LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 8 of total 8

Search options

  1. Article ; Online: Ataluren and aminoglycosides stimulate read-through of nonsense codons by orthogonal mechanisms.

    Ng, Martin Y / Li, Hong / Ghelfi, Mikel D / Goldman, Yale E / Cooperman, Barry S

    Proceedings of the National Academy of Sciences of the United States of America

    2021  Volume 118, Issue 2

    Abstract: During protein synthesis, nonsense mutations, resulting in premature stop codons (PSCs), produce truncated, inactive protein products. Such defective gene products give rise to many diseases, including cystic fibrosis, Duchenne muscular dystrophy (DMD), ... ...

    Abstract During protein synthesis, nonsense mutations, resulting in premature stop codons (PSCs), produce truncated, inactive protein products. Such defective gene products give rise to many diseases, including cystic fibrosis, Duchenne muscular dystrophy (DMD), and some cancers. Small molecule nonsense suppressors, known as TRIDs (translational read-through-inducing drugs), stimulate stop codon read-through. The best characterized TRIDs are ataluren, which has been approved by the European Medicines Agency for the treatment of DMD, and G418, a structurally dissimilar aminoglycoside. Previously [1], we applied a highly purified in vitro eukaryotic translation system to demonstrate that both aminoglycosides like G418 and more hydrophobic molecules like ataluren stimulate read-through by direct interaction with the cell's protein synthesis machinery. Our results suggested that they might do so by different mechanisms. Here, we pursue this suggestion through a more-detailed investigation of ataluren and G418 effects on read-through. We find that ataluren stimulation of read-through derives exclusively from its ability to inhibit release factor activity. In contrast, G418 increases functional near-cognate tRNA mispairing with a PSC, resulting from binding to its tight site on the ribosome, with little if any effect on release factor activity. The low toxicity of ataluren suggests that development of new TRIDs exclusively directed toward inhibiting termination should be a priority in combatting PSC diseases. Our results also provide rate measurements of some of the elementary steps during the eukaryotic translation elongation cycle, allowing us to determine how these rates are modified when cognate tRNA is replaced by near-cognate tRNA ± TRIDs.
    MeSH term(s) Aminoglycosides/metabolism ; Aminoglycosides/pharmacology ; Animals ; Artemia/genetics ; Codon, Nonsense/drug effects ; Codon, Nonsense/metabolism ; Codon, Terminator/drug effects ; Codon, Terminator/metabolism ; Cystic Fibrosis/genetics ; Muscular Dystrophy, Duchenne/genetics ; Oxadiazoles/metabolism ; Oxadiazoles/pharmacology ; Peptide Chain Elongation, Translational/drug effects ; Protein Biosynthesis/drug effects ; Protein Synthesis Inhibitors ; RNA, Transfer/drug effects ; RNA, Transfer/genetics ; RNA, Transfer/metabolism ; Ribosomes/drug effects ; Saccharomyces/genetics
    Chemical Substances Aminoglycosides ; Codon, Nonsense ; Codon, Terminator ; Oxadiazoles ; Protein Synthesis Inhibitors ; RNA, Transfer (9014-25-9) ; ataluren (K16AME9I3V)
    Language English
    Publishing date 2021-01-07
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2020599118
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article: Cytosolic and mitochondrial translation elongation are coordinated through the molecular chaperone TRAP1 for the synthesis and import of mitochondrial proteins.

    Avolio, Rosario / Agliarulo, Ilenia / Criscuolo, Daniela / Sarnataro, Daniela / Auriemma, Margherita / Pennacchio, Sara / Calice, Giovanni / Ng, Martin Y / Giorgi, Carlotta / Pinton, Paolo / Cooperman, Barry / Landriscina, Matteo / Esposito, Franca / Matassa, Danilo Swann

    bioRxiv : the preprint server for biology

    2023  

    Abstract: A complex interplay between mRNA translation and cellular respiration has been recently unveiled, but its regulation in humans is poorly characterized in either health or disease. Cancer cells radically reshape both biosynthetic and bioenergetic pathways ...

    Abstract A complex interplay between mRNA translation and cellular respiration has been recently unveiled, but its regulation in humans is poorly characterized in either health or disease. Cancer cells radically reshape both biosynthetic and bioenergetic pathways to sustain their aberrant growth rates. In this regard, we have shown that the molecular chaperone TRAP1 not only regulates the activity of respiratory complexes, behaving alternatively as an oncogene or a tumor suppressor, but also plays a concomitant moonlighting function in mRNA translation regulation. Herein we identify the molecular mechanisms involved, demonstrating that TRAP1: i) binds both mitochondrial and cytosolic ribosomes as well as translation elongation factors, ii) slows down translation elongation rate, and iii) favors localized translation in the proximity of mitochondria. We also provide evidence that TRAP1 is coexpressed in human tissues with the mitochondrial translational machinery, which is responsible for the synthesis of respiratory complex proteins. Altogether, our results show an unprecedented level of complexity in the regulation of cancer cell metabolism, strongly suggesting the existence of a tight feedback loop between protein synthesis and energy metabolism, based on the demonstration that a single molecular chaperone plays a role in both mitochondrial and cytosolic translation, as well as in mitochondrial respiration.
    Language English
    Publishing date 2023-01-19
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.01.19.524708
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Cytosolic and mitochondrial translation elongation are coordinated through the molecular chaperone TRAP1 for the synthesis and import of mitochondrial proteins.

    Avolio, Rosario / Agliarulo, Ilenia / Criscuolo, Daniela / Sarnataro, Daniela / Auriemma, Margherita / De Lella, Sabrina / Pennacchio, Sara / Calice, Giovanni / Ng, Martin Y / Giorgi, Carlotta / Pinton, Paolo / Cooperman, Barry S / Landriscina, Matteo / Esposito, Franca / Matassa, Danilo Swann

    Genome research

    2023  Volume 33, Issue 8, Page(s) 1242–1257

    Abstract: A complex interplay between mRNA translation and cellular respiration has been recently unveiled, but its regulation in humans is poorly characterized in either health or disease. Cancer cells radically reshape both biosynthetic and bioenergetic pathways ...

    Abstract A complex interplay between mRNA translation and cellular respiration has been recently unveiled, but its regulation in humans is poorly characterized in either health or disease. Cancer cells radically reshape both biosynthetic and bioenergetic pathways to sustain their aberrant growth rates. In this regard, we have shown that the molecular chaperone TRAP1 not only regulates the activity of respiratory complexes, behaving alternatively as an oncogene or a tumor suppressor, but also plays a concomitant moonlighting function in mRNA translation regulation. Herein, we identify the molecular mechanisms involved, showing that TRAP1 (1) binds both mitochondrial and cytosolic ribosomes, as well as translation elongation factors; (2) slows down translation elongation rate; and (3) favors localized translation in the proximity of mitochondria. We also provide evidence that TRAP1 is coexpressed in human tissues with the mitochondrial translational machinery, which is responsible for the synthesis of respiratory complex proteins. Altogether, our results show an unprecedented level of complexity in the regulation of cancer cell metabolism, strongly suggesting the existence of a tight feedback loop between protein synthesis and energy metabolism, based on the demonstration that a single molecular chaperone plays a role in both mitochondrial and cytosolic translation, as well as in mitochondrial respiration.
    MeSH term(s) Humans ; HSP90 Heat-Shock Proteins/genetics ; HSP90 Heat-Shock Proteins/metabolism ; Mitochondrial Proteins/genetics ; Mitochondrial Proteins/metabolism ; Molecular Chaperones/genetics ; Molecular Chaperones/metabolism ; Neoplasms/genetics ; Neoplasms/metabolism ; Neoplasms/pathology ; Protein Biosynthesis/genetics ; Protein Biosynthesis/physiology ; Ribosomes/genetics ; Ribosomes/metabolism ; Peptide Chain Elongation, Translational/genetics ; Peptide Chain Elongation, Translational/physiology ; Mitochondria/genetics ; Mitochondria/metabolism
    Chemical Substances HSP90 Heat-Shock Proteins ; Mitochondrial Proteins ; Molecular Chaperones ; TRAP1 protein, human
    Language English
    Publishing date 2023-07-24
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1284872-4
    ISSN 1549-5469 ; 1088-9051 ; 1054-9803
    ISSN (online) 1549-5469
    ISSN 1088-9051 ; 1054-9803
    DOI 10.1101/gr.277755.123
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Kinetics of initiating polypeptide elongation in an IRES-dependent system.

    Zhang, Haibo / Ng, Martin Y / Chen, Yuanwei / Cooperman, Barry S

    eLife

    2016  Volume 5

    Abstract: The intergenic IRES of Cricket Paralysis Virus (CrPV-IRES) forms a tight complex with 80S ribosomes capable of initiating the cell-free synthesis of complete proteins in the absence of initiation factors. Such synthesis raises the question of what effect ...

    Abstract The intergenic IRES of Cricket Paralysis Virus (CrPV-IRES) forms a tight complex with 80S ribosomes capable of initiating the cell-free synthesis of complete proteins in the absence of initiation factors. Such synthesis raises the question of what effect the necessary IRES dissociation from the tRNA binding sites, and ultimately from all of the ribosome, has on the rates of initial peptide elongation steps as nascent peptide is formed. Here we report the first results measuring rates of reaction for the initial cycles of IRES-dependent elongation. Our results demonstrate that 1) the first two cycles of elongation proceed much more slowly than subsequent cycles, 2) these reduced rates arise from slow pseudo-translocation and translocation steps, and 3) the retarding effect of ribosome-bound IRES on protein synthesis is largely overcome following translocation of tripeptidyl-tRNA. Our results also provide a straightforward approach to detailed mechanistic characterization of many aspects of eukaryotic polypeptide elongation.
    MeSH term(s) Animals ; Crustacea/virology ; Dicistroviridae/classification ; Dicistroviridae/genetics ; Dicistroviridae/metabolism ; Kinetics ; Peptide Chain Elongation, Translational ; Peptide Chain Initiation, Translational ; Polyproteins/genetics ; RNA, Transfer/genetics ; RNA, Transfer/metabolism ; RNA, Viral/metabolism ; Ribosomes/metabolism
    Chemical Substances Polyproteins ; RNA, Viral ; RNA, Transfer (9014-25-9)
    Language English
    Publishing date 2016-06-02
    Publishing country England
    Document type Journal Article
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.13429
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: Study of tert-Amyl Methyl Ether Low Temperature Oxidation Using Synchrotron Photoionization Mass Spectrometry.

    Ng, Martin Y / Bryan, Brittany M / Nelson, Jordan / Meloni, Giovanni

    The journal of physical chemistry. A

    2015  Volume 119, Issue 32, Page(s) 8667–8682

    Abstract: This paper examines the oxidation reaction of tert-amyl methyl ether (TAME), an oxygenated fuel additive, with chlorine radical initiators in the presence of oxygen. Data are collected at 298, 550, and 700 K. Reaction intermediates and products are ... ...

    Abstract This paper examines the oxidation reaction of tert-amyl methyl ether (TAME), an oxygenated fuel additive, with chlorine radical initiators in the presence of oxygen. Data are collected at 298, 550, and 700 K. Reaction intermediates and products are probed by a multiplexed chemical kinetics synchrotron photoionization mass spectrometer (SPIMS) and characterized on the basis of the mass-to-charge ratio, ionization energy, and photoionization spectra. Branching fractions of primary products are obtained at the different reaction temperatures. CBS-QB3 computations are also carried out to study the potential energy surface of the investigated reactions to validate detected primary products.
    Language English
    Publishing date 2015-08-13
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/acs.jpca.5b05223
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article ; Online: Synchrotron Photoionization Study of Mesitylene Oxidation Initiated by Reaction with Cl(

    Ng, Martin Y / Nelson, Jordan / Taatjes, Craig A / Osborn, David L / Meloni, Giovanni

    The journal of physical chemistry. A

    2014  Volume 118, Issue 21, Page(s) 3735–3748

    Abstract: This work studies the oxidation of mesitylene (1,3,5-trimethylbenzene) initiated by O( ...

    Abstract This work studies the oxidation of mesitylene (1,3,5-trimethylbenzene) initiated by O(
    Language English
    Publishing date 2014-05-29
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/jp500260f
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article: New

    Ng, Martin Y / Zhang, Haibo / Weil, Amy / Singh, Vijay / Jamiolkowski, Ryan / Baradaran-Heravi, Alireza / Roberge, Michel / Jacobson, Allan / Friesen, Westley / Welch, Ellen / Goldman, Yale E / Cooperman, Barry S

    ACS medicinal chemistry letters

    2018  Volume 9, Issue 12, Page(s) 1285–1291

    Abstract: Nonsense suppressors (NonSups) induce "readthrough", i.e., the selection of near cognate tRNAs at premature termination codons and insertion of the corresponding amino acid into nascent polypeptide. Prior readthrough measurements utilized contexts in ... ...

    Abstract Nonsense suppressors (NonSups) induce "readthrough", i.e., the selection of near cognate tRNAs at premature termination codons and insertion of the corresponding amino acid into nascent polypeptide. Prior readthrough measurements utilized contexts in which NonSups can promote readthrough directly, by binding to one or more of the components of the protein synthesis machinery, or indirectly, by several other mechanisms. Here we utilize a new, highly purified
    Language English
    Publishing date 2018-11-21
    Publishing country United States
    Document type Journal Article
    ISSN 1948-5875
    ISSN 1948-5875
    DOI 10.1021/acsmedchemlett.8b00472
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  8. Article ; Online: Low-temperature combustion chemistry of biofuels: pathways in the initial low-temperature (550 K-750 K) oxidation chemistry of isopentanol.

    Welz, Oliver / Zádor, Judit / Savee, John D / Ng, Martin Y / Meloni, Giovanni / Fernandes, Ravi X / Sheps, Leonid / Simmons, Blake A / Lee, Taek Soon / Osborn, David L / Taatjes, Craig A

    Physical chemistry chemical physics : PCCP

    2012  Volume 14, Issue 9, Page(s) 3112–3127

    Abstract: The branched C(5) alcohol isopentanol (3-methylbutan-1-ol) has shown promise as a potential biofuel both because of new advanced biochemical routes for its production and because of its combustion characteristics, in particular as a fuel for homogeneous- ... ...

    Abstract The branched C(5) alcohol isopentanol (3-methylbutan-1-ol) has shown promise as a potential biofuel both because of new advanced biochemical routes for its production and because of its combustion characteristics, in particular as a fuel for homogeneous-charge compression ignition (HCCI) or related strategies. In the present work, the fundamental autoignition chemistry of isopentanol is investigated by using the technique of pulsed-photolytic Cl-initiated oxidation and by analyzing the reacting mixture by time-resolved tunable synchrotron photoionization mass spectrometry in low-pressure (8 Torr) experiments in the 550-750 K temperature range. The mass-spectrometric experiments reveal a rich chemistry for the initial steps of isopentanol oxidation and give new insight into the low-temperature oxidation mechanism of medium-chain alcohols. Formation of isopentanal (3-methylbutanal) and unsaturated alcohols (including enols) associated with HO(2) production was observed. Cyclic ether channels are not observed, although such channels dominate OH formation in alkane oxidation. Rather, products are observed that correspond to formation of OH viaβ-C-C bond fission pathways of QOOH species derived from β- and γ-hydroxyisopentylperoxy (RO(2)) radicals. In these pathways, internal hydrogen abstraction in the RO(2)⇄ QOOH isomerization reaction takes place from either the -OH group or the C-H bond in α-position to the -OH group. These pathways should be broadly characteristic for longer-chain alcohol oxidation. Isomer-resolved branching ratios are deduced, showing evolution of the main products from 550 to 750 K, which can be qualitatively explained by the dominance of RO(2) chemistry at lower temperature and hydroxyisopentyl decomposition at higher temperature.
    MeSH term(s) Biofuels ; Hydroxyl Radical/chemistry ; Isomerism ; Oxidation-Reduction ; Pentanols/chemistry ; Peroxides/chemistry ; Temperature
    Chemical Substances Biofuels ; Pentanols ; Peroxides ; perhydroxyl radical (3170-83-0) ; Hydroxyl Radical (3352-57-6) ; isopentyl alcohol (DEM9NIT1J4)
    Language English
    Publishing date 2012-03-07
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/c2cp23248k
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top