity than did wild-type (WT) mice in response to paraquat-induced acute oxidative stress. Deletion of NME1 reduced total NDPK activity and exacerbated activation of the stress-related MAPK, JNK, in the liver in response to paraquat. In a mouse transformed hepatocyte cell line and in primary cultures of normal human keratinocytes, MAPK activation in response to H2O2 and UVB, respectively, was dampened by expression of NM23-M1/NM23-H1, dependent on its NDPK catalytic activity. Furthermore, excess or depletion of NM23-M1/NM23-H1 NDPK activity did not affect the intracellular bulk concentration of Nucleoside di- and triphosphates. NME1-deficient mouse embryo fibroblasts grew poorly in culture, were more sensitive to stress than WT fibroblasts, and did not immortalize, which suggested that they senesce earlier than do WT fibroblasts. Collectively, these results indicate that the NDPK activity of NM23-M1/NM23-H1 protects cells from acute oxidative stress by inhibiting activation of JNK in mammal models.-Peuchant, E., Bats, M.-L., Moranvillier, I., Lepoivre, M., Guitton, J., Wendum, D., Lacombe, M.-L., Moreau-Gaudry, F., Boissan, M., Dabernat, S. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity.
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Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity
FASEB Journal, 2017Co-Authors: Evelyne Peuchant, Marie-lise Lacombe, Mathieu Boissan, Jérome Guitton, Marielise Bats, Isabelle Moranvillier, Michel Lepoivre, Dominique Wendum, François Moreau-gaudry, Sandrine DabernatAbstract:NME1 (nonmetastatic expressed 1) gene, which encodes Nucleoside Diphosphate kinase (NDPK) A [also known as nonmetastatic clone 23 (NM23)-H1 in humans and NM23-M1 in mice], is a suppressor of metastasis, but several lines of evidence-mostly from plants-also implicate it in the regulation of the oxidative stress response. Here, our aim was to investigate the physiologic relevance of NDPK A with respect to the oxidative stress response in mammals and to study its molecular basis. NME1-knockout mice died sooner, suffered greater hepatocyte injury, and had lower superoxide dismutase activity than did wild-type (WT) mice in response to paraquat-induced acute oxidative stress. Deletion of NME1 reduced total NDPK activity and exacerbated activation of the stress-related MAPK, JNK, in the liver in response to paraquat. In a mouse transformed hepatocyte cell line and in primary cultures of normal human keratinocytes, MAPK activation in response to H2O2 and UVB, respectively, was dampened by expression of NM23-M1/NM23-H1, dependent on its NDPK catalytic activity. Furthermore, excess or depletion of NM23-M1/NM23-H1 NDPK activity did not affect the intracellular bulk concentration of Nucleoside di- and triphosphates. NME1-deficient mouse embryo fibroblasts grew poorly in culture, were more sensitive to stress than WT fibroblasts, and did not immortalize, which suggested that they senesce earlier than do WT fibroblasts. Collectively, these results indicate that the NDPK activity of NM23-M1/NM23-H1 protects cells from acute oxidative stress by inhibiting activation of JNK in mammal models.-Peuchant, E., Bats, M.-L., Moranvillier, I., Lepoivre, M., Guitton, J., Wendum, D., Lacombe, M.-L., Moreau-Gaudry, F., Boissan, M., Dabernat, S. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity.
Mathieu Boissan - One of the best experts on this subject based on the ideXlab platform.
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The mitochondrial Nucleoside Diphosphate kinase (NDPK-D/NME4), a moonlighting protein for cell homeostasis.
Laboratory investigation; a journal of technical methods and pathology, 2018Co-Authors: Marie-lise Lacombe, Malgorzata Tokarska-schlattner, Mathieu Boissan, Uwe SchlattnerAbstract:Mitochondrial Nucleoside Diphosphate kinase (NDPK-D; synonyms: NME4, NM23-H4) represents the major mitochondrial NDP kinase. The homohexameric complex emerged as a protein with multiple functions in bioenergetics and phospholipid signaling. It occurs at different but precise mitochondrial locations and can affect among other mitochondrial shapes and dynamics, as well as the specific elimination of defective mitochondria or cells via mitophagy or apoptosis. With these various functions in cell homeostasis, NDPK-D/NME4 adds to the group of so-called moonlighting (or gene sharing) proteins.
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nme4 Nucleoside Diphosphate kinase d in cardiolipin signaling and mitophagy
Laboratory Investigation, 2018Co-Authors: Uwe Schlattner, Marie-lise Lacombe, Mathieu Boissan, Malgorzata Tokarskaschlattner, Richard M Epand, Valerian E KaganAbstract:Mitophagy is an emerging paradigm for mitochondrial quality control and cell homeostasis. Dysregulation of mitophagy can lead to human pathologies such as neurodegenerative disorders and contributes to the aging process. Complex protein signaling cascades have been described that regulate mitophagy. We have identified a novel lipid signaling pathway that involves the phospholipid cardiolipin (CL). CL is synthesized and normally confined at the inner mitochondrial membrane. However, upon a mitophagic trigger, ie, collapse of the inner membrane potential, CL is rapidly externalized to the mitochondrial surface with the assistance of the hexameric Nucleoside Diphosphate kinase D (NME4, NDPK-D, or NM23-H4). In addition to its NDP kinase activity, NME4/NDPK-D shows intermembrane phospholipid transfer activity in vitro and in cellular systems, which relies on NME4/NDPK-D interaction with CL, CL-dependent crosslinking of inner and outer mitochondrial membranes by symmetrical, hexameric NME4/NDPK-D, and a putative NME4/NDPK-D-based CL-transfer pathway. CL exposed at the mitochondrial surface then serves as an 'eat me' signal for the mitophagic machinery; it is recognized by the LC3 receptor of autophagosomes, targeting the dysfunctional mitochondrion to lysosomal degradation. Similar NME4-supported CL externalization is likely also involved in apoptosis and inflammatory reactions.
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Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity
FASEB Journal, 2017Co-Authors: Evelyne Peuchant, Marie-lise Lacombe, Mathieu Boissan, Jérome Guitton, Marielise Bats, Isabelle Moranvillier, Michel Lepoivre, Dominique Wendum, François Moreau-gaudry, Sandrine DabernatAbstract:NME1 (nonmetastatic expressed 1) gene, which encodes Nucleoside Diphosphate kinase (NDPK) A [also known as nonmetastatic clone 23 (NM23)-H1 in humans and NM23-M1 in mice], is a suppressor of metastasis, but several lines of evidence-mostly from plants-also implicate it in the regulation of the oxidative stress response. Here, our aim was to investigate the physiologic relevance of NDPK A with respect to the oxidative stress response in mammals and to study its molecular basis. NME1-knockout mice died sooner, suffered greater hepatocyte injury, and had lower superoxide dismutase activity than did wild-type (WT) mice in response to paraquat-induced acute oxidative stress. Deletion of NME1 reduced total NDPK activity and exacerbated activation of the stress-related MAPK, JNK, in the liver in response to paraquat. In a mouse transformed hepatocyte cell line and in primary cultures of normal human keratinocytes, MAPK activation in response to H2O2 and UVB, respectively, was dampened by expression of NM23-M1/NM23-H1, dependent on its NDPK catalytic activity. Furthermore, excess or depletion of NM23-M1/NM23-H1 NDPK activity did not affect the intracellular bulk concentration of Nucleoside di- and triphosphates. NME1-deficient mouse embryo fibroblasts grew poorly in culture, were more sensitive to stress than WT fibroblasts, and did not immortalize, which suggested that they senesce earlier than do WT fibroblasts. Collectively, these results indicate that the NDPK activity of NM23-M1/NM23-H1 protects cells from acute oxidative stress by inhibiting activation of JNK in mammal models.-Peuchant, E., Bats, M.-L., Moranvillier, I., Lepoivre, M., Guitton, J., Wendum, D., Lacombe, M.-L., Moreau-Gaudry, F., Boissan, M., Dabernat, S. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its Nucleoside Diphosphate kinase activity.
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Nucleoside Diphosphate kinases fuel dynamin superfamily proteins with GTP for membrane remodeling
Science, 2014Co-Authors: Mathieu Boissan, Ioan Lascu, Guillaume Montagnac, Qinfang Shen, Lorena Griparic, Jérome Guitton, Maryse Romao, Nathalie Sauvonnet, Thibault Lagache, Graça RaposoAbstract:Dynamin superfamily molecular motors use guanosine triphosphate (GTP) as a source of energy for membrane-remodeling events. We found that knockdown of Nucleoside Diphosphate kinases (NDPKs) NM23-H1/H2, which produce GTP through adenosine triphosphate (ATP)-driven conversion of guanosine Diphosphate (GDP), inhibited dynamin-mediated endocytosis. NM23-H1/H2 localized at clathrin-coated pits and interacted with the proline-rich domain of dynamin. In vitro, NM23-H1/H2 were recruited to dynamin-induced tubules, stimulated GTP-loading on dynamin, and triggered fission in the presence of ATP and GDP. NM23-H4, a mitochondria-specific NDPK, colocalized with mitochondrial dynamin-like OPA1 involved in mitochondria inner membrane fusion and increased GTP-loading on OPA1. Like OPA1 loss of function, silencing of NM23-H4 but not NM23-H1/H2 resulted in mitochondrial fragmentation, reflecting fusion defects. Thus, NDPKs interact with and provide GTP to dynamins, allowing these motor proteins to work with high thermodynamic efficiency.
