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Dandurand J, Monné M, Samouillan V, Rosa M, Laurita A, Pistone A, Bisaccia D, Matera I, Bisaccia F, Ostuni A. The 75-99 C-Terminal Peptide of URG7 Protein Promotes α-Synuclein Disaggregation. Int J Mol Sci 2024; 25:1135. [PMID: 38256207 PMCID: PMC10816444 DOI: 10.3390/ijms25021135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 01/13/2024] [Accepted: 01/15/2024] [Indexed: 01/24/2024] Open
Abstract
Up Regulation Gene seven (URG7) is the pseudogene 2 of the transporter ABCC6. The translated URG7 protein is localized with its single transmembrane α-helix in the endoplasmic reticulum (ER) membrane, orienting the N- and C-terminal regions in the lumen and cytoplasm, respectively, and it plays a crucial role in the folding of ER proteins. Previously, the C-terminal region of URG7 (PU, residues 75-99) has been shown to modify the aggregation state of α-synuclein in the lysate of HepG2 cells. PU analogs were synthesized, and their anti-aggregation potential was tested in vitro on α-synuclein obtained using recombinant DNA technology. Circular dichroism (CD), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, and microscopic techniques were used to assess the sample's behavior. The results show that the peptides studied by themselves are prone to clathrate-like structure formation of variable stability. Aggregation of α-synuclein is accompanied by desolvation of its peptide chain and an increase in intermolecular β-sheets. The PU analogs all interact with α-synuclein aggregates and those possessing the most stable clathrate-like structures have the highest disaggregating effect. These findings suggest that the C-terminal region of URG7 may have a role in interacting and modulating α-synuclein structures and could be used to generate interesting therapeutic candidates as disaggregators of α-synuclein.
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Affiliation(s)
- Jany Dandurand
- CIRIMAT Physique des Polymères, Université Toulouse 3, Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse, France; (J.D.); (V.S.)
| | - Magnus Monné
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
| | - Valérie Samouillan
- CIRIMAT Physique des Polymères, Université Toulouse 3, Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse, France; (J.D.); (V.S.)
| | - Martina Rosa
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
| | - Alessandro Laurita
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
| | - Alessandro Pistone
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
| | | | - Ilenia Matera
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
| | - Faustino Bisaccia
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
| | - Angela Ostuni
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy; (M.M.); (M.R.); (A.L.); (A.P.); (I.M.)
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Ostuni A, Iovane V, Monné M, Crudele MA, Scicluna MT, Nardini R, Raimondi P, Frontoso R, Boni R, Bavoso A. A double-strain TM (gp45) polypeptide antigen and its application in the serodiagnosis of equine infectious anemia. J Virol Methods 2023; 315:114704. [PMID: 36842487 DOI: 10.1016/j.jviromet.2023.114704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 02/26/2023]
Abstract
Lentiviruses, including equine infectious anemia virus (EIAV), are considered viral quasispecies because of their intrinsic genetic, structural and phenotypic variability. Immunoenzymatic tests (ELISA) for EIAV reported in the literature were obtained mainly by using the capsid protein p26, which is derived almost exclusively from a single strain (Wyoming), and do not reflect the great potential epitopic variability of the EIAV quasispecies. In this investigation, the GenBank database was exploited in a systematic approach to design a set of representative protein antigens useful for EIAV serodiagnosis. The main bioinformatic tools used were clustering, molecular modelling, epitope predictions and aggregative/ solubility predictions. This approach led to the design of two antigenic proteins, i.e. a full sequence p26 capsid protein and a doublestrain polypeptide derived from the gp45 transmembrane protein fused to Maltose Binding Protein (MBP) that were expressed by recombinant DNA technology starting from synthetic genes, and analyzed by circular dichroism (CD) spectroscopy. Both proteins were used in an indirect ELISA test that can address some of the high variability of EIAV. The novel addition of the gp45 double-strain antigen contributed to enhance the diagnostic sensitivity and could be also useful for immunoblotting application.
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Affiliation(s)
- Angela Ostuni
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100 Potenza, Italy.
| | - Valentina Iovane
- Dipartimento di Agraria - Università degli Studi di Napoli Federico II -Via Università, 100 - 80055 Portici, NA, Italy
| | - Magnus Monné
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100 Potenza, Italy
| | | | - Maria Teresa Scicluna
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova, 1411, 00178 Roma, Italy
| | - Roberto Nardini
- Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Via Appia Nuova, 1411, 00178 Roma, Italy
| | | | - Raffaele Frontoso
- OneHEco APS, 84047 Capaccio Paestum, SA, Italy; Istituto Zooprofilattico Sperimentale del Mezzogiorno Via Salute, 2 - 80055 Portici, Napoli, Italy
| | - Raffaele Boni
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100 Potenza, Italy
| | - Alfonso Bavoso
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100 Potenza, Italy
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Monné M, Cianciulli A, Panaro MA, Calvello R, De Grassi A, Palmieri L, Mitolo V, Palmieri F. New Insights into the Evolution and Gene Structure of the Mitochondrial Carrier Family Unveiled by Analyzing the Frequent and Conserved Intron Positions. Mol Biol Evol 2023; 40:7077214. [PMID: 36916992 PMCID: PMC10027655 DOI: 10.1093/molbev/msad051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/13/2023] [Accepted: 02/27/2023] [Indexed: 03/16/2023] Open
Abstract
Mitochondrial carriers (MCs) belong to a eukaryotic protein family of transporters that in higher organisms is called the solute carrier family 25 (SLC25). All MCs have characteristic triplicated sequence repeats forming a 3-fold symmetrical structure of a six-transmembrane α-helix bundle with a centrally located substrate-binding site. Biochemical characterization has shown that MCs altogether transport a wide variety of substrates but can be divided into subfamilies, each transporting a few specific substrates. We have investigated the intron positions in the human MC genes and their orthologs of highly diversified organisms. The results demonstrate that several intron positions are present in numerous MC sequences at the same specific points, of which some are 3-fold symmetry related. Many of these frequent intron positions are also conserved in subfamilies or in groups of subfamilies transporting similar substrates. The analyses of the frequent and conserved intron positions in MCs suggest phylogenetic relationships not only between close but also distant homologs as well as a possible involvement of the intron positions in the evolution of the substrate specificity diversification of the MC family members.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
- Department of Sciences, University of Basilicata, Potenza, Italy
| | - Antonia Cianciulli
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
| | - Maria A Panaro
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
| | - Rosa Calvello
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
| | - Anna De Grassi
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
| | - Vincenzo Mitolo
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Environment, University of Bari, Bari, Italy
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
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Belaabed S, Khalfaoui A, Parisi V, Santoro V, Russo D, Ponticelli M, Monné M, Rebbas K, Milella L, Donadio G. Rhanteriol, a New Rhanterium suaveolens Desf. Lignan with Pharmacological Potential as an Inhibitor of Enzymes Involved in Neurodegeneration and Type 2 Diabetes. Plants (Basel) 2023; 12:plants12020301. [PMID: 36679017 PMCID: PMC9865629 DOI: 10.3390/plants12020301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/30/2022] [Accepted: 01/05/2023] [Indexed: 05/30/2023]
Abstract
Several specialized plant metabolites are reported to be enzyme inhibitors. In this investigation, the phytochemical composition and the biological activity of Rhanterium suaveolens Desf. were studied. One new lignan (rhanteriol 1) and seven known secondary metabolites were isolated from the aerial parts of R. suaveolens by using different chromatographic procedures. The biological properties of the R. suaveolens extracts and the new compound were evaluated by measuring their ability to inhibit the cholinesterase and carbohydrate-hydrolyzing enzymes, using cell-free in vitro methods. The new lignan, rhanteriol, was shown to inhibit α-amylase and α-glucosidase (IC50 = 46.42 ± 3.25 μM and 26.76 ± 3.29 μM, respectively), as well as butyrylcholinesterase (IC50 = 10.41 ± 0.03 μM), with an effect comparable to that of the respective standards, acarbose and galantamine. Furthermore, docking studies were performed suggesting the interaction mode of rhanteriol with the active sites of the investigated enzymes. The obtained data demonstrated that the aerial part of R. suaveolens could represent a source of active molecules, such as rhanteriol, usable in the development of treatments for preventing or treating type 2 diabetes mellitus and neurodegeneration.
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Affiliation(s)
- Soumia Belaabed
- Department of Chemistry, Research Unit, Development of Natural Resources, Bioactive Molecules, Physicochemical and Biological Analysis, University Mentouri, Route Ain ElBey, Constantine 25000, Algeria
| | - Ayoub Khalfaoui
- Department of Chemistry, Research Unit, Development of Natural Resources, Bioactive Molecules, Physicochemical and Biological Analysis, University Mentouri, Route Ain ElBey, Constantine 25000, Algeria
| | - Valentina Parisi
- Dipartimento di Farmacia, Università Degli Studi di Salerno, via Giovanni Paolo II 132, Fisciano, 84084 Salerno, Italy
- PhD Program in Drug Discovery and Development, Department of Pharmacy, University of Salerno, Via Giovanni Paolo II 132, Fisciano, 84084 Salerno, Italy
| | - Valentina Santoro
- Dipartimento di Farmacia, Università Degli Studi di Salerno, via Giovanni Paolo II 132, Fisciano, 84084 Salerno, Italy
| | - Daniela Russo
- Dipartimento di Scienze, Università Degli Studi Della Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy
- BioActiPlant s.r.l., Viale Dell’Ateneo Lucano 10, 85100 Potenza, Italy
| | - Maria Ponticelli
- Dipartimento di Scienze, Università Degli Studi Della Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy
| | - Magnus Monné
- Dipartimento di Scienze, Università Degli Studi Della Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy
| | - Khellaf Rebbas
- Natural and Life Sciences Department, Mohamed Boudiaf University, M’Sila 28000, Algeria
| | - Luigi Milella
- Dipartimento di Scienze, Università Degli Studi Della Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy
| | - Giuliana Donadio
- Dipartimento di Farmacia, Università Degli Studi di Salerno, via Giovanni Paolo II 132, Fisciano, 84084 Salerno, Italy
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Giuzio F, Bonomo MG, Catalano A, Infantino V, Salzano G, Monné M, Geronikaki A, Petrou A, Aquaro S, Sinicropi MS, Saturnino C. Potential PDE4B inhibitors as promising candidates against SARS-CoV-2 infection. Biomol Concepts 2023; 14:bmc-2022-0033. [PMID: 37909122 DOI: 10.1515/bmc-2022-0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/10/2023] [Indexed: 11/02/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an RNA virus belonging to the coronavirus family responsible for coronavirus disease 2019 (COVID-19). It primarily affects the pulmonary system, which is the target of chronic obstructive pulmonary disease (COPD), for which many new compounds have been developed. In this study, phosphodiesterase 4 (PDE4) inhibitors are being investigated. The inhibition of PDE4 enzyme produces anti-inflammatory and bronchodilator effects in the lung by inducing an increase in cAMP concentrations. Piclamilast and rolipram are known selective inhibitors of PDE4, which are unfortunately endowed with common side effects, such as nausea and emesis. The selective inhibition of the phosphodiesterase 4B (PDE4B) subtype may represent an intriguing technique for combating this highly contagious disease with fewer side effects. In this article, molecular docking studies for the selective inhibition of the PDE4B enzyme have been carried out on 21 in-house compounds. The compounds were docked into the pocket of the PDE4B catalytic site, and in most cases, they were almost completely superimposed onto piclamilast. Then, in order to enlarge our study, drug-likeness prediction studies were performed on the compounds under study.
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Affiliation(s)
- Federica Giuzio
- International PhD Programme 'Sciences', Department of Science, University of Basilicata, Viale dell'Ateneo Lucano n.10, 85100 Potenza, Italy
- Department of Science, University of Basilicata, 85100 Potenza, Italy
| | | | - Alessia Catalano
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70126 Bari, Italy
| | | | - Giovanni Salzano
- Department of Science, University of Basilicata, 85100 Potenza, Italy
| | - Magnus Monné
- Department of Science, University of Basilicata, 85100 Potenza, Italy
| | - Athina Geronikaki
- School of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Anthi Petrou
- School of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Stefano Aquaro
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
| | - Maria Stefania Sinicropi
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
| | - Carmela Saturnino
- Department of Science, University of Basilicata, 85100 Potenza, Italy
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Monné M, Marobbio CMT, Agrimi G, Palmieri L, Palmieri F. Mitochondrial transport and metabolism of the major methyl donor and versatile cofactor S-adenosylmethionine, and related diseases: A review †. IUBMB Life 2022; 74:573-591. [PMID: 35730628 DOI: 10.1002/iub.2658] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/19/2022] [Indexed: 11/08/2022]
Abstract
S-adenosyl-L-methionine (SAM) is a coenzyme and the most commonly used methyl-group donor for the modification of metabolites, DNA, RNA and proteins. SAM biosynthesis and SAM regeneration from the methylation reaction product S-adenosyl-L-homocysteine (SAH) take place in the cytoplasm. Therefore, the intramitochondrial SAM-dependent methyltransferases require the import of SAM and export of SAH for recycling. Orthologous mitochondrial transporters belonging to the mitochondrial carrier family have been identified to catalyze this antiport transport step: Sam5p in yeast, SLC25A26 (SAMC) in humans, and SAMC1-2 in plants. In mitochondria SAM is used by a vast number of enzymes implicated in the following processes: the regulation of replication, transcription, translation, and enzymatic activities; the maturation and assembly of mitochondrial tRNAs, ribosomes and protein complexes; and the biosynthesis of cofactors, such as ubiquinone, lipoate, and molybdopterin. Mutations in SLC25A26 and mitochondrial SAM-dependent enzymes have been found to cause human diseases, which emphasizes the physiological importance of these proteins.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,Department of Sciences, University of Basilicata, Potenza, Italy
| | - Carlo M T Marobbio
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Gennaro Agrimi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
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Miniero DV, Monné M, Di Noia MA, Palmieri L, Palmieri F. Evidence for Non-Essential Salt Bridges in the M-Gates of Mitochondrial Carrier Proteins. Int J Mol Sci 2022; 23:ijms23095060. [PMID: 35563451 PMCID: PMC9104175 DOI: 10.3390/ijms23095060] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial carriers, which transport metabolites, nucleotides, and cofactors across the mitochondrial inner membrane, have six transmembrane α-helices enclosing a translocation pore with a central substrate binding site whose access is controlled by a cytoplasmic and a matrix gate (M-gate). The salt bridges formed by the three PX[DE]XX[RK] motifs located on the odd-numbered transmembrane α-helices greatly contribute to closing the M-gate. We have measured the transport rates of cysteine mutants of the charged residue positions in the PX[DE]XX[RK] motifs of the bovine oxoglutarate carrier, the yeast GTP/GDP carrier, and the yeast NAD+ transporter, which all lack one of these charged residues. Most single substitutions, including those of the non-charged and unpaired charged residues, completely inactivated transport. Double mutations of charged pairs showed that all three carriers contain salt bridges non-essential for activity. Two double substitutions of these non-essential charge pairs exhibited higher transport rates than their corresponding single mutants, whereas swapping the charged residues in these positions did not increase activity. The results demonstrate that some of the residues in the charged residue positions of the PX[DE]XX[KR] motifs are important for reasons other than forming salt bridges, probably for playing specific roles related to the substrate interaction-mediated conformational changes leading to the M-gate opening/closing.
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Affiliation(s)
- Daniela Valeria Miniero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
- Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
| | - Maria Antonietta Di Noia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
- Correspondence: (L.P.); (F.P.)
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
- Correspondence: (L.P.); (F.P.)
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Palmieri F, Monné M, Fiermonte G, Palmieri L. Mitochondrial transport and metabolism of the vitamin B-derived cofactors thiamine pyrophosphate, coenzyme A, FAD and NAD + , and related diseases: A review. IUBMB Life 2022; 74:592-617. [PMID: 35304818 PMCID: PMC9311062 DOI: 10.1002/iub.2612] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 01/19/2023]
Abstract
Multiple mitochondrial matrix enzymes playing key roles in metabolism require cofactors for their action. Due to the high impermeability of the mitochondrial inner membrane, these cofactors need to be synthesized within the mitochondria or be imported, themselves or one of their precursors, into the organelles. Transporters belonging to the protein family of mitochondrial carriers have been identified to transport the coenzymes: thiamine pyrophosphate, coenzyme A, FAD and NAD+ , which are all structurally similar to nucleotides and derived from different B-vitamins. These mitochondrial cofactors bind more or less tightly to their enzymes and, after having been involved in a specific reaction step, are regenerated, spontaneously or by other enzymes, to return to their active form, ready for the next catalysis round. Disease-causing mutations in the mitochondrial cofactor carrier genes compromise not only the transport reaction but also the activity of all mitochondrial enzymes using that particular cofactor and the metabolic pathways in which the cofactor-dependent enzymes are involved. The mitochondrial transport, metabolism and diseases of the cofactors thiamine pyrophosphate, coenzyme A, FAD and NAD+ are the focus of this review.
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Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,Department of Sciences, University of Basilicata, Potenza, Italy
| | - Giuseppe Fiermonte
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
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Ostuni A, Monné M, Crudele MA, Cristinziano PL, Cecchini S, Amati M, De Vendel J, Raimondi P, Chassalevris T, Dovas CI, Bavoso A. Design and structural bioinformatic analysis of polypeptide antigens useful for the SRLV serodiagnosis. J Virol Methods 2021; 297:114266. [PMID: 34454989 DOI: 10.1016/j.jviromet.2021.114266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/30/2021] [Accepted: 08/18/2021] [Indexed: 10/20/2022]
Abstract
Due to their intrinsic genetic, structural and phenotypic variability the Lentiviruses, and specifically small ruminant lentiviruses (SRLV), are considered viral quasispecies with a population structure that consists of extremely large numbers of variant genomes, termed mutant spectra or mutant cloud. Immunoenzymatic tests for SRLVs are available but the dynamic heterogeneity of the virus makes the development of a diagnostic "golden standard" extremely difficult. The ELISA reported in the literature have been obtained using proteins derived from a single strain or they are multi-strain based assay that may increase the sensitivity of the serological diagnosis. Hundreds of SRLV protein sequences derived from different viral strains are deposited in GenBank. The aim of this study is to verify if the database can be exploited with the help of bioinformatics in order to have a more systematic approach in the design of a set of representative protein antigens useful in the SRLV serodiagnosis. Clustering, molecular modelling, molecular dynamics, epitope predictions and aggregative/solubility predictions were the main bioinformatic tools used. This approach led to the design of SRLV antigenic proteins that were expressed by recombinant DNA technology using synthetic genes, analyzed by CD spectroscopy, tested by ELISA and preliminarily compared to currently commercially available detection kits.
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Affiliation(s)
- Angela Ostuni
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100, Potenza, Italy.
| | - Magnus Monné
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100, Potenza, Italy
| | | | - Pier Luigi Cristinziano
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100, Potenza, Italy
| | - Stefano Cecchini
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100, Potenza, Italy
| | - Mario Amati
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100, Potenza, Italy
| | | | | | - Taxiarchis Chassalevris
- Diagnostic Laboratory, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 11 Stavrou Voutyra Str., 54627, Thessaloniki, Greece
| | - Chrysostomos I Dovas
- Diagnostic Laboratory, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 11 Stavrou Voutyra Str., 54627, Thessaloniki, Greece
| | - Alfonso Bavoso
- Department of Sciences, University of Basilicata, viale Ateneo Lucano 10, 85100, Potenza, Italy
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Faraone I, Russo D, Genovese S, Milella L, Monné M, Epifano F, Fiorito S. Screening of in vitro and in silico α-amylase, α-glucosidase, and lipase inhibitory activity of oxyprenylated natural compounds and semisynthetic derivatives. Phytochemistry 2021; 187:112781. [PMID: 33930668 DOI: 10.1016/j.phytochem.2021.112781] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 04/10/2021] [Accepted: 04/11/2021] [Indexed: 06/12/2023]
Abstract
Metabolic syndrome has several characteristic manifestations, including insulin resistance and dyslipidaemia, that demand therapeutic approaches, such as the inhibition of enzymes involved in nutrient absorption and digestion.This study aimed to evaluate the potential pharmacological use of natural compounds widespread in the plant kingdom and their semisynthetic compounds against target enzymes. Twenty-three oxyprenylated natural compoundswere investigated for their ability to inhibit α-amylase, α-glucosidase, and pancreatic lipase enzymes by in vitro assays. Moreover, in silico molecular docking was performed to analyse their binding capabilities into 3D structures. Farnesyloxyferulic acid, geranyloxyvanillic acid, nelumal A, and geranyloxyferulic acid showed the highest inhibition activity in all three in vitro enzyme assays. Moreover, in silico molecular docking of these four compounds was used to analyse their possible binding in 3D structures of the investigated enzymes. The results indicate that these compounds have considerable therapeutic potential for the treatment of metabolic syndrome, and further studies are warranted for their pharmacological development.
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Affiliation(s)
- Immacolata Faraone
- Department of Science, University of Basilicata, via dell'Ateneo Lucano 10, 85100, Potenza, Italy; SpinoffBioActiPlant s.r.l., via dell'Ateneo Lucano 10, 85100, Potenza, Italy
| | - Daniela Russo
- Department of Science, University of Basilicata, via dell'Ateneo Lucano 10, 85100, Potenza, Italy; SpinoffBioActiPlant s.r.l., via dell'Ateneo Lucano 10, 85100, Potenza, Italy
| | - Salvatore Genovese
- Department of Pharmacy, University Gabriele D'Annunzio of Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy
| | - Luigi Milella
- Department of Science, University of Basilicata, via dell'Ateneo Lucano 10, 85100, Potenza, Italy.
| | - Magnus Monné
- Department of Science, University of Basilicata, via dell'Ateneo Lucano 10, 85100, Potenza, Italy
| | - Francesco Epifano
- Department of Pharmacy, University Gabriele D'Annunzio of Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy.
| | - Serena Fiorito
- Department of Pharmacy, University Gabriele D'Annunzio of Chieti-Pescara, Via dei Vestini 31, 66100, Chieti Scalo, CH, Italy
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11
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Santoro V, Parisi V, D’Ambola M, Sinisgalli C, Monné M, Milella L, Russo R, Severino L, Braca A, Tommasi ND. Chemical Profiling of Astragalus membranaceus Roots (Fish.) Bunge Herbal Preparation and Evaluation of Its Bioactivity. Nat Prod Commun 2020. [DOI: 10.1177/1934578x20924152] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Astragalus membranaceus (Fish.) Bunge is a perennial herb distributed in the northern part of China, and its roots, namely, Hang qi, are included as a natural ingredient in dietary supplement formulations commonly used to treat different disorders such as respiratory infections, diabetes, and heart failure. The availability of a simple method for the determination of the quality of Astragalus herbal preparations could be a challenging issue for commercial purposes. In this study, a liquid chromatography–mass spectrometry (LC–MS)/MS based approach was used to characterize specialized metabolite recovery of 3 commercial hydroalcoholic extracts of A. membranaceus (AMG1, AMG2, AMG3) in addition to a hydroalcoholic extract of A. membranaceus root (AST). The hypoglycemic effect, cholinesterase inhibition, and antioxidant activities were also evaluated. Thirty-one compounds, of which 19 polyphenols and 12 saponins, were identified. The extracts were also quantified by using a sensitive and selective Q-Trap system for their content in flavonoids and astragalosides, selecting astragaloside I and IV as chemical markers. From our results, AMG3 preparation (Axtragyl) was the most abundant in terms of both specialized classes of metabolites, showing a fingerprint similar to that of AST. Interestingly, tested enzyme inhibition ability of flavonoids, daidzein (11) and formononetin (19), reported a higher α-glucosidase inhibition in comparison with that of acarbose used as positive control. The in silico study clarified the interactions among the molecules and the importance of having a free hydroxy group. Moreover, Axtragyl was able to exert protective effects in Caco-2 cells treated with hydrogen peroxide, confirming its ability as a potential protective agent in intestinal injury.
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Affiliation(s)
| | - Valentina Parisi
- Dipartimento di Farmacia, Università degli Studi di Salerno, Italy
| | | | | | - Magnus Monné
- Dipartimento di Scienze, Università della Basilicata, Italy
| | - Luigi Milella
- Dipartimento di Scienze, Università della Basilicata, Italy
| | | | - Lorella Severino
- Dipartimento di Medicina Veterinaria e Produzioni Animali, Università di Napoli, Italy
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12
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Palmieri F, Scarcia P, Monné M. Diseases Caused by Mutations in Mitochondrial Carrier Genes SLC25: A Review. Biomolecules 2020; 10:biom10040655. [PMID: 32340404 PMCID: PMC7226361 DOI: 10.3390/biom10040655] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 12/13/2022] Open
Abstract
In the 1980s, after the mitochondrial DNA (mtDNA) had been sequenced, several diseases resulting from mtDNA mutations emerged. Later, numerous disorders caused by mutations in the nuclear genes encoding mitochondrial proteins were found. A group of these diseases are due to defects of mitochondrial carriers, a family of proteins named solute carrier family 25 (SLC25), that transport a variety of solutes such as the reagents of ATP synthase (ATP, ADP, and phosphate), tricarboxylic acid cycle intermediates, cofactors, amino acids, and carnitine esters of fatty acids. The disease-causing mutations disclosed in mitochondrial carriers range from point mutations, which are often localized in the substrate translocation pore of the carrier, to large deletions and insertions. The biochemical consequences of deficient transport are the compartmentalized accumulation of the substrates and dysfunctional mitochondrial and cellular metabolism, which frequently develop into various forms of myopathy, encephalopathy, or neuropathy. Examples of diseases, due to mitochondrial carrier mutations are: combined D-2- and L-2-hydroxyglutaric aciduria, carnitine-acylcarnitine carrier deficiency, hyperornithinemia-hyperammonemia-homocitrillinuria (HHH) syndrome, early infantile epileptic encephalopathy type 3, Amish microcephaly, aspartate/glutamate isoform 1 deficiency, congenital sideroblastic anemia, Fontaine progeroid syndrome, and citrullinemia type II. Here, we review all the mitochondrial carrier-related diseases known until now, focusing on the connections between the molecular basis, altered metabolism, and phenotypes of these inherited disorders.
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Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
| | - Pasquale Scarcia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Department of Sciences, University of Basilicata, via Ateneo Lucano 10, 85100 Potenza, Italy
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
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13
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Faraone I, Russo D, Chiummiento L, Fernandez E, Choudhary A, Monné M, Milella L, Rai DK. Phytochemicals of Minthostachys diffusa Epling and Their Health-Promoting Bioactivities. Foods 2020; 9:foods9020144. [PMID: 32024045 PMCID: PMC7074199 DOI: 10.3390/foods9020144] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/21/2020] [Accepted: 01/23/2020] [Indexed: 12/31/2022] Open
Abstract
The genus Minthostachys belonging to the Lamiaceae family, and is an important South American mint genus used commonly in folk medicine as an aroma in cooking. The phytochemical-rich samples of the aerial parts of Minthostachys diffusa Epling. were tested for pharmacological and health-promoting bioactivities using in vitro chemical and enzymatic assays. A range of radical scavenging activities of the samples against biological radicals such as nitric oxide and superoxide anion and against synthetic 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, the ferric reducing antioxidant power and the lipid peroxidation inhibition were determined and ranked using the ‘relative antioxidant capacity index’ (RACI). The ethyl acetate fraction showed the highest RACI of +1.12. Analysis of the various fractions’ inhibitory ability against enzymes involved in diabetes (α-amylase and α-glucosidase), and against enzymes associated with Parkinson’s or Alzheimer’s diseases (acetylcholinesterase and butyrylcholinesterase) also suggested that the ethyl acetate fraction was the most active. Liquid chromatography–tandem mass spectrometry analysis of the ethyl acetate fraction showed more than 30 polyphenolic compounds, including triterpenes. The inhibitory cholinesterase effects of the triterpenes identified from M. diffusa were further analysed by in silico docking of these compounds into 3D-structures of acetylcholinesterase and butyrylcholinesterase. This is the first study on pharmacological activities and phytochemical profiling of the aerial parts of M. diffusa, showing that this plant, normally used as food in South America, is also rich in health-promoting phytochemicals.
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Affiliation(s)
- Immacolata Faraone
- Department of Science, University of Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy; (I.F.); (D.R.); (L.C.); (M.M.)
- Spinoff BioActiPlant s.r.l., Università della Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy
| | - Daniela Russo
- Department of Science, University of Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy; (I.F.); (D.R.); (L.C.); (M.M.)
- Spinoff BioActiPlant s.r.l., Università della Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy
| | - Lucia Chiummiento
- Department of Science, University of Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy; (I.F.); (D.R.); (L.C.); (M.M.)
| | - Eloy Fernandez
- Department of Crop Sciences and Agroforestry, Faculty of Tropical AgriSciences, Czech University of Life Sciences, Praha 6-Suchdol, Kamýcká 129, 16500 Prague, Czech Republic;
| | - Alka Choudhary
- Department of Food BioSciences, Teagasc Food Research Centre Ashtown, D15KN3K Dublin, Ireland; (A.C.); (D.K.R.)
| | - Magnus Monné
- Department of Science, University of Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy; (I.F.); (D.R.); (L.C.); (M.M.)
| | - Luigi Milella
- Department of Science, University of Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy; (I.F.); (D.R.); (L.C.); (M.M.)
- Spinoff BioActiPlant s.r.l., Università della Basilicata, V.le dell’Ateneo Lucano, 10, 85100 Potenza, Italy
- Correspondence: ; Tel./Fax: +39-0971-205525
| | - Dilip K. Rai
- Department of Food BioSciences, Teagasc Food Research Centre Ashtown, D15KN3K Dublin, Ireland; (A.C.); (D.K.R.)
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Gorgoglione R, Porcelli V, Santoro A, Daddabbo L, Vozza A, Monné M, Di Noia MA, Palmieri L, Fiermonte G, Palmieri F. The human uncoupling proteins 5 and 6 (UCP5/SLC25A14 and UCP6/SLC25A30) transport sulfur oxyanions, phosphate and dicarboxylates. Biochim Biophys Acta Bioenerg 2019; 1860:724-733. [PMID: 31356773 DOI: 10.1016/j.bbabio.2019.07.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/27/2019] [Accepted: 07/25/2019] [Indexed: 01/07/2023]
Abstract
The human genome encodes 53 members of the solute carrier family 25 (SLC25), also called the mitochondrial carrier family. In this work, two members of this family, UCP5 (BMCP1, brain mitochondrial carrier protein 1 encoded by SLC25A14) and UCP6 (KMCP1, kidney mitochondrial carrier protein 1 encoded by SLC25A30) have been thoroughly characterized biochemically. They were overexpressed in bacteria, purified and reconstituted in phospholipid vesicles. Their transport properties and kinetic parameters demonstrate that UCP5 and UCP6 transport inorganic anions (sulfate, sulfite, thiosulfate and phosphate) and, to a lesser extent, a variety of dicarboxylates (e.g. malonate, malate and citramalate) and, even more so, aspartate and (only UCP5) glutamate and tricarboxylates. Both carriers catalyzed a fast counter-exchange transport and a very low uniport of substrates. Transport was saturable and inhibited by mercurials and other mitochondrial carrier inhibitors at various degrees. The transport affinities of UCP5 and UCP6 were higher for sulfate and thiosulfate than for any other substrate, whereas the specific activity of UCP5 was much higher than that of UCP6. It is proposed that a main physiological role of UCP5 and UCP6 is to catalyze the export of sulfite and thiosulfate (the H2S degradation products) from the mitochondria, thereby modulating the level of the important signal molecule H2S.
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Affiliation(s)
- Ruggiero Gorgoglione
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Vito Porcelli
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Antonella Santoro
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Lucia Daddabbo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Angelo Vozza
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy; Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy; Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
| | - Maria Antonietta Di Noia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy; Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy; CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
| | - Giuseppe Fiermonte
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy; Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy.
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy; Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy; CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
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15
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Pop A, Williams M, Struys EA, Monné M, Jansen EEW, De Grassi A, Kanhai WA, Scarcia P, Ojeda MRF, Porcelli V, van Dooren SJM, Lennertz P, Nota B, Abdenur JE, Coman D, Das AM, El-Gharbawy A, Nuoffer JM, Polic B, Santer R, Weinhold N, Zuccarelli B, Palmieri F, Palmieri L, Salomons GS. An overview of combined D-2- and L-2-hydroxyglutaric aciduria: functional analysis of CIC variants. J Inherit Metab Dis 2018; 41:169-180. [PMID: 29238895 PMCID: PMC5830478 DOI: 10.1007/s10545-017-0106-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/15/2017] [Accepted: 10/18/2017] [Indexed: 11/13/2022]
Abstract
Combined D-2- and L-2-hydroxyglutaric aciduria (D/L-2-HGA) is a devastating neurometabolic disorder, usually lethal in the first years of life. Autosomal recessive mutations in the SLC25A1 gene, which encodes the mitochondrial citrate carrier (CIC), were previously detected in patients affected with combined D/L-2-HGA. We showed that transfection of deficient fibroblasts with wild-type SLC25A1 restored citrate efflux and decreased intracellular 2-hydroxyglutarate levels, confirming that deficient CIC is the cause of D/L-2-HGA. We developed and implemented a functional assay and applied it to all 17 missense variants detected in a total of 26 CIC-deficient patients, including eight novel cases, showing reduced activities of varying degrees. In addition, we analyzed the importance of residues affected by these missense variants using our existing scoring system. This allowed not only a clinical and biochemical overview of the D/L-2-HGA patients but also phenotype-genotype correlation studies.
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Affiliation(s)
- Ana Pop
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Monique Williams
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Eduard A Struys
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
- Department of Sciences, University of Basilicata, Potenza, Italy
| | - Erwin E W Jansen
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Anna De Grassi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Warsha A Kanhai
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Pasquale Scarcia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Matilde R Fernandez Ojeda
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Vito Porcelli
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Silvy J M van Dooren
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Pascal Lennertz
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Benjamin Nota
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands
| | - Jose E Abdenur
- Division of Metabolic Disorders, CHOC Children's, Orange, CA, USA
- Department of Pediatrics, University of California at Irvine, Irvine, CA, USA
| | - David Coman
- Department of Metabolic Medicine, Lady Cilento Children's Hospital, Brisbane, Australia
- School of Medicine, University of Queensland Brisbane, Griffith University Gold Coast, Gold Coast, Australia
| | - Anibh Martin Das
- Clinic for Pediatric Kidney-, Liver- and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Areeg El-Gharbawy
- Department of Pediatrics and Division of Medical Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jean-Marc Nuoffer
- Division of Pediatric Endocrinology, Diabetology and Metabolism and University Institute of Clinical Chemistry, Inselspital, University Hospital, University of Bern, Bern, Switzerland
| | - Branka Polic
- Department of Pediatrics, PICU, University Hospital Centre, Split, Croatia
| | - René Santer
- Department of Pediatrics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Natalie Weinhold
- Sozialpädiatrisches Zentrum, Charité Universitätsmedizin Berlin, Berlin, Germany
| | | | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnology, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnology, Consiglio Nazionale delle Ricerche, Bari, Italy.
| | - Gajja S Salomons
- Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center Metabolic Unit PK 1X009, Postbus 7057, 1007 MB, Amsterdam, The Netherlands.
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16
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Monné M, Daddabbo L, Gagneul D, Obata T, Hielscher B, Palmieri L, Miniero DV, Fernie AR, Weber APM, Palmieri F. Uncoupling proteins 1 and 2 (UCP1 and UCP2) from Arabidopsis thaliana are mitochondrial transporters of aspartate, glutamate, and dicarboxylates. J Biol Chem 2018; 293:4213-4227. [PMID: 29371401 DOI: 10.1074/jbc.ra117.000771] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/15/2018] [Indexed: 12/29/2022] Open
Abstract
The Arabidopsis thaliana genome contains 58 members of the solute carrier family SLC25, also called the mitochondrial carrier family, many of which have been shown to transport specific metabolites, nucleotides, and cofactors across the mitochondrial membrane. Here, two Arabidopsis members of this family, AtUCP1 and AtUCP2, which were previously thought to be uncoupling proteins and hence named UCP1/PUMP1 and UCP2/PUMP2, respectively, are assigned with a novel function. They were expressed in bacteria, purified, and reconstituted in phospholipid vesicles. Their transport properties demonstrate that they transport amino acids (aspartate, glutamate, cysteine sulfinate, and cysteate), dicarboxylates (malate, oxaloacetate, and 2-oxoglutarate), phosphate, sulfate, and thiosulfate. Transport was saturable and inhibited by mercurials and other mitochondrial carrier inhibitors to various degrees. AtUCP1 and AtUCP2 catalyzed a fast counterexchange transport as well as a low uniport of substrates, with transport rates of AtUCP1 being much higher than those of AtUCP2 in both cases. The aspartate/glutamate heteroexchange mediated by AtUCP1 and AtUCP2 is electroneutral, in contrast to that mediated by the mammalian mitochondrial aspartate glutamate carrier. Furthermore, both carriers were found to be targeted to mitochondria. Metabolite profiling of single and double knockouts shows changes in organic acid and amino acid levels. Notably, AtUCP1 and AtUCP2 are the first reported mitochondrial carriers in Arabidopsis to transport aspartate and glutamate. It is proposed that the primary function of AtUCP1 and AtUCP2 is to catalyze an aspartateout/glutamatein exchange across the mitochondrial membrane and thereby contribute to the export of reducing equivalents from the mitochondria in photorespiration.
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Affiliation(s)
- Magnus Monné
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, via Orabona 4, 70125 Bari, Italy.,the Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
| | - Lucia Daddabbo
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - David Gagneul
- the Cluster of Excellence on Plant Science (CEPLAS), Institute of Plant Biochemistry, Heinrich-Heine-Universität, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Toshihiro Obata
- the Department Willmitzer, Max-Planck-Institut fur Molekulare Pflanzenphysiologie, Am Muhlenberg 1, 14476 Potsdam-Golm, Germany, and
| | - Björn Hielscher
- the Cluster of Excellence on Plant Science (CEPLAS), Institute of Plant Biochemistry, Heinrich-Heine-Universität, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Luigi Palmieri
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, via Orabona 4, 70125 Bari, Italy.,the Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Daniela Valeria Miniero
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Alisdair R Fernie
- the Department Willmitzer, Max-Planck-Institut fur Molekulare Pflanzenphysiologie, Am Muhlenberg 1, 14476 Potsdam-Golm, Germany, and
| | - Andreas P M Weber
- the Cluster of Excellence on Plant Science (CEPLAS), Institute of Plant Biochemistry, Heinrich-Heine-Universität, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Ferdinando Palmieri
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, via Orabona 4, 70125 Bari, Italy, .,the Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy
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Monné M, Daddabbo L, Giannossa LC, Nicolardi MC, Palmieri L, Miniero DV, Mangone A, Palmieri F. Mitochondrial ATP-Mg/phosphate carriers transport divalent inorganic cations in complex with ATP. J Bioenerg Biomembr 2017; 49:369-380. [PMID: 28695448 DOI: 10.1007/s10863-017-9721-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 06/22/2017] [Indexed: 12/16/2022]
Abstract
The ATP-Mg/phosphate carriers (APCs) modulate the intramitochondrial adenine nucleotide pool size. In this study the concentration-dependent effects of Mg2+ and other divalent cations (Me2+) on the transport of [3H]ATP in liposomes reconstituted with purified human and Arabidopsis APCs (hAPCs and AtAPCs, respectively, including some lacking their N-terminal domains) have been investigated. The transport of Me2+ mediated by these proteins was also measured. In the presence of a low external concentration of [3H]ATP (12 μM) and increasing concentrations of Me2+, Mg2+ stimulated the activity (measured as initial transport rate of [3H]ATP) of hAPCs and decreased that of AtAPCs; Fe2+ and Zn2+ stimulated markedly hAPCs and moderately AtAPCs; Ca2+ and Mn2+ markedly AtAPCs and moderately hAPCs; and Cu2+ decreased the activity of both hAPCs and AtAPCs. All the Me2+-dependent effects correlated well with the amount of ATP-Me complex present. The transport of [14C]AMP, which has a much lower ability of complexation than ATP, was not affected by the presence of the Me2+ tested, except Cu2+. Furthermore, the transport of [3H]ATP catalyzed by the ATP/ADP carrier, which is known to transport only free ATP and ADP, was inhibited by all the Me2+ tested in an inverse relationship with the formation of the ATP-Me complex. Finally, direct measurements of Mg2+, Mn2+, Fe2+, Zn2+ and Cu2+ showed that they are cotransported with ATP by both hAPCs and AtAPCs. It is likely that in vivo APCs transport free ATP and ATP-Mg complex to different degrees, and probably trace amounts of other Me2+ in complex with ATP.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy.,Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100, Potenza, Italy
| | - Lucia Daddabbo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy
| | | | - Maria Cristina Nicolardi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy.,Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, Consiglio Nazionale delle Ricerche, 70126, Bari, Italy
| | - Daniela Valeria Miniero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy
| | - Annarosa Mangone
- Department of Chemistry, University of Bari, Via E. Orabona 4, 70126, Bari, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy. .,Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, Consiglio Nazionale delle Ricerche, 70126, Bari, Italy.
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Miglionico R, Gerbino A, Ostuni A, Armentano MF, Monné M, Carmosino M, Bisaccia F. Erratum to: New insights into the roles of the N-terminal region of the ABCC6 transporter. J Bioenerg Biomembr 2016; 48:335. [DOI: 10.1007/s10863-016-9661-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Palmieri F, Monné M. Discoveries, metabolic roles and diseases of mitochondrial carriers: A review. Biochim Biophys Acta 2016; 1863:2362-78. [PMID: 26968366 DOI: 10.1016/j.bbamcr.2016.03.007] [Citation(s) in RCA: 153] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/25/2022]
Abstract
Mitochondrial carriers (MCs) are a superfamily of nuclear-encoded proteins that are mostly localized in the inner mitochondrial membrane and transport numerous metabolites, nucleotides, cofactors and inorganic anions. Their unique sequence features, i.e., a tripartite structure, six transmembrane α-helices and a three-fold repeated signature motif, allow MCs to be easily recognized. This review describes how the functions of MCs from Saccharomyces cerevisiae, Homo sapiens and Arabidopsis thaliana (listed in the first table) were discovered after the genome sequence of S. cerevisiae was determined in 1996. In the genomic era, more than 50 previously unknown MCs from these organisms have been identified and characterized biochemically using a method consisting of gene expression, purification of the recombinant proteins, their reconstitution into liposomes and transport assays (EPRA). Information derived from studies with intact mitochondria, genetic and metabolic evidence, sequence similarity, phylogenetic analysis and complementation of knockout phenotypes have guided the choice of substrates that were tested in the transport assays. In addition, the diseases associated to defects of human MCs have been briefly reviewed. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
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Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
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Grossi G, Grimaldi A, Cardone RA, Monné M, Reshkin SJ, Girardello R, Greco MR, Coviello E, Laurino S, Falabella P. Extracellular matrix degradation via enolase/plasminogen interaction: Evidence for a mechanism conserved in Metazoa. Biol Cell 2016; 108:161-78. [PMID: 26847147 DOI: 10.1111/boc.201500095] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 01/29/2016] [Indexed: 01/21/2023]
Abstract
BACKGROUND INFORMATION While enolase is a ubiquitous metalloenzyme involved in the glycolytic pathway, it is also known as a multifunctional protein, since enolases anchored on the outer surface of the plasma membrane are involved in tissue invasion. RESULTS We have identified an extracellular enolase (Ae-ENO) produced by the teratocytes, embryonic cells of the insect parasitoid Aphidius ervi. We demonstrate that Ae-ENO, although lacking a signal peptide, accumulates in cytoplasmic vesicles oriented towards the cell membrane. Ae-ENO binds to and activates a plasminogen-like molecule inducing digestion of the host tissue and thereby ensuring successful parasitism. CONCLUSIONS These results support the hypothesis that plasminogen-like proteins exist in invertebrates. Interestingly the activation of a plasminogen-like protein is mediated by a mechanisms involving the surface enolase/fibrinolytic system considered, until now, exclusive of vertebrates, and that instead is conserved across species. SIGNIFICANCE To our knowledge, this is the first example of enolase mediated Plg-like binding and activation in insect cells, demonstrating the existence of an ECM degradation process via a Plg-like protein in invertebrates.
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Affiliation(s)
- Gerarda Grossi
- Department of Sciences, University of Basilicata, Potenza, 85100, Italy
| | - Annalisa Grimaldi
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, 21100, Italy
| | - Rosa A Cardone
- Department of Bioscience, Biotechnologies and Biopharmaceutics, University of Bari, Bari, 70126, Italy
| | - Magnus Monné
- Department of Sciences, University of Basilicata, Potenza, 85100, Italy
| | - Stephan J Reshkin
- Department of Bioscience, Biotechnologies and Biopharmaceutics, University of Bari, Bari, 70126, Italy
| | - Rossana Girardello
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, 21100, Italy
| | - Maria R Greco
- Department of Bioscience, Biotechnologies and Biopharmaceutics, University of Bari, Bari, 70126, Italy
| | - Elena Coviello
- Department of Sciences, University of Basilicata, Potenza, 85100, Italy
| | - Simona Laurino
- Department of Sciences, University of Basilicata, Potenza, 85100, Italy
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Kishita Y, Pajak A, Bolar NA, Marobbio CMT, Maffezzini C, Miniero DV, Monné M, Kohda M, Stranneheim H, Murayama K, Naess K, Lesko N, Bruhn H, Mourier A, Wibom R, Nennesmo I, Jespers A, Govaert P, Ohtake A, Van Laer L, Loeys BL, Freyer C, Palmieri F, Wredenberg A, Okazaki Y, Wedell A. Intra-mitochondrial Methylation Deficiency Due to Mutations in SLC25A26. Am J Hum Genet 2015; 97:761-8. [PMID: 26522469 PMCID: PMC4667130 DOI: 10.1016/j.ajhg.2015.09.013] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/29/2015] [Indexed: 01/24/2023] Open
Abstract
S-adenosylmethionine (SAM) is the predominant methyl group donor and has a large spectrum of target substrates. As such, it is essential for nearly all biological methylation reactions. SAM is synthesized by methionine adenosyltransferase from methionine and ATP in the cytoplasm and subsequently distributed throughout the different cellular compartments, including mitochondria, where methylation is mostly required for nucleic-acid modifications and respiratory-chain function. We report a syndrome in three families affected by reduced intra-mitochondrial methylation caused by recessive mutations in the gene encoding the only known mitochondrial SAM transporter, SLC25A26. Clinical findings ranged from neonatal mortality resulting from respiratory insufficiency and hydrops to childhood acute episodes of cardiopulmonary failure and slowly progressive muscle weakness. We show that SLC25A26 mutations cause various mitochondrial defects, including those affecting RNA stability, protein modification, mitochondrial translation, and the biosynthesis of CoQ10 and lipoic acid.
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Affiliation(s)
- Yoshihito Kishita
- Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University, 1397-1 Yamane, Hidaka-shi, Saitama 350-1241, Japan
| | - Aleksandra Pajak
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Nikhita Ajit Bolar
- Department of Medical Genetics, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp 2650, Belgium
| | - Carlo M T Marobbio
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Edoardo Orabona 4, 70125 Bari, Italy
| | - Camilla Maffezzini
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Daniela V Miniero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Edoardo Orabona 4, 70125 Bari, Italy
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Edoardo Orabona 4, 70125 Bari, Italy; Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
| | - Masakazu Kohda
- Division of Translational Research, Research Center for Genomic Medicine, Saitama Medical University, 1397-1 Yamane, Hidaka-shi, Saitama 350-1241, Japan
| | - Henrik Stranneheim
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden; Science for Life Laboratory and Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Kei Murayama
- Department of Metabolism, Chiba Children's Hospital, 579-1 Heta-cho, Midori, Chiba 266-0007, Japan
| | - Karin Naess
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden; Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Nicole Lesko
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden; Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Helene Bruhn
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden; Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Arnaud Mourier
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Rolf Wibom
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden; Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Inger Nennesmo
- Department of Pathology, Karolinska University Hospital, 171 77 Stockholm, Sweden
| | - Ann Jespers
- Paola Children's Hospital, ZNA Middelheim, Antwerp 2650, Belgium
| | - Paul Govaert
- Paola Children's Hospital, ZNA Middelheim, Antwerp 2650, Belgium
| | - Akira Ohtake
- Department of Pediatrics, Saitama Medical University, 38 Morohongo Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan
| | - Lut Van Laer
- Department of Medical Genetics, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp 2650, Belgium
| | - Bart L Loeys
- Department of Medical Genetics, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp 2650, Belgium; Department of Genetics, Radboud University Medical Center, Nijmegen, 6525 GA, the Netherlands
| | - Christoph Freyer
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden; Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Edoardo Orabona 4, 70125 Bari, Italy.
| | - Anna Wredenberg
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden; Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden.
| | - Yasushi Okazaki
- Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University, 1397-1 Yamane, Hidaka-shi, Saitama 350-1241, Japan; Division of Translational Research, Research Center for Genomic Medicine, Saitama Medical University, 1397-1 Yamane, Hidaka-shi, Saitama 350-1241, Japan
| | - Anna Wedell
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Division of Metabolic Diseases, Department of Laboratory Medicine, Karolinska Institutet, 171 77 Stockholm, Sweden; Centre for Inherited Metabolic Diseases, Karolinska University Hospital, 171 76 Stockholm, Sweden; Science for Life Laboratory and Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden
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22
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Cuviello F, Tellgren-Roth Å, Lara P, Ruud Selin F, Monné M, Bisaccia F, Nilsson I, Ostuni A. Membrane insertion and topology of the amino-terminal domain TMD0 of multidrug-resistance associated protein 6 (MRP6). FEBS Lett 2015; 589:3921-8. [PMID: 26545497 DOI: 10.1016/j.febslet.2015.10.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/20/2015] [Accepted: 10/26/2015] [Indexed: 01/25/2023]
Abstract
The function of the ATP-binding cassette transporter MRP6 is unknown but mutations in its gene cause pseudoxanthoma elasticum. We have investigated the membrane topology of the N-terminal transmembrane domain TMD0 of MRP6 and the membrane integration and orientation propensities of its transmembrane segments (TMs) by glycosylation mapping. Results demonstrate that TMD0 has five TMs, an Nout-Cin topology and that the less hydrophobic TMs have strong preference for their orientation in the membrane that affects the neighboring TMs. Two disease-causing mutations changing the number of positive charges in the loops of TMD0 did not affect the membrane insertion efficiencies of the adjacent TMs.
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Affiliation(s)
- Flavia Cuviello
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy
| | - Åsa Tellgren-Roth
- Department of Biochemistry and Biophysics, Stockholm University, 106 91 Stockholm, Sweden
| | - Patricia Lara
- Department of Biochemistry and Biophysics, Stockholm University, 106 91 Stockholm, Sweden
| | - Frida Ruud Selin
- Department of Biochemistry and Biophysics, Stockholm University, 106 91 Stockholm, Sweden
| | - Magnus Monné
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy
| | - Faustino Bisaccia
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy
| | - IngMarie Nilsson
- Department of Biochemistry and Biophysics, Stockholm University, 106 91 Stockholm, Sweden.
| | - Angela Ostuni
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy.
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Monné M, Miniero DV, Daddabbo L, Palmieri L, Porcelli V, Palmieri F. Mitochondrial transporters for ornithine and related amino acids: a review. Amino Acids 2015; 47:1763-77. [PMID: 26002808 DOI: 10.1007/s00726-015-1990-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 04/15/2015] [Indexed: 12/18/2022]
Abstract
Among the members of the mitochondrial carrier family, there are transporters that catalyze the translocation of ornithine and related substrates, such as arginine, homoarginine, lysine, histidine, and citrulline, across the inner mitochondrial membrane. The mitochondrial carriers ORC1, ORC2, and SLC25A29 from Homo sapiens, BAC1 and BAC2 from Arabidopsis thaliana, and Ort1p from Saccharomyces cerevisiae have been biochemically characterized by transport assays in liposomes. All of them transport ornithine and amino acids with side chains terminating at least with one amine. There are, however, marked differences in their substrate specificities including their affinity for ornithine (KM values in the mM to μM range). These differences are most likely reflected by minor differences in the substrate binding sites of these carriers. The physiological role of the above-mentioned mitochondrial carriers is to link several metabolic pathways that take place partly in the cytosol and partly in the mitochondrial matrix and to provide basic amino acids for mitochondrial translation. In the liver, human ORC1 catalyzes the citrulline/ornithine exchange across the mitochondrial inner membrane, which is required for the urea cycle. Human ORC1, ORC2, and SLC25A29 are likely to be involved in the biosynthesis and transport of arginine, which can be used as a precursor for the synthesis of NO, agmatine, polyamines, creatine, glutamine, glutamate, and proline, as well as in the degradation of basic amino acids. BAC1 and BAC2 are implicated in some processes similar to those of their human counterparts and in nitrogen and amino acid metabolism linked to stress conditions and the development of plants. Ort1p is involved in the biosynthesis of arginine and polyamines in yeast.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125, Bari, Italy
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Martinelli D, Diodato D, Ponzi E, Monné M, Boenzi S, Bertini E, Fiermonte G, Dionisi-Vici C. The hyperornithinemia-hyperammonemia-homocitrullinuria syndrome. Orphanet J Rare Dis 2015; 10:29. [PMID: 25874378 PMCID: PMC4358699 DOI: 10.1186/s13023-015-0242-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/13/2015] [Indexed: 02/07/2023] Open
Abstract
Background Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a rare autosomal recessive disorder of the urea cycle. HHH has a panethnic distribution, with a major prevalence in Canada, Italy and Japan. Acute clinical signs include intermittent episodes of vomiting, confusion or coma and hepatitis-like attacks. Alternatively, patients show a chronic course with aversion for protein rich foods, developmental delay/intellectual disability, myoclonic seizures, ataxia and pyramidal dysfunction. HHH syndrome is caused by impaired ornithine transport across the inner mitochondrial membrane due to mutations in SLC25A15 gene, which encodes for the mitochondrial ornithine carrier ORC1. The diagnosis relies on clinical signs and the peculiar metabolic triad of hyperammonemia, hyperornithinemia, and urinary excretion of homocitrulline. HHH syndrome enters in the differential diagnosis with other inherited or acquired conditions presenting with hyperammonemia. Methods A systematic review of publications reporting patients with HHH syndrome was performed. Results We retrospectively evaluated the clinical, biochemical and genetic profile of 111 HHH syndrome patients, 109 reported in 61 published articles, and two unpublished cases. Lethargy and coma are frequent at disease onset, whereas pyramidal dysfunction and cognitive/behavioural abnormalities represent the most common clinical features in late-onset cases or during the disease course. Two common mutations, F188del and R179* account respectively for about 30% and 15% of patients with the HHH syndrome. Interestingly, the majority of mutations are located in residues that have side chains protruding into the internal pore of ORC1, suggesting their possible interference with substrate translocation. Acute and chronic management consists in the control of hyperammonemia with protein-restricted diet supplemented with citrulline/arginine and ammonia scavengers. Prognosis of HHH syndrome is variable, ranging from a severe course with disabling manifestations to milder variants compatible with an almost normal life. Conclusions This paper provides detailed information on the clinical, metabolic and genetic profiles of all HHH syndrome patients published to date. The clinical phenotype is extremely variable and its severity does not correlate with the genotype or with recorded ammonium/ornithine plasma levels. Early intervention allows almost normal life span but the prognosis is variable, suggesting the need for a better understanding of the still unsolved pathophysiology of the disease. Electronic supplementary material The online version of this article (doi:10.1186/s13023-015-0242-9) contains supplementary material, which is available to authorized users.
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Abstract
The eukaryotic transport protein family SLC25 consists of mitochondrial carriers (MCs) that are recognized on the sequence level by a threefold repeated and conserved signature motif. The majority of MCs characterized so far catalyzes strict exchanges of substrates across the mitochondrial inner membrane. The substrates are nucleotides, metabolic intermediates, and cofactors that are required in cytoplasmic and matrix metabolism. This review summarizes and discusses the current knowledge of the antiport mechanism(s) of MCs that has been deduced from determining transport characteristics and by analyzing structural, sequence, and mutagenesis data. The mode of transport varies among different MCs with respect to how the substrate translocation depends on the electrical and pH gradients across the mitochondrial inner membrane, for example, the ADP/ATP carrier is electrogenic (electrophoretic), the GTP/GDP carrier is dependent on the pH gradient, the aspartate/glutamate carrier is dependent on both, and the oxoglutarate/malate carrier is independent of them. The structure of the bovine ADP/ATP carrier consists of a six-transmembrane α-helix bundle with a pseudo-threefold symmetry and a closed matrix gate. By using this structure as a template in homology modeling, residues engaged in substrate binding and the formation of a cytoplasmic gate in MCs have been proposed. The functional importance of the residues of the binding site, the matrix, and the cytoplasmic gates is supported by transport activities of different MCs with single point mutations. Cumulative evidence has been used to postulate a general transport mechanism for MCs.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnology and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, Bari, Italy; Department of Sciences, University of Basilicata, Potenza, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnology and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari, Bari, Italy.
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Pascale M, Laurino S, Vogel H, Grimaldi A, Monné M, Riviello L, Tettamanti G, Falabella P. The Lepidopteran endoribonuclease-U domain protein P102 displays dramatically reduced enzymatic activity and forms functional amyloids. Dev Comp Immunol 2014; 47:129-39. [PMID: 25043263 PMCID: PMC7124382 DOI: 10.1016/j.dci.2014.07.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 07/08/2014] [Accepted: 07/09/2014] [Indexed: 06/03/2023]
Abstract
Hemocytes of Heliothis virescens (F.) (Lepidoptera, Noctuidae) larvae produce a protein, P102, with a putative endoribonuclease-U domain. In previous works we have shown that P102 is involved in Lepidopteran immune response by forming amyloid fibrils, which catalyze and localize melanin deposition around non-self intruders during encapsulation, preventing harmful systemic spreading. Here we demonstrate that P102 belongs to a new class of proteins that, at least in Lepidoptera, has a diminished endoribonuclease-U activity probably due to the lack of two out of five catalytically essential residues. We show that the P102 homolog from Trichoplusia ni (Lepidoptera, Noctuidae) displays catalytic site residues identical to P102, a residual endoribonuclease-U activity and the ability to form functional amyloids. On the basis of these results as well as sequence and structural analyses, we hypothesize that all the Lepidoptera endoribonuclease-U orthologs with catalytic site residues identical to P102 form a subfamily with similar function.
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Affiliation(s)
- Mariarosa Pascale
- Università della Basilicata, Dipartimento di Scienze, via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Simona Laurino
- Università della Basilicata, Dipartimento di Scienze, via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Heiko Vogel
- Department of Entomology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany
| | - Annalisa Grimaldi
- Università dell'Insubria, Dipartimento di Biotecnologie e Scienze della Vita, via Dunant 3, 21100 Varese, Italy
| | - Magnus Monné
- Università della Basilicata, Dipartimento di Scienze, via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Lea Riviello
- Università della Basilicata, Dipartimento di Scienze, via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Gianluca Tettamanti
- Università dell'Insubria, Dipartimento di Biotecnologie e Scienze della Vita, via Dunant 3, 21100 Varese, Italy
| | - Patrizia Falabella
- Università della Basilicata, Dipartimento di Scienze, via dell'Ateneo Lucano 10, 85100 Potenza, Italy.
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Ostuni A, Lara P, Armentano MF, Miglionico R, Salvia AM, Mönnich M, Carmosino M, Lasorsa FM, Monné M, Nilsson I, Bisaccia F. The hepatitis B x antigen anti-apoptotic effector URG7 is localized to the endoplasmic reticulum membrane. FEBS Lett 2013; 587:3058-62. [PMID: 23912081 DOI: 10.1016/j.febslet.2013.07.042] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 07/16/2013] [Accepted: 07/19/2013] [Indexed: 11/29/2022]
Abstract
Hepatitis B x antigen up-regulates the liver expression of URG7 that contributes to sustain chronic virus infection and to increase the risk for hepatocellular carcinoma by its anti-apoptotic activity. We have investigated the subcellular localization of URG7 expressed in HepG2 cells and determined its membrane topology by glycosylation mapping in vitro. The results demonstrate that URG7 is N-glycosylated and located to the endoplasmic reticulum membrane with an Nlumen-Ccytosol orientation. The results imply that the anti-apoptotic effect of URG7 could arise from the C-terminal cytosolic tail binding a pro-apoptotic signaling factor and retaining it to the endoplasmic reticulum membrane.
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Affiliation(s)
- A Ostuni
- Department of Sciences, University of Basilicata, 85100 Potenza, Italy
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Abstract
The 2-oxoglutarate carrier (OGC) belongs to the mitochondrial carrier protein family whose members are responsible for the exchange of metabolites, cofactors and nucleotides between the cytoplasm and mitochondrial matrix. Initially, OGC was characterized by determining substrate specificity, kinetic parameters of transport, inhibitors and molecular probes that form covalent bonds with specific residues. It was shown that OGC specifically transports oxoglutarate and certain carboxylic acids. The substrate specificity combination of OGC is unique, although many of its substrates are also transported by other mitochondrial carriers. The abundant recombinant expression of bovine OGC in Escherichia coli and its ability to functionally reconstitute into proteoliposomes made it possible to deduce the individual contribution of each and every residue of OGC to the transport activity by a complete set of cys-scanning mutants. These studies give experimental support for a substrate binding site constituted by three major contact points on the even-numbered α-helices and identifies other residues as important for transport function through their crucial positions in the structure for conserved interactions and the conformational changes of the carrier during the transport cycle. The results of these investigations have led to utilize OGC as a model protein for understanding the transport mechanism of mitochondrial carriers.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnology and Pharmacological Sciences, Laboratory of Biochemistry and Molecular Biology, University of Bari, Via E. Orabona 4, 70125 Bari, Italy.
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Monné M, Miniero DV, Iacobazzi V, Bisaccia F, Fiermonte G. Erratum to: The mitochondrial oxoglutarate carrier: from identification to mechanism. J Bioenerg Biomembr 2012. [DOI: 10.1007/s10863-012-9487-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
Mitochondrial carriers transport inorganic ions, nucleotides, amino acids, keto acids and cofactors across the mitochondrial inner membrane. Structurally they consist of three domains, each containing two transmembrane α-helices linked by a short α-helix and loop. The substrate binds to three major contact points in the central cavity. The class of substrate (e.g., adenine nucleotides) is determined by contact point II on transmembrane α-helix H4 and the type of substrate within the class (e.g., ADP, coenzyme A) by contact point I in H2, whereas contact point III on H6 is most usually a positively charged residue, irrespective of the type or class. Two salt bridge networks, consisting of conserved and symmetric residues, are located on the matrix and cytoplasmic side of the cavity. These residues are part of the gates that are involved in opening and closing of the carrier during the transport cycle, exposing the central substrate binding site to either side of the membrane in an alternating way. Here we revisit the plethora of mutagenesis data that have been collected over the last two decades to see if the residues in the proposed binding site and salt bridge networks are indeed important for function. The analysis shows that the major contact points of the substrate binding site are indeed crucial for function and in defining the specificity. The matrix salt bridge network is more critical for function than the cytoplasmic salt bridge network in agreement with its central position, but neither is likely to be involved in substrate recognition directly.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnology and Pharmacological Sciences, Laboratory of Biochemistry and Molecular Biology, University of Bari, Bari, Italy
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Monné M, Miniero DV, Daddabbo L, Robinson AJ, Kunji ERS, Palmieri F. Substrate specificity of the two mitochondrial ornithine carriers can be swapped by single mutation in substrate binding site. J Biol Chem 2012; 287:7925-34. [PMID: 22262851 DOI: 10.1074/jbc.m111.324855] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mitochondrial carriers are a large family of proteins that transport specific metabolites across the inner mitochondrial membrane. Sequence and structure analysis has indicated that these transporters have substrate binding sites in a similar location of the central cavity consisting of three major contact points. Here we have characterized mutations of the proposed substrate binding site in the human ornithine carriers ORC1 and ORC2 by carrying out transport assays with a set of different substrates. The different substrate specificities of the two isoforms, which share 87% identical amino acids, were essentially swapped by exchanging a single residue located at position 179 that is arginine in ORC1 and glutamine in ORC2. Altogether the substrate specificity changes demonstrate that Arg-179 and Glu-180 of contact point II bind the C(α) carboxylate and amino group of the substrates, respectively. Residue Glu-77 of contact point I most likely interacts with the terminal amino group of the substrate side chain. Furthermore, it is likely that all three contact points are involved in the substrate-induced conformational changes required for substrate translocation because Arg-179 is probably connected with Arg-275 of contact point III through Trp-224 by cation-π interactions. Mutations at position 179 also affected the turnover number of the ornithine carrier severely, implying that substrate binding to residue 179 is a rate-limiting step of the catalytic transport cycle. Given that Arg-179 is located in the vicinity of the matrix gate, it is concluded that it is a key residue in the opening of the carrier to the matrix side.
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Affiliation(s)
- Magnus Monné
- Department of Pharmaco-Biology, Laboratory of Biochemistry and Molecular Biology, University of Bari, Via E. Orabona 4, 70125 Bari, Italy
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Ostuni A, Miglionico R, Monné M, Castiglione Morelli MA, Bisaccia F. The nucleotide-binding domain 2 of the human transporter protein MRP6. J Bioenerg Biomembr 2011; 43:465-71. [PMID: 21748403 DOI: 10.1007/s10863-011-9372-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 06/13/2011] [Indexed: 02/03/2023]
Abstract
Multidrug-resistance-associated protein 6 (MRP6/ABCC6) belongs to the ABC transporter family, whose members share many characteristic features including membrane domains and two nucleotide-binding domains (NBD1 and NBD2). These function cooperatively to bind and hydrolyze ATP for the transport of substrates across biological membranes. In this study, MRP6-NBD2 (residues 1252-1503) was expressed in Escherichia coli, purified and structurally and functionally characterized. CD spectra suggested that the protein is folded. Furthermore, NBD2 is shown to be biologically active as it binds ATP and presents ATPase activity although significantly lower compared with isolated NBD1. The mixture of NBD2 and NBD1 exhibited an activity similar to the NBD2 alone, indicating that NBD1 and NBD2 form a heterodimer with the latter limiting ATP hydrolysis. These findings suggest that NBD1 has a higher tendency to form an active homodimer, which is also supported by in silico analysis of energy-minimized dimers of the homology models of the two domains.
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Affiliation(s)
- Angela Ostuni
- Department of Chemistry "Antonio Mario Tamburro", University of Basilicata, viale Ateneo Lucano 10, 85100 Potenza, Italy.
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Abstract
Species-restricted interaction between gametes at the beginning of fertilization is mediated by the extracellular coat of the egg, a matrix of cross-linked glycoprotein filaments called the zona pellucida (ZP) in mammals and the vitelline envelope in nonmammals. All egg coat subunits contain a conserved protein-protein interaction module-the "ZP domain"-that allows them to polymerize upon dissociation of a C-terminal propeptide containing an external hydrophobic patch (EHP). Recently, the first crystal structures of a ZP domain protein, sperm receptor ZP subunit zona pellucida glycoprotein 3 (ZP3), have been reported, giving a glimpse of the structural organization of the ZP at the atomic level and the molecular basis of gamete recognition in vertebrates. The ZP module is divided in two related immunoglobulin-like domains, ZP-N and ZP-C, that contain characteristic disulfide bond patterns and, in the case of ZP-C, also incorporate the EHP. This segment lies at the interface between the two domains, which are connected by a long loop carrying a conserved O-glycan important for binding to sperm in vitro. The structures explain several apparently contradictory observations by reconciling the variable disulfide bond patterns found in different homologues of ZP3 as well as the multiple ZP3 determinants alternatively involved in gamete interaction. These findings have implications for our understanding of ZP subunit biogenesis; egg coat assembly, architecture, and interaction with sperm; structural rearrangements leading to postfertilization hardening of the ZP and the block to sperm binding; and the evolutionary origin of egg coats.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences and Nutrition and Center for Biosciences, Karolinska Institutet, Huddinge, Sweden
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Abstract
Species-specific recognition between egg and sperm, a crucial event that marks the beginning of fertilization in multicellular organisms, mirrors the binding between haploid cells of opposite mating type in unicellular eukaryotes such as yeast. However, as implied by the lack of sequence similarity between sperm-binding regions of invertebrate and vertebrate egg coat proteins, these interactions are thought to rely on completely different molecular entities. Here, we argue that these recognition systems are, in fact, related: despite being separated by 0.6-1 billion years of evolution, functionally essential domains of a mollusc sperm receptor and a yeast mating protein adopt the same 3D fold as egg zona pellucida proteins mediating the binding between gametes in humans.
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Han L, Monné M, Okumura H, Schwend T, Cherry AL, Flot D, Matsuda T, Jovine L. Insights into Egg Coat Assembly and Egg-Sperm Interaction from the X-Ray Structure of Full-Length ZP3. Cell 2010; 143:404-15. [DOI: 10.1016/j.cell.2010.09.041] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 08/11/2010] [Accepted: 08/24/2010] [Indexed: 11/15/2022]
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Bamber L, Harding M, Monné M, Slotboom DJ, Kunji ERS. The yeast mitochondrial ADP/ATP carrier functions as a monomer in mitochondrial membranes. Proc Natl Acad Sci U S A 2007; 104:10830-4. [PMID: 17566106 PMCID: PMC1891095 DOI: 10.1073/pnas.0703969104] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial carriers are believed widely to be dimers both in structure and function. However, the structural fold is a barrel of six transmembrane alpha-helices without an obvious dimerisation interface. Here, we show by negative dominance studies that the yeast mitochondrial ADP/ATP carrier 2 from Saccharomyces cerevisiae (AAC2) is functional as a monomer in the mitochondrial membrane. Adenine nucleotide transport by wild-type AAC2 is inhibited by the sulfhydryl reagent 2-sulfonatoethyl-methanethiosulfonate (MTSES), whereas the activity of a mutant AAC2, devoid of cysteines, is unaffected. Wild-type and cysteine-less AAC2 were coexpressed in different molar ratios in yeast mitochondrial membranes. After addition of MTSES the residual transport activity correlated linearly with the fraction of cysteine-less carrier present in the membranes, and so the two versions functioned independently of each other. Also, the cysteine-less and wild-type carriers were purified separately, mixed in defined ratios and reconstituted into liposomes. Again, the residual transport activity in the presence of MTSES depended linearly on the amount of cysteine-less carrier. Thus, the entire transport cycle for ADP/ATP exchange is carried out by the monomer.
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Affiliation(s)
- Lisa Bamber
- Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, United Kingdom
| | - Marilyn Harding
- Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, United Kingdom
| | - Magnus Monné
- Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, United Kingdom
| | - Dirk-Jan Slotboom
- Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, United Kingdom
| | - Edmund R. S. Kunji
- Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, United Kingdom
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Monné M, Robinson AJ, Boes C, Harbour ME, Fearnley IM, Kunji ERS. The mimivirus genome encodes a mitochondrial carrier that transports dATP and dTTP. J Virol 2007; 81:3181-6. [PMID: 17229695 PMCID: PMC1866048 DOI: 10.1128/jvi.02386-06] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Members of the mitochondrial carrier family have been reported in eukaryotes only, where they transport metabolites and cofactors across the mitochondrial inner membrane to link the metabolic pathways of the cytosol and the matrix. The genome of the giant virus Mimiviridae mimivirus encodes a member of the mitochondrial carrier family of transport proteins. This viral protein has been expressed in Lactococcus lactis and is shown to transport dATP and dTTP. As the 1.2-Mb double-stranded DNA mimivirus genome is rich in A and T residues, we speculate that the virus is using this protein to target the host mitochondria as a source of deoxynucleotides for its replication.
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Affiliation(s)
- Magnus Monné
- Dunn Human Nutrition Unit, Medical Research Council, Hills Road, Cambridge CB2 2XY, United Kingdom
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38
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Abstract
Oocytes from virtually all organisms are surrounded by at least one coat. This specialized extracellular matrix, called the zona pellucida (ZP) in mammals and the vitelline envelope (VE) in nonmammals, has a structural function and plays essential roles in oogenesis, fertilization, and early development. During the last 15 years, compelling evidence has accumulated that all ZP/VE subunits polymerize using a conserved sequence, the ZP domain, so that the basic structural features of egg coat matrices have been maintained through evolution. Moreover, ZP domains have been identified in many other polymeric extracellular proteins from eukaryotes. This review compares the ultrastructure and molecular composition of egg coats from mollusc to human, suggests a common mechanism for assembly of ZP/VE proteins, and discusses alternative models of how these could be arranged within filaments.
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Affiliation(s)
- Magnus Monné
- Karolinska Institutet, Department of Biosciences and Nutrition, Center for Structural Biochemistry, Huddinge, Sweden
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Kunji ERS, Chan KW, Slotboom DJ, Floyd S, O'Connor R, Monné M. Eukaryotic membrane protein overproduction in Lactococcus lactis. Curr Opin Biotechnol 2005; 16:546-51. [PMID: 16143505 DOI: 10.1016/j.copbio.2005.08.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Revised: 06/30/2005] [Accepted: 08/25/2005] [Indexed: 11/16/2022]
Abstract
Eukaryotic membrane proteins play many vital roles in the cell and are important drug targets. Approximately 25% of all genes identified in the genome are known to encode membrane proteins, but the vast majority have no assigned function. Although the generation of structures of soluble proteins has entered the high-throughput stage, for eukaryotic membrane proteins only a dozen high-resolution structures have been obtained so far. One major bottleneck for the functional and structural characterisation of membrane proteins is the overproduction of biologically active material. Recent advances in the development of the Lactococcus lactis expression system have opened the way for the high-throughput functional expression of eukaryotic membrane proteins.
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Affiliation(s)
- Edmund R S Kunji
- The Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Wellcome Trust/MRC Building, Cambridge CB2 2XY, United Kingdom.
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Villarejo A, Burén S, Larsson S, Déjardin A, Monné M, Rudhe C, Karlsson J, Jansson S, Lerouge P, Rolland N, von Heijne G, Grebe M, Bako L, Samuelsson G. Evidence for a protein transported through the secretory pathway en route to the higher plant chloroplast. Nat Cell Biol 2005; 7:1224-31. [PMID: 16284624 DOI: 10.1038/ncb1330] [Citation(s) in RCA: 219] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Accepted: 09/29/2005] [Indexed: 11/08/2022]
Abstract
In contrast to animal and fungal cells, green plant cells contain one or multiple chloroplasts, the organelle(s) in which photosynthetic reactions take place. Chloroplasts are believed to have originated from an endosymbiotic event and contain DNA that codes for some of their proteins. Most chloroplast proteins are encoded by the nuclear genome and imported with the help of sorting signals that are intrinsic parts of the polypeptides. Here, we show that a chloroplast-located protein in higher plants takes an alternative route through the secretory pathway, and becomes N-glycosylated before entering the chloroplast.
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Affiliation(s)
- Arsenio Villarejo
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, S-90187 Umeå, Sweden
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41
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Abstract
The overproduction of eukaryotic membrane proteins is a major impediment in their structural and functional characterization. Here we have used the nisin-inducible expression system of Lactococcus lactis for the overproduction of 11 mitochondrial transport proteins from yeast. They were expressed at high levels in a functional state in the cytoplasmic membrane. The results also show that the level of expression is influenced by the N-terminal regions of the transporters. Expression levels were improved >10-fold either by replacing or truncating these regions or by adding lactococcal signal peptides. The observed expression levels are now compatible with a realistic exploration of crystallization conditions. The lactococcal expression system may be used for the high-throughput functional characterization of eukaryotic membrane proteins and structural genomics.
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Affiliation(s)
- Magnus Monné
- The Medical Research Council, Dunn Human Nutrition Unit, Hills Road, Wellcome Trust/MRC Building, Cambridge CB2 2XY, UK
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Ding B, Kull B, Liu Z, Mottagui-Tabar S, Thonberg H, Gu HF, Brookes AJ, Grundemar L, Karlsson C, Hamsten A, Arner P, Ostenson CG, Efendic S, Monné M, von Heijne G, Eriksson P, Wahlestedt C. Human neuropeptide Y signal peptide gain-of-function polymorphism is associated with increased body mass index: possible mode of function. ACTA ACUST UNITED AC 2005; 127:45-53. [PMID: 15680469 DOI: 10.1016/j.regpep.2004.10.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2004] [Accepted: 10/21/2004] [Indexed: 11/28/2022]
Abstract
Neuropeptide Y (NPY) has been implicated in the control of food intake and energy balance based on many observations in animals. We have studied single nucleotide polymorphisms (SNPs) within the regulatory and coding sequences of the human NPY gene. One variant (1128 T>C), which causes an amino acid change from leucine to proline at codon 7 in the signal peptide of NPY, was associated with increased body mass index (BMI) in two separate Swedish populations of normal and overweight individuals. In vitro transcription and translation studies indicated the unlikelihood that this signal peptide variation affects the site of cleavage and targeting or uptake of NPY into the endoplasmic reticulum (ER). However, the mutant, and to a lesser extent the wild-type, signal peptide by themselves markedly potentiated NPY-induced food intake, as well as hypothalamic NPY receptor signaling. Our findings in humans strongly indicate that the NPY signaling system is implicated in body weight regulation and suggest a new and unexpected functional role of a signal peptide.
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Affiliation(s)
- Bo Ding
- Center for Genomics and Bioinformatics, Karolinska Institutet, Stockholm SE-171 77, Sweden.
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Abstract
To better define the mechanism of membrane protein insertion into the membrane of the endoplasmic reticulum, we measured the kinetics of translocation across microsomal membranes of the N-terminal lumenal tail and the lumenal domain following the second transmembrane segment (TM2) in the multispanning mouse protein Cig30. In the wild-type protein, the N-terminal tail translocates across the membrane before the downstream lumenal domain. Addition of positively charged residues to the N-terminal tail dramatically slows down its translocation and allows the downstream lumenal domain to translocate at the same time as or even before the N-tail. When TM2 is deleted, or when the loop between TM1 and TM2 is lengthened, addition of positively charged residues to the N-terminal tail causes TM1 to adopt an orientation with its N-terminal end in the cytoplasm. We suggest that the topology of the TM1-TM2 region of Cig30 depends on a competition between TM1 and TM2 such that the transmembrane segment that inserts first into the ER membrane determines the final topology.
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Affiliation(s)
- Magnus Monné
- Department of Biochemistry and Biophysics, Stockholm University, Sweden
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Abstract
Hepatitis C virus (HCV) belongs to the Hepacivirus genus in the Flaviviridae family. Among the least known viral proteins in this family is the nonstructural protein NS4B, which has been suggested to be a part of the replication complex. Hydrophobicity plots indicate a common profile among the NS4B proteins from different members of the Flaviviridae family, suggesting a common function. In order to gain a deeper understanding of the nature of HCV NS4B, we have determined localization and topology of this protein by using recombinant HCV NS4B constructs. The protein localized to the endoplasmic reticulum (ER), but also induced a pattern of cytoplasmic foci positive for markers of the ER. Computer predictions of the membrane topology of NS4B suggested that it has four transmembrane segments. The N and C termini were anticipated to be localized in the cytoplasm, because they are processed by the cytoplasmic NS3 protein. By introducing glycosylation sites at various positions in HCV NS4B, we show that the C terminus is cytoplasmic and the loop around residue 161 is lumenal as predicted. Surprisingly, the N-terminal tail was translocated into the lumen in a considerable fraction of the NS4B molecules, most likely by a posttranslational process. Interestingly, NS4B proteins of the yellow fever and dengue viruses also have their N termini located in the ER lumen due to an N-terminal signal peptide not found in NS4B of HCV. A shared topology achieved in two different ways supports the notion of a common function for NS4B in FLAVIVIRIDAE:
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Affiliation(s)
- Marika Lundin
- Karolinska Institutet, Department of Medicine at Center of Molecular Medicine, Karolinska Hospital, S-171 76 Stockholm, Sweden
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Hessa T, Monné M, von Heijne G. Stop-transfer efficiency of marginally hydrophobic segments depends on the length of the carboxy-terminal tail. EMBO Rep 2003; 4:178-83. [PMID: 12612608 PMCID: PMC1315826 DOI: 10.1038/sj.embor.embor728] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2002] [Revised: 11/07/2002] [Accepted: 11/20/2002] [Indexed: 11/09/2022] Open
Abstract
Hydrophobic stop-transfer sequences generally serve to halt the translocation of polypeptide chains across the endoplasmic reticulum membrane and become integrated as transmembrane alpha-helices. Using engineered glycosylation sites as topology reporters, we show that the length of the nascent chain between a hydrophobic segment and the carboxy terminus of the protein can affect stop-transfer efficiency. We also show that glycosylation sites located close to a protein's C terminus are modified in two distinct kinetic phases, one fast and one slow. Our findings suggest that membrane integration of a hydrophobic segment is not simply a question of thermodynamic equilibrium, but can be influenced by details of the translocation mechanism.
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Affiliation(s)
- Tara Hessa
- Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Magnus Monné
- Present address: MRC-Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, UK
| | - Gunnar von Heijne
- Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden
- Tel: +46 8 16 25 90; Fax: +46 8 15 36 79;
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Vilar M, Saurí A, Monné M, Marcos JF, von Heijne G, Pérez-Payá E, Mingarro I. Insertion and topology of a plant viral movement protein in the endoplasmic reticulum membrane. J Biol Chem 2002; 277:23447-52. [PMID: 11976343 DOI: 10.1074/jbc.m202935200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Virus-encoded movement proteins (MPs) mediate cell-to-cell spread of viral RNA through plant membranous intercellular connections, the plasmodesmata. The molecular pathway by which MPs interact with viral genomes and target plasmodesmata channels is largely unknown. The 9-kDa MP from carnation mottle carmovirus (CarMV) contains two potential transmembrane domains. To explore the possibility that this protein is in fact an intrinsic membrane protein, we have investigated its insertion into the endoplasmic reticulum membrane. By using in vitro translation in the presence of dog pancreas microsomes, we demonstrate that CarMV p9 inserts into the endoplasmic reticulum without the aid of any additional viral or plant host components. We further show that the membrane topology of CarMV p9 is N(cyt)-C(cyt) (N and C termini of the protein facing the cytoplasm) by in vitro translation of a series of truncated and full-length constructs with engineered glycosylation sites. Based on these results, we propose a topological model in which CarMV p9 is anchored in the membrane with its N- and C-terminal tail segments interacting with its soluble, RNA-bound partner CarMV p7, to accomplish the viral cell-to-cell movement function.
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Affiliation(s)
- Marçal Vilar
- Departament de Bioquímica i Biologia Molecular, Universitat de València, E-46 100 Burjassot, Spain
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Hermansson M, Monné M, von Heijne G. Formation of helical hairpins during membrane protein integration into the endoplasmic reticulum membrane. Role of the N and C-terminal flanking regions. J Mol Biol 2001; 313:1171-9. [PMID: 11700072 DOI: 10.1006/jmbi.2001.5108] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The helical hairpin, two closely spaced transmembrane helices separated by a short turn, is a common structural element in integral membrane proteins. Previous studies on the sequence determinants of helical hairpin formation have focussed on the role of polar and charged residues placed centrally in a long stretch of hydrophobic residues, and have yielded a "propensity scale" for the relative efficiency with which different residues promote the formation of helical hairpins. In this study, we shift our attention to the role of charged residues flanking the hydrophobic stretch. Clusters of charged residues are known to hinder membrane translocation, and thus flanking charged residues may conceivably force a long hydrophobic segment to form a helical hairpin even if there are no or only weakly turn-promoting residues in the hydrophobic stretch. We indeed find that Lys and, more surprisingly, Asp residues strongly affect helical hairpin formation when placed next to a poly-Leu-based transmembrane segment. We also find that a cluster of four consecutive Lys residues can affect the efficiency of helical hairpin formation even when placed approximately 30 residues downstream of the hydrophobic stretch. These observations have interesting implications for the way we picture membrane protein topogenesis within the context of the endoplasmic reticulum (ER) translocon.
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Affiliation(s)
- M Hermansson
- Department of Biochemistry and Biophysics, Stockholm University, S-106 91 Stockholm, Sweden
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Abstract
We have studied the effects of 'hydrophobic mismatch' between a poly-Leu transmembrane helix (TMH) and the ER membrane using a glycosylation mapping approach. The simplest interpretation of our results is that the lumenal end of the TMH is located deeper in the membrane for both short (negative mismatch) and long (positive mismatch) TMHs than for poly-Leu segments of intermediate length. We further find that the position-specific effect of Lys residues on the location of short TMHs in the membrane varies with an apparent helical periodicity when the Lys residue is moved along the poly-Leu stretch. We discuss these findings in the context of models for peptide-lipid interactions during hydrophobic mismatch.
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Affiliation(s)
- M Monné
- Department of Biochemistry and Biophysics, Stockholm University, S-106 91, Stockholm, Sweden
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Monné M, Nilsson I, Elofsson A, von Heijne G. Turns in transmembrane helices: determination of the minimal length of a "helical hairpin" and derivation of a fine-grained turn propensity scale. J Mol Biol 1999; 293:807-14. [PMID: 10543969 DOI: 10.1006/jmbi.1999.3183] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have recently reported a first experimental turn propensity scale for transmembrane helices. This scale was derived from measurements of how efficiently a given residue placed in the middle of a 40 residue poly(Leu) stretch induces the formation of a "helical hairpin" with two rather than one transmembrane segment. We have now extended these studies, and have determined the minimum length of a poly(Leu) stretch compatible with the formation of a helical hairpin. We have also derived a more fine-grained turn propensity scale by (i) introducing each of the 20 amino acid residues into the middle of the shortest poly(Leu) stretch compatible with helical hairpin formation, and (ii) introducing pairs of residues in the middle of the 40 residue poly(Leu) stretch. The new turn propensities are consistent with the amino acid frequencies found in short hairpin loops in membrane proteins of known 3D structure.
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Affiliation(s)
- M Monné
- Department of Biochemistry, Stockholm University, Stockholm, S-106 91, Sweden
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Monné M, Gafvelin G, Nilsson R, von Heijne G. N-tail translocation in a eukaryotic polytopic membrane protein: synergy between neighboring transmembrane segments. Eur J Biochem 1999; 263:264-9. [PMID: 10429212 DOI: 10.1046/j.1432-1327.1999.00498.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have used the natural N-glycosylation site in the N-tail of cig30, a eukaryotic polytopic membrane protein, as a marker for N-tail translocation across the microsomal membrane. Analysis of C-terminally truncated cig30 constructs reveals that the first transmembrane segment is sufficient for translocation of the wild-type N-tail; in contrast, in a mutant with four arginines introduced into the N-tail the second transmembrane segment is also required for efficient N-tail translocation. Our observations imply a non-sequential assembly mechanism in which the ultimate location of the N-tail relative to the membrane may depend on more than one transmembrane segment.
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Affiliation(s)
- M Monné
- Department of Biochemistry, Stockholm University, Stockholm, Sweden
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