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Bruna RE, Kendra CG, Pontes MH. An intracellular phosphorus-starvation signal activates the PhoB/PhoR two-component system in Salmonella enterica. mBio 2024; 15:e0164224. [PMID: 39152718 PMCID: PMC11389368 DOI: 10.1128/mbio.01642-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Accepted: 07/01/2024] [Indexed: 08/19/2024] Open
Abstract
Bacteria acquire P primarily as inorganic orthophosphate (Pi, PO43-). Once internalized, Pi is rapidly assimilated into biomass during the synthesis of ATP. Because Pi is essential, but excessive ATP is toxic, the acquisition of environmental Pi is tightly regulated. In the bacterium Salmonella enterica (Salmonella), growth in Pi-limiting environments activates the membrane sensor histidine kinase PhoR, leading to the phosphorylation of its cognate transcriptional regulator PhoB and subsequent transcription of genes involved in adaptations to low Pi. Pi limitation promotes PhoR kinase activity by altering the conformation of a membrane signaling complex comprised of PhoR, the multicomponent Pi transporter system PstSACB and the regulatory protein PhoU. However, the identity of the Pi-starvation signal and how it controls PhoR activity remain unknown. Here, we identify conditions where the PhoB and PhoR signal transduction proteins can be maintained in an inactive state when Salmonella is grown in media lacking Pi. Our results demonstrate that PhoB/PhoR is activated by an intracellular P-insufficiency signal.IMPORTANCEIn enteric bacteria, the transcriptional response to phosphorus (P) starvation is controlled by a specialized signal transduction system comprised of a membrane-bound, multicomponent signal sensor, and a cytoplasmic transcriptional factor. Whereas this system has been primarily studied in the context of phosphate (Pi) starvation, it is currently unknown how this stress initiates signal transduction. In the current study, we establish that this signaling system is regulated by a cytoplasmic signal arising from insufficient P. We demonstrate that rather than responding to extracellular conditions, cells couple the activation of their P starvation response to the availability of cytoplasmic P. This regulatory logic may enable cells to prevent toxicity resulting from excessive Pi acquisition and hinder the onset of a P starvation response when their metabolic demands are being met through the consumption of P sources other than Pi.
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Affiliation(s)
- Roberto E. Bruna
- Department of Pathology and Laboratory Medicine, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
- The One Health Microbiome Center, Huck Institute of the Life Sciences, Pennsylvania State University, Camp Hill, Pennsylvania, USA
| | - Christopher G. Kendra
- Department of Pathology and Laboratory Medicine, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
- The One Health Microbiome Center, Huck Institute of the Life Sciences, Pennsylvania State University, Camp Hill, Pennsylvania, USA
| | - Mauricio H. Pontes
- Department of Pathology and Laboratory Medicine, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
- The One Health Microbiome Center, Huck Institute of the Life Sciences, Pennsylvania State University, Camp Hill, Pennsylvania, USA
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2
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Bruna RE, Kendra CG, Pontes MH. An intracellular phosphorus-starvation signal activates the PhoB/PhoR two-component system in Salmonella enterica. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.23.533958. [PMID: 36993483 PMCID: PMC10055408 DOI: 10.1101/2023.03.23.533958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Bacteria acquire P primarily as inorganic orthophosphate (Pi, PO43-). Once internalized, Pi is rapidly assimilated into biomass during the synthesis of ATP. Because Pi is essential, but excessive ATP is toxic, the acquisition of environmental Pi is tightly regulated. In the bacterium Salmonella enterica (Salmonella), growth in Pi-limiting environments activates the membrane sensor histidine kinase PhoR, leading to the phosphorylation of its cognate transcriptional regulator PhoB and subsequent transcription of genes involved in adaptations to low Pi. Pi limitation is thought to promote PhoR kinase activity by altering the conformation of a membrane signaling complex comprised by PhoR, the multicomponent Pi transporter system PstSACB and the regulatory protein PhoU. However, the identity of the low Pi signal and how it controls PhoR activity remain unknown. Here we characterize the PhoB-dependent and independent transcriptional changes elicited by Salmonella in response to P starvation, and identify PhoB-independent genes that are required for the utilization of several organic-P sources. We use this knowledge to identify the cellular compartment where the PhoR signaling complex senses the Pi-limiting signal. We demonstrate that the PhoB and PhoR signal transduction proteins can be maintained in an inactive state even when Salmonella is grown in media lacking Pi. Our results establish that PhoR activity is controlled by an intracellular signal resulting from P insufficiency.
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Affiliation(s)
- Roberto E. Bruna
- Department of Pathology and Laboratory Medicine, Pennsylvania State College of Medicine, Hershey, PA 17033, United States of America
| | - Christopher G. Kendra
- Department of Pathology and Laboratory Medicine, Pennsylvania State College of Medicine, Hershey, PA 17033, United States of America
| | - Mauricio H. Pontes
- Department of Pathology and Laboratory Medicine, Pennsylvania State College of Medicine, Hershey, PA 17033, United States of America
- Department of Microbiology and Immunology, Pennsylvania State College of Medicine, Hershey, PA 17033, United States of America
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3
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Carvalho-de-Araújo AD, Carvalho-Kelly LF, Dick CF, Meyer-Fernandes JR. Inorganic phosphate transporter in Giardia duodenalis and its possible role in ATP synthesis. Mol Biochem Parasitol 2022; 251:111504. [PMID: 35843419 DOI: 10.1016/j.molbiopara.2022.111504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 06/14/2022] [Accepted: 07/13/2022] [Indexed: 10/17/2022]
Abstract
Giardia duodenalis is a flagellated protozoan that inhabits vertebrate host intestines, causing the disease known as giardiasis. Similar to other parasites, G. duodenalis must take advantage of environmental resources to survive, such as inorganic phosphate (Pi) availability. Pi is an anionic molecule and an essential nutrient for all organisms because it participates in the biosynthesis of biomolecules, energy storage, and cellular structure formation. The first step in Pi metabolism is its uptake through specific transporters on the plasma membrane. We identified a symporter H+:Pi-type ORF sequence in the G. duodenalis genome (GenBank ID: GL50803_5164), named GdPho84, which is homologous to Saccharomyces cerevisiae PHO84. In trophozoites, Pi transport was linear for up to 15 min, and the cell density was 3 × 107 cells/ml. Physiological variations in pH (6.4-8.0) did not influence Pi uptake. This Pi transporter had a high affinity, with K0.5 = 67.7 ± 7.1 µM Pi. SCH28080 (inhibitor of H+, K+-ATPase), bafilomycin A1 (inhibitor of vacuolar H+-ATPase), and FCCP (H+ ionophore) were able to inhibit Pi transport, indicating that an H+ gradient in the cell powered uphill Pi movement. PAA, an H+-dependent Pi transport inhibitor, reduced cell proliferation, Pi transport activity, and GdPHO48 mRNA levels. Pi starvation stimulated membrane potential-sensitive Pi uptake coupled to H+ fluxes, increased GdPho84 expression, and reduced intracellular ATP levels. These events indicate that these cells had an increased capacity to internalize Pi as a compensatory mechanism compared to cells maintained in control medium conditions. Internalized Pi can be used in glycolytic metabolism once iodoacetamide (GAPDH inhibitor) inhibits Pi influx. Together, these results reinforce the hypothesis that Pi is a crucial nutrient for G. duodenalis energy metabolism.
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Affiliation(s)
| | - Luiz Fernando Carvalho-Kelly
- Leopoldo de Meis Institute of Medical Biochemistry, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Claudia F Dick
- Leopoldo de Meis Institute of Medical Biochemistry, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
| | - José Roberto Meyer-Fernandes
- Leopoldo de Meis Institute of Medical Biochemistry, Federal University of Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
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4
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Ribeiro‐Filho N, Ayed C, Akepach P. The buffering capacity of single amino acids in brewing wort. Int J Food Sci Technol 2022. [DOI: 10.1111/ijfs.15924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Normando Ribeiro‐Filho
- DSER/Centre for Agrarian Science Campus II Federal University of Paraiba Areia Paraiba Brazil
| | - Charfedinne Ayed
- Division of Food, Nutrition and Dietetics, School of Biosciences University of Nottingham Loughborough Leicestershire UK
| | - Patchaniya Akepach
- Department of Thai and International Culinary Art, International School of Tourism Suratthani Rajabhat University Tambon Bo Put, Amphoe Ko Samui Chang Wat Surat Thani 84320 Thailand
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5
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Austin S, Mayer A. Phosphate Homeostasis - A Vital Metabolic Equilibrium Maintained Through the INPHORS Signaling Pathway. Front Microbiol 2020; 11:1367. [PMID: 32765429 PMCID: PMC7381174 DOI: 10.3389/fmicb.2020.01367] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/27/2020] [Indexed: 12/12/2022] Open
Abstract
Cells face major changes in demand for and supply of inorganic phosphate (Pi). Pi is often a limiting nutrient in the environment, particularly for plants and microorganisms. At the same time, the need for phosphate varies, establishing conflicts of goals. Cells experience strong peaks of Pi demand, e.g., during the S-phase, when DNA, a highly abundant and phosphate-rich compound, is duplicated. While cells must satisfy these Pi demands, they must safeguard themselves against an excess of Pi in the cytosol. This is necessary because Pi is a product of all nucleotide-hydrolyzing reactions. An accumulation of Pi shifts the equilibria of these reactions and reduces the free energy that they can provide to drive endergonic metabolic reactions. Thus, while Pi starvation may simply retard growth and division, an elevated cytosolic Pi concentration is potentially dangerous for cells because it might stall metabolism. Accordingly, the consequences of perturbed cellular Pi homeostasis are severe. In eukaryotes, they range from lethality in microorganisms such as yeast (Sethuraman et al., 2001; Hürlimann, 2009), severe growth retardation and dwarfism in plants (Puga et al., 2014; Liu et al., 2015; Wild et al., 2016) to neurodegeneration or renal Fanconi syndrome in humans (Legati et al., 2015; Ansermet et al., 2017). Intracellular Pi homeostasis is thus not only a fundamental topic of cell biology but also of growing interest for medicine and agriculture.
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Affiliation(s)
- Sisley Austin
- Département de Biochimie, Université de Lausanne, Lausanne, Switzerland
| | - Andreas Mayer
- Département de Biochimie, Université de Lausanne, Lausanne, Switzerland
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6
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Fabiańska I, Bucher M, Häusler RE. Intracellular phosphate homeostasis - A short way from metabolism to signaling. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 286:57-67. [PMID: 31300142 DOI: 10.1016/j.plantsci.2019.05.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/14/2019] [Accepted: 05/22/2019] [Indexed: 05/21/2023]
Abstract
Phosphorus in plant cells occurs in inorganic form as both ortho- and pyrophosphate or bound to organic compounds, like e.g., nucleotides, phosphorylated metabolites, phospholipids, phosphorylated proteins, or phytate as P storage in the vacuoles of seeds. Individual compartments of the cell are surrounded by membranes that are selective barriers to avoid uncontrolled solute exchange. A controlled exchange of phosphate or phosphorylated metabolites is accomplished by specific phosphate transporters (PHTs) and the plastidial phosphate translocator family (PTs) of the inner envelope membrane. Plastids, in particular chloroplasts, are the site of various anabolic sequences of enzyme-catalyzed reactions. Apart from their role in metabolism PHTs and PTs are presumed to be also involved in communication between organelles and plant organs. Here we will focus on the integration of phosphate transport and homeostasis in signaling processes. Recent developments in this field will be critically assessed and potential future developments discussed. In particular, the occurrence of various plastid types in one organ (i.e. the leaf) with different functions with respect to metabolism or sensing, as has been documented recently following a tissue-specific proteomics approach (Beltran et al., 2018), will shed new light on functional aspects of phosphate homeostasis.
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Affiliation(s)
- Izabela Fabiańska
- Botanical Institute, Cologne Biocenter, University of Cologne, 50674 Cologne, Germany
| | - Marcel Bucher
- Botanical Institute, Cologne Biocenter, University of Cologne, 50674 Cologne, Germany; Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, 50674 Cologne, Germany
| | - Rainer E Häusler
- Botanical Institute, Cologne Biocenter, University of Cologne, 50674 Cologne, Germany.
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7
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Karginov AV, Fokina AV, Kang HA, Kalebina TS, Sabirzyanova TA, Ter-Avanesyan MD, Agaphonov MO. Dissection of differential vanadate sensitivity in two Ogataea species links protein glycosylation and phosphate transport regulation. Sci Rep 2018; 8:16428. [PMID: 30401924 PMCID: PMC6219546 DOI: 10.1038/s41598-018-34888-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 10/24/2018] [Indexed: 11/08/2022] Open
Abstract
The closely related yeasts Ogataea polymorpha and O. parapolymorpha differ drastically from each other by sensitivity to the toxic phosphate analog vanadate. Search for genes underlying this difference revealed two genes, one designated as ABV1 (Alcian Blue staining, Vanadate resistance), which encodes a homologue of Saccharomyces cerevisiae Mnn4 responsible for attachment of mannosylphosphate to glycoside chains of secretory proteins, and the other designated as its S. cerevisiae homologue PHO87, encoding the plasma membrane low affinity phosphate sensor/transporter. The effect of Pho87 on vanadate resistance was bidirectional, since it decreased the resistance on phosphate-depleted medium, but was required for pronounced protection against vanadate by external phosphate. This highlights the dual function of this protein as a low affinity phosphate transporter and an external phosphate sensor. Involvement of Pho87 in phosphate sensing was confirmed by its effects on regulation of the promoter of the PHO84 gene, encoding a high affinity phosphate transporter. The effect of Abv1 was also complex, since it influenced Pho87 level and enhanced repression of the PHO84 promoter via a Pho87-independent pathway. Role of the identified genes in the difference in vanadate resistance between O. polymorpha and O. parapolymorpha is discussed.
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Affiliation(s)
- Azamat V Karginov
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, Moscow, Russian Federation
| | - Anastasia V Fokina
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, Moscow, Russian Federation
| | - Hyun Ah Kang
- Department of Life Science, Chung-Ang University, Seoul, Republic of Korea
| | - Tatyana S Kalebina
- Department of Molecular Biology, Biological Faculty, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Tatyana A Sabirzyanova
- Department of Molecular Biology, Biological Faculty, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Michael D Ter-Avanesyan
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, Moscow, Russian Federation
| | - Michael O Agaphonov
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, Moscow, Russian Federation.
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8
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Evolutionary conservation of a core fungal phosphate homeostasis pathway coupled to development in Blastocladiella emersonii. Fungal Genet Biol 2018; 115:20-32. [PMID: 29627365 DOI: 10.1016/j.fgb.2018.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 01/08/2023]
Abstract
The model yeast Saccharomyces cerevisiae elicits a transcriptional response to phosphate (Pi) depletion. To determine the origins of the phosphate response (PHO) system, we bioinformatically identified putative PHO components in the predicted proteomes of diverse fungi. Our results suggest that the PHO system is ancient; however, components have been expanded or lost in different fungal lineages. To show that a similar physiological response is present in deeply-diverging fungi we examined the transcriptional and physiological response of PHO genes to Pi depletion in the blastocladiomycete Blastocladiella emersonii. Our physiological experiments indicate that B. emersonii relies solely on high-affinity Na+-independent Pho84-like transporters. In response to Pi depletion, BePho84 paralogues were 4-8-fold transcriptionally upregulated, whereas several other PHO homologues like phosphatases and vacuolar transporter chaperone (VTC) complex components show 2-3-fold transcriptional upregulation. Since Pi has been shown to be important during the development of B. emersonii, we sought to determine if PHO genes are differentially regulated at different lifecycle stages. We demonstrate that a similar set of PHO transporters and phosphatases are upregulated at key points during B. emersonii development. Surprisingly, some genes upregulated during Pi depletion, including VTC components, are repressed at these key stages of development indicating that PHO genes are regulated by different pathways in different developmental and environmental situations. Overall, our findings indicate that a complex PHO network existed in the ancient branches of the fungi, persists in diverse extant fungi, and that this ancient network is likely to be involved in development and cell cycle regulation.
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9
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Bru S, Samper-Martín B, Quandt E, Hernández-Ortega S, Martínez-Laínez JM, Garí E, Rafel M, Torres-Torronteras J, Martí R, Ribeiro MPC, Jiménez J, Clotet J. Polyphosphate is a key factor for cell survival after DNA damage in eukaryotic cells. DNA Repair (Amst) 2017; 57:171-178. [PMID: 28822913 DOI: 10.1016/j.dnarep.2017.08.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 07/30/2017] [Accepted: 08/04/2017] [Indexed: 12/11/2022]
Abstract
Cells require extra amounts of dNTPs to repair DNA after damage. Polyphosphate (polyP) is an evolutionary conserved linear polymer of up to several hundred inorganic phosphate (Pi) residues that is involved in many functions, including Pi storage. In the present article, we report on findings demonstrating that polyP functions as a source of Pi when required to sustain the dNTP increment essential for DNA repair after damage. We show that mutant yeast cells without polyP produce less dNTPs upon DNA damage and that their survival is compromised. In contrast, when polyP levels are ectopically increased, yeast cells become more resistant to DNA damage. More importantly, we show that when polyP is reduced in HEK293 mammalian cell line cells and in human dermal primary fibroblasts (HDFa), these cells become more sensitive to DNA damage, suggesting that the protective role of polyP against DNA damage is evolutionary conserved. In conclusion, we present polyP as a molecule involved in resistance to DNA damage and suggest that polyP may be a putative target for new approaches in cancer treatment or prevention.
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Affiliation(s)
- Samuel Bru
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Bàrbara Samper-Martín
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Eva Quandt
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Sara Hernández-Ortega
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Joan M Martínez-Laínez
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Eloi Garí
- Institut de Recerca Biomèdica de Lleida (IRBLleida), Departament de Ciències Mèdiques Bàsiques, Facultat de Medicina, Universitat de Lleida, Lleida, Spain
| | - Marta Rafel
- Institut de Recerca Biomèdica de Lleida (IRBLleida), Departament de Ciències Mèdiques Bàsiques, Facultat de Medicina, Universitat de Lleida, Lleida, Spain
| | - Javier Torres-Torronteras
- Research Group on Neuromuscular and Mitochondrial Disorders, Vall d'Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Spain; Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Ramón Martí
- Research Group on Neuromuscular and Mitochondrial Disorders, Vall d'Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Spain; Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Mariana P C Ribeiro
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Javier Jiménez
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain.
| | - Josep Clotet
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain.
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10
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Russo-Abrahão T, Koeller CM, Steinmann ME, Silva-Rito S, Marins-Lucena T, Alves-Bezerra M, Lima-Giarola NL, de-Paula IF, Gonzalez-Salgado A, Sigel E, Bütikofer P, Gondim KC, Heise N, Meyer-Fernandes JR. H +-dependent inorganic phosphate uptake in Trypanosoma brucei is influenced by myo-inositol transporter. J Bioenerg Biomembr 2017; 49:183-194. [PMID: 28185085 DOI: 10.1007/s10863-017-9695-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 01/22/2017] [Indexed: 10/20/2022]
Abstract
Trypanosoma brucei is an extracellular protozoan parasite that causes human African trypanosomiasis or "sleeping sickness". During the different phases of its life cycle, T. brucei depends on exogenous inorganic phosphate (Pi), but little is known about the transport of Pi in this organism. In the present study, we showed that the transport of 32Pi across the plasma membrane follows Michaelis-Menten kinetics and is modulated by pH variation, with higher activity at acidic pH. Bloodstream forms presented lower Pi transport in comparison to procyclic forms, that displayed an apparent K0.5 = 0.093 ± 0.008 mM. Additionally, FCCP (H+-ionophore), valinomycin (K+-ionophore) and SCH28080 (H+, K+-ATPase inhibitor) inhibited the Pi transport. Gene Tb11.02.3020, previously described to encode the parasite H+:myo-inositol transporter (TbHMIT), was hypothesized to be potentially involved in the H+:Pi cotransport because of its similarity with the Pho84 transporter described in S. cerevisiae and other trypanosomatids. Indeed, the RNAi mediated knockdown remarkably reduced TbHMIT gene expression, compromised cell growth and decreased Pi transport by half. In addition, Pi transport was inhibited when parasites were incubated in the presence of concentrations of myo-inositol that are above 300 μM. However, when expressed in Xenopus laevis oocytes, two-electrode voltage clamp experiments provided direct electrophysiological evidence that the protein encoded by TbHMIT is definitely a myo-inositol transporter that may be only marginally affected by the presence of Pi. These results confirmed the presence of a Pi carrier in T. brucei, similar to the H+-dependent inorganic phosphate system described in S. cerevisiae and other trypanosomatids. This transport system contributes to the acquisition of Pi and may be involved in the growth and survival of procyclic forms. In summary, this work presents the first description of a Pi transport system in T. brucei.
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Affiliation(s)
- Thais Russo-Abrahão
- Instituto de Microbiologia Professor Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.,Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - Carolina Macedo Koeller
- Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil
| | - Michael E Steinmann
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Stephanie Silva-Rito
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - Thaissa Marins-Lucena
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - Michele Alves-Bezerra
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - Naira Ligia Lima-Giarola
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - Iron Francisco de-Paula
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - Amaia Gonzalez-Salgado
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Erwin Sigel
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Katia Calp Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - Norton Heise
- Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.
| | - José Roberto Meyer-Fernandes
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil. .,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil.
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11
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Vieira-Bernardo R, Gomes-Vieira AL, Carvalho-Kelly LF, Russo-Abrahão T, Meyer-Fernandes JR. The biochemical characterization of two phosphate transport systems in Phytomonas serpens. Exp Parasitol 2016; 173:1-8. [PMID: 27956087 DOI: 10.1016/j.exppara.2016.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 11/01/2016] [Accepted: 12/08/2016] [Indexed: 10/20/2022]
Abstract
Inorganic phosphate (Pi) is an essential nutrient for all organisms because it is required for a variety of biochemical processes, such as signal transduction and the synthesis of phosphate-containing biomolecules. Assays of 32Pi uptake performed in the absence or in the presence of Na+ indicated the existence of a Na+-dependent and a Na+-independent Pi transporter in Phytomonas serpens. Phylogenetic analysis of two hypothetical protein sequences of Phytomonas (EM1) showed similarities to the high-affinity Pi transporters of Saccharomyces cerevisiae: Pho84, a Na+-independent Pi transporter, and Pho89, a Na+-dependent Pi transporter. Plasma membrane depolarization by FCCP, an H+ ionophore, strongly decreased Pi uptake via both Na+-independent and Na+-dependent carriers, indicating that a membrane potential is essential for Pi influx. In addition, the furosemide-sensitive Na+-pump activity in the cells grown in low Pi conditions was found to be higher than the activity detected in the plasma membrane of cells cultivated at high Pi concentration, suggesting that the up-regulation of the Na+-ATPase pump could be related to the increase of Pi uptake by the Pho89p Na+:Pi symporter. Here we characterize for the first time two inorganic phosphate transporters powered by Na+ and H+ gradients and activated by low Pi availability in the phytopathogen P. serpens.
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Affiliation(s)
- Rodrigo Vieira-Bernardo
- Laboratório de Bioquímica Celular, Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - André Luiz Gomes-Vieira
- Instituto de Ciências Exatas, Departamento de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil
| | - Luiz Fernando Carvalho-Kelly
- Laboratório de Bioquímica Celular, Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Thais Russo-Abrahão
- Laboratório de Bioquímica Celular, Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - José Roberto Meyer-Fernandes
- Laboratório de Bioquímica Celular, Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil.
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12
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Bru S, Martínez-Laínez JM, Hernández-Ortega S, Quandt E, Torres-Torronteras J, Martí R, Canadell D, Ariño J, Sharma S, Jiménez J, Clotet J. Polyphosphate is involved in cell cycle progression and genomic stability in Saccharomyces cerevisiae. Mol Microbiol 2016; 101:367-380. [PMID: 27072996 DOI: 10.1111/mmi.13396] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 04/04/2016] [Accepted: 04/09/2016] [Indexed: 11/27/2022]
Abstract
Polyphosphate (polyP) is a linear chain of up to hundreds of inorganic phosphate residues that is necessary for many physiological functions in all living organisms. In some bacteria, polyP supplies material to molecules such as DNA, thus playing an important role in biosynthetic processes in prokaryotes. In the present study, we set out to gain further insight into the role of polyP in eukaryotic cells. We observed that polyP amounts are cyclically regulated in Saccharomyces cerevisiae, and those mutants that cannot synthesise (vtc4Δ) or hydrolyse polyP (ppn1Δ, ppx1Δ) present impaired cell cycle progression. Further analysis revealed that polyP mutants show delayed nucleotide production and increased genomic instability. Based on these findings, we concluded that polyP not only maintains intracellular phosphate concentrations in response to fluctuations in extracellular phosphate levels, but also muffles internal cyclic phosphate fluctuations, such as those produced by the sudden demand of phosphate to synthetize deoxynucleotides just before and during DNA duplication. We propose that the presence of polyP in eukaryotic cells is required for the timely and accurate duplication of DNA.
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Affiliation(s)
- Samuel Bru
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | | | - Sara Hernández-Ortega
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Eva Quandt
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Javier Torres-Torronteras
- Research Group on Neuromuscular and Mitochondrial Disorders, Vall d'Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Spain
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Ramón Martí
- Research Group on Neuromuscular and Mitochondrial Disorders, Vall d'Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Spain
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - David Canadell
- Department of Biochemistry and Molecular Biology and the Institute of Biotechnology and Biomedicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Joaquin Ariño
- Department of Biochemistry and Molecular Biology and the Institute of Biotechnology and Biomedicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Sushma Sharma
- Department of Medical Biochemistry and Biophysics, Umeå University, Sweden
| | - Javier Jiménez
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
| | - Josep Clotet
- Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Barcelona, Spain
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13
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Linking Gene Expression in the Intestine to Production of Gametes Through the Phosphate Transporter PITR-1 in Caenorhabditis elegans. Genetics 2016; 204:153-62. [PMID: 27449055 PMCID: PMC5012382 DOI: 10.1534/genetics.116.188532] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 07/12/2016] [Indexed: 12/31/2022] Open
Abstract
Inorganic phosphate is an essential mineral for both prokaryotic and eukaryotic cell metabolism and structure. Its uptake into the cell is mediated by membrane-bound transporters and coupled to Na+ transport. Mammalian sodium-dependent Pi cotransporters have been grouped into three families NaPi-I, NaPi-II, and NaPi-III. Despite being discovered more than two decades ago, very little is known about requirements for NaPi-III transporters in vivo, in the context of intact animal models. Here we find that impaired function of the Caenorhabditis elegans NaPi-III transporter, pitr-1, results in decreased brood size and dramatically increased expression of vitellogenin by the worm intestine. Unexpectedly, we found that the effects of pitr-1 mutation on vitellogenin expression in the intestine could only be rescued by expression of pitr-1 in the germline, and not by expression of pitr-1 in the intestine itself. Our results indicate the existence of a signal from the germline that regulates gene expression in the intestine, perhaps linking nutrient export from the intestine to production of gametes by the germline.
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14
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Petrezsélyová S, López-Malo M, Canadell D, Roque A, Serra-Cardona A, Marqués MC, Vilaprinyó E, Alves R, Yenush L, Ariño J. Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study. PLoS One 2016; 11:e0158424. [PMID: 27362362 PMCID: PMC4928930 DOI: 10.1371/journal.pone.0158424] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 06/15/2016] [Indexed: 11/18/2022] Open
Abstract
Regulated expression of the Ena1 Na+-ATPase is a crucial event for adaptation to high salt and/or alkaline pH stress in the budding yeast Saccharomyces cerevisiae. ENA1 expression is under the control of diverse signaling pathways, including that mediated by the calcium-regulatable protein phosphatase calcineurin and its downstream transcription factor Crz1. We present here a quantitative study of the expression of Ena1 in response to alkalinization of the environment and we analyze the contribution of Crz1 to this response. Experimental data and mathematical models substantiate the existence of two stress-responsive Crz1-binding sites in the ENA1 promoter and estimate that the contribution of Crz1 to the early response of the ENA1 promoter is about 60%. The models suggest the existence of a second input with similar kinetics, which would be likely mediated by high pH-induced activation of the Snf1 kinase.
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Affiliation(s)
- Silvia Petrezsélyová
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
| | - María López-Malo
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
| | - David Canadell
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
| | - Alicia Roque
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
| | - Albert Serra-Cardona
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
| | - M. Carmen Marqués
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, 46022, Spain
| | - Ester Vilaprinyó
- IRB Lleida, Universitat de Lleida, Lleida 25198, Spain
- Universitat de Lleida, Lleida 25198, Spain
| | - Rui Alves
- IRB Lleida, Universitat de Lleida, Lleida 25198, Spain
- Universitat de Lleida, Lleida 25198, Spain
| | - Lynne Yenush
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, 46022, Spain
| | - Joaquín Ariño
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès 08193, Barcelona, Spain
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15
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Interactions Between Monovalent Cations and Nutrient Homeostasis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 892:271-289. [PMID: 26721278 DOI: 10.1007/978-3-319-25304-6_11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Maintenance of appropriate fluxes of monovalent cation is a requirement for growth and survival. In the budding yeast Saccharomyces cerevisiae an electrochemical gradient of H(+) is fundamental for the uptake of diverse cations, such as K(+), and of many other nutrients. In spite of early work suggesting that alterations in monovalent cation fluxes impact on the uptake and utilization of nutrients, such as phosphate anions, only recently this important aspect of the yeast physiology has been addressed and characterized in some detail. This chapter provides a historical background and summarizes the latest findings.
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16
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Samyn DR, Persson BL. Inorganic Phosphate and Sulfate Transport in S. cerevisiae. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 892:253-269. [PMID: 26721277 DOI: 10.1007/978-3-319-25304-6_10] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Inorganic ions such as phosphate and sulfate are essential macronutrients required for a broad spectrum of cellular functions and their regulation. In a constantly fluctuating environment microorganisms have for their survival developed specific nutrient sensing and transport systems ensuring that the cellular nutrient needs are met. This chapter focuses on the S. cerevisiae plasma membrane localized transporters, of which some are strongly induced under conditions of nutrient scarcity and facilitate the active uptake of inorganic phosphate and sulfate. Recent advances in studying the properties of the high-affinity phosphate and sulfate transporters by means of site-directed mutagenesis have provided further insight into the molecular mechanisms contributing to substrate selectivity and transporter functionality of this important class of membrane transporters.
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Affiliation(s)
- D R Samyn
- Department of Chemistry and Biomedical Sciences, Centre for Biomaterials Chemistry, Linnaeus University, 391 82, Kalmar, Sweden.
| | - B L Persson
- Department of Chemistry and Biomedical Sciences, Centre for Biomaterials Chemistry, Linnaeus University, 391 82, Kalmar, Sweden
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17
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Serra-Cardona A, Canadell D, Ariño J. Coordinate responses to alkaline pH stress in budding yeast. MICROBIAL CELL 2015; 2:182-196. [PMID: 28357292 PMCID: PMC5349140 DOI: 10.15698/mic2015.06.205] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Alkalinization of the medium represents a stress condition for the budding yeast Saccharomyces cerevisiae to which this organism responds with profound remodeling of gene expression. This is the result of the modulation of a substantial number of signaling pathways whose participation in the alkaline response has been elucidated within the last ten years. These regulatory inputs involve not only the conserved Rim101/PacC pathway, but also the calcium-activated phosphatase calcineurin, the Wsc1-Pkc1-Slt2 MAP kinase, the Snf1 and PKA kinases and oxidative stress-response pathways. The uptake of many nutrients is perturbed by alkalinization of the environment and, consequently, an impact on phosphate, iron/copper and glucose homeostatic mechanisms can also be observed. The analysis of available data highlights cases in which diverse signaling pathways are integrated in the gene promoter to shape the appropriate response pattern. Thus, the expression of different genes sharing the same signaling network can be coordinated, allowing functional coupling of their gene products.
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Affiliation(s)
- Albert Serra-Cardona
- Departament de Bioquímica i Biologia Molecular & Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain
| | - David Canadell
- Departament de Bioquímica i Biologia Molecular & Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain
| | - Joaquín Ariño
- Departament de Bioquímica i Biologia Molecular & Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain
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18
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Herrero E, Wellinger RE. Yeast as a model system to study metabolic impact of selenium compounds. MICROBIAL CELL 2015; 2:139-149. [PMID: 28357286 PMCID: PMC5349236 DOI: 10.15698/mic2015.05.200] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Inorganic Se forms such as selenate or selenite (the two more abundant forms in nature) can be toxic in Saccharomyces cerevisiae cells, which constitute an adequate model to study such toxicity at the molecular level and the functions participating in protection against Se compounds. Those Se forms enter the yeast cell through other oxyanion transporters. Once inside the cell, inorganic Se forms may be converted into selenide through a reductive pathway that in physiological conditions involves reduced glutathione with its consequent oxidation into diglutathione and alteration of the cellular redox buffering capacity. Selenide can subsequently be converted by molecular oxygen into elemental Se, with production of superoxide anions and other reactive oxygen species. Overall, these events result in DNA damage and dose-dependent reversible or irreversible protein oxidation, although additional oxidation of other cellular macromolecules cannot be discarded. Stress-adaptation pathways are essential for efficient Se detoxification, while activation of DNA damage checkpoint and repair pathways protects against Se-mediated genotoxicity. We propose that yeast may be used to improve our knowledge on the impact of Se on metal homeostasis, the identification of Se-targets at the DNA and protein levels, and to gain more insights into the mechanism of Se-mediated apoptosis.
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Affiliation(s)
- Enrique Herrero
- Departament de Ciències Mèdiques Bàsiques, Universitat de Lleida, IRBLleida, Rovira Roure 80, 25198 Lleida, Spain
| | - Ralf E Wellinger
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Universidad de Sevilla, 41092 Sevilla, Spain
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19
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Canadell D, González A, Casado C, Ariño J. Functional interactions between potassium and phosphate homeostasis in Saccharomyces cerevisiae. Mol Microbiol 2014; 95:555-72. [PMID: 25425491 DOI: 10.1111/mmi.12886] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2014] [Indexed: 12/29/2022]
Abstract
Maintenance of ion homeostatic mechanisms is essential for living cells, including the budding yeast Saccharomyces cerevisiae. Whereas the impact of changes in phosphate metabolism on metal ion homeostasis has been recently examined, the inverse effect is still largely unexplored. We show here that depletion of potassium from the medium or alteration of diverse regulatory pathways controlling potassium uptake, such as the Trk potassium transporters or the Pma1 H(+) -ATPase, triggers a response that mimics that of phosphate (Pi) deprivation, exemplified by accumulation of the high-affinity Pi transporter Pho84. This response is mediated by and requires the integrity of the PHO signaling pathway. Removal of potassium from the medium does not alter the amount of total or free intracellular Pi, but is accompanied by decreased ATP and ADP levels and rapid depletion of cellular polyphosphates. Therefore, our data do not support the notion of Pi being the major signaling molecule triggering phosphate-starvation responses. We also observe that cells with compromised potassium uptake cannot grow under limiting Pi conditions. The link between potassium and phosphate homeostasis reported here could explain the invasive phenotype, characteristic of nutrient deprivation, observed in potassium-deficient yeast cells.
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Affiliation(s)
- David Canadell
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
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20
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Serra-Cardona A, Petrezsélyová S, Canadell D, Ramos J, Ariño J. Coregulated expression of the Na+/phosphate Pho89 transporter and Ena1 Na+-ATPase allows their functional coupling under high-pH stress. Mol Cell Biol 2014; 34:4420-4435. [PMID: 25266663 PMCID: PMC4248728 DOI: 10.1128/mcb.01089-14] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 09/22/2014] [Indexed: 12/22/2022] Open
Abstract
The yeast Saccharomyces cerevisiae has two main high-affinity inorganic phosphate (Pi) transporters, Pho84 and Pho89, that are functionally relevant at acidic/neutral pH and alkaline pH, respectively. Upon Pi starvation, PHO84 and PHO89 are induced by the activation of the PHO regulon by the binding of the Pho4 transcription factor to specific promoter sequences. We show that PHO89 and PHO84 are induced by alkalinization of the medium with different kinetics and that the network controlling Pho89 expression in response to alkaline pH differs from that of other members of the PHO regulon. In addition to Pho4, the PHO89 promoter is regulated by the transcriptional activator Crz1 through the calcium-activated phosphatase calcineurin, and it is under the control of several repressors (Mig2, Nrg1, and Nrg2) coordinately regulated by the Snf1 protein kinase and the Rim101 transcription factor. This network mimics the one regulating expression of the Na(+)-ATPase gene ENA1, encoding a major determinant for Na(+) detoxification. Our data highlight a scenario in which the activities of Pho89 and Ena1 are functionally coordinated to sustain growth in an alkaline environment.
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Affiliation(s)
- Albert Serra-Cardona
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Silvia Petrezsélyová
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - David Canadell
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - José Ramos
- Departamento de Microbiología, Edificio Severo Ochoa, Universidad de Córdoba, Córdoba, Spain
| | - Joaquín Ariño
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
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21
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Kikuchi Y, Hijikata N, Yokoyama K, Ohtomo R, Handa Y, Kawaguchi M, Saito K, Ezawa T. Polyphosphate accumulation is driven by transcriptome alterations that lead to near-synchronous and near-equivalent uptake of inorganic cations in an arbuscular mycorrhizal fungus. THE NEW PHYTOLOGIST 2014; 204:638-649. [PMID: 25039900 DOI: 10.1111/nph.12937] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 06/11/2014] [Indexed: 05/09/2023]
Abstract
Arbuscular mycorrhizal (AM) fungi accumulate a massive amount of phosphate as polyphosphate to deliver to the host, but the underlying physiological and molecular mechanisms have yet to be elucidated. In the present study, the dynamics of cationic components during polyphosphate accumulation were investigated in conjunction with transcriptome analysis. Rhizophagus sp. HR1 was grown with Lotus japonicus under phosphorus-deficient conditions, and extraradical mycelia were harvested after phosphate application at prescribed intervals. Levels of polyphosphate, inorganic cations and amino acids were measured, and RNA-Seq was performed on the Illumina platform. Phosphate application triggered not only polyphosphate accumulation but also near-synchronous and near-equivalent uptake of Na(+) , K(+) , Ca(2+) and Mg(2+) , whereas no distinct changes in the levels of amino acids were observed. During polyphosphate accumulation, the genes responsible for mineral uptake, phosphate and nitrogen metabolism and the maintenance of cellular homeostasis were up-regulated. The results suggest that inorganic cations play a major role in neutralizing the negative charge of polyphosphate, and these processes are achieved by the orchestrated regulation of gene expression. Our findings provide, for the first time, a global picture of the cellular response to increased phosphate availability, which is the initial process of nutrient delivery in the associations.
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Affiliation(s)
- Yusuke Kikuchi
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Nowaki Hijikata
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Kaede Yokoyama
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Ryo Ohtomo
- National Agriculture and Food Research Organization, Hokkaido Agricultural Research Center, Sapporo, 062-8555, Japan
| | - Yoshihiro Handa
- Division of Symbiotic Systems, National Institute for Basic Biology, Okazaki, 444-8585, Japan
| | - Masayoshi Kawaguchi
- Division of Symbiotic Systems, National Institute for Basic Biology, Okazaki, 444-8585, Japan
| | - Katsuharu Saito
- Faculty of Agriculture, Shinshu University, Minamiminowa, 399-4598, Japan
| | - Tatsuhiro Ezawa
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
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22
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Defects in phosphate acquisition and storage influence virulence of Cryptococcus neoformans. Infect Immun 2014; 82:2697-712. [PMID: 24711572 DOI: 10.1128/iai.01607-14] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Nutrient acquisition and sensing are critical aspects of microbial pathogenesis. Previous transcriptional profiling indicated that the fungal pathogen Cryptococcus neoformans, which causes meningoencephalitis in immunocompromised individuals, encounters phosphate limitation during proliferation in phagocytic cells. We therefore tested the hypothesis that phosphate acquisition and polyphosphate metabolism are important for cryptococcal virulence. Deletion of the high-affinity uptake system interfered with growth on low-phosphate medium, perturbed the formation of virulence factors (capsule and melanin), reduced survival in macrophages, and attenuated virulence in a mouse model of cryptococcosis. Additionally, analysis of nutrient sensing functions for C. neoformans revealed regulatory connections between phosphate acquisition and storage and the iron regulator Cir1, cyclic AMP (cAMP)-dependent protein kinase A (PKA), and the calcium-calmodulin-activated protein phosphatase calcineurin. Deletion of the VTC4 gene encoding a polyphosphate polymerase blocked the ability of C. neoformans to produce polyphosphate. The vtc4 mutant behaved like the wild-type strain in interactions with macrophages and in the mouse infection model. However, the fungal load in the lungs was significantly increased in mice infected with vtc4 deletion mutants. In addition, the mutant was impaired in the ability to trigger blood coagulation in vitro, a trait associated with polyphosphate. Overall, this study reveals that phosphate uptake in C. neoformans is critical for virulence and that its regulation is integrated with key signaling pathways for nutrient sensing.
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23
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Characterization of the biochemical and biophysical properties of the Saccharomyces cerevisiae phosphate transporter Pho89. Biochem Biophys Res Commun 2013; 436:551-6. [DOI: 10.1016/j.bbrc.2013.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 06/06/2013] [Indexed: 11/21/2022]
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24
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Sengottaiyan P, Ruiz-Pavón L, Persson BL. Functional expression, purification and reconstitution of the recombinant phosphate transporter Pho89 of Saccharomyces cerevisiae. FEBS J 2013; 280:965-75. [PMID: 23216645 PMCID: PMC3633241 DOI: 10.1111/febs.12090] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 11/06/2012] [Accepted: 12/05/2012] [Indexed: 11/30/2022]
Abstract
The Saccharomyces cerevisiae high-affinity phosphate transporter Pho89 is a member of the inorganic phosphate (Pi) transporter (PiT) family, and shares significant homology with the type III Na(+)/Pi symporters, hPit1 and hPit2. Currently, detailed biochemical and biophysical analyses of Pho89 to better understand its transport mechanisms are limited, owing to the lack of purified Pho89 in an active form. In the present study, we expressed functional Pho89 in the cell membrane of Pichia pastoris, solubilized it in Triton X-100 and foscholine-12, and purified it by immobilized nickel affinity chromatography combined with size exclusion chromatography. The protein eluted as an oligomer on the gel filtration column, and SDS/PAGE followed by western blotting analysis revealed that the protein appeared as bands of approximately 63, 140 and 520 kDa, corresponding to the monomeric, dimeric and oligomeric masses of the protein, respectively. Proteoliposomes containing purified and reconstituted Pho89 showed Na(+)-dependent Pi transport activity driven by an artificially imposed electrochemical Na(+) gradient. This implies that Pho89 operates as a symporter. Moreover, its activity is sensitive to the Na(+) ionophore monensin. To our knowledge, this study represents the first report on the functional reconstitution of a Pi-coupled PiT family member.
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Russo-Abrahão T, Alves-Bezerra M, Majerowicz D, Freitas-Mesquita AL, Dick CF, Gondim KC, Meyer-Fernandes JR. Transport of inorganic phosphate in Leishmania infantum and compensatory regulation at low inorganic phosphate concentration. Biochim Biophys Acta Gen Subj 2012. [PMID: 23201200 DOI: 10.1016/j.bbagen.2012.11.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Proliferation of Leishmania infantum depends on exogenous inorganic phosphate (Pi) but little is known about energy metabolism and transport of Pi across the plasma membrane in Leishmania sp. METHODS We investigated the kinetics of 32Pi transport, the influence of H+ and K+ ionophores and inhibitors, and expression of the genes for the Na+:Pi and H+:Pi cotransporters. RESULTS The proton ionophore FCCP, bafilomycin A1 (vacuolar ATPase inhibitor), nigericin (K+ ionophore) and SCH28080 (an inhibitor of H+, K+-ATPase) all inhibited the transport of Pi. This transport showed Michaelis-Menten kinetics with K0.5 and Vmax values of 0.016±0.002mM and 564.9±18.06pmol×h-1×10-7cells, respectively. These values classify the Pi transporter of L. infantum among the high-affinity transporters, a group that includes Pho84 of Saccharomyces cerevisiae. Two sequences were identified in the L. infantum genome that code for phosphate transporters. However, transcription of the PHO84 transporter was 10-fold higher than the PHO89 transporter in this parasite. Accordingly, Pi transport and LiPho84 gene expression were modulated by environmental Pi variations. CONCLUSIONS These findings confirm the presence of a Pi transporter in L. infantum, similar to PHO84 in S. cerevisiae, that contributes to the acquisition of inorganic phosphate and could be involved in growth and survival of the promastigote forms of L. infantum. GENERAL SIGNIFICANCE This work provides the first description of a PHO84-like Pi transporter in a Trypanosomatide parasite of the genus Leishmania, responsible for many infections worldwide.
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Affiliation(s)
- T Russo-Abrahão
- Instituto de Microbiologia Professor Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Laboratório de Bioquímica Celular, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - M Alves-Bezerra
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - D Majerowicz
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - A L Freitas-Mesquita
- Laboratório de Bioquímica Celular, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - C F Dick
- Instituto de Microbiologia Professor Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Laboratório de Bioquímica Celular, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil
| | - K C Gondim
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - J R Meyer-Fernandes
- Laboratório de Bioquímica Celular, Instituto de Bioquímica Medica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brazil.
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Mutational analysis of conserved glutamic acids of Pho89, a Saccharomyces cerevisiae high-affinity inorganic phosphate:Na+ symporter. Biologia (Bratisl) 2012. [DOI: 10.2478/s11756-012-0118-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Regulation of amino acid, nucleotide, and phosphate metabolism in Saccharomyces cerevisiae. Genetics 2012; 190:885-929. [PMID: 22419079 DOI: 10.1534/genetics.111.133306] [Citation(s) in RCA: 377] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Ever since the beginning of biochemical analysis, yeast has been a pioneering model for studying the regulation of eukaryotic metabolism. During the last three decades, the combination of powerful yeast genetics and genome-wide approaches has led to a more integrated view of metabolic regulation. Multiple layers of regulation, from suprapathway control to individual gene responses, have been discovered. Constitutive and dedicated systems that are critical in sensing of the intra- and extracellular environment have been identified, and there is a growing awareness of their involvement in the highly regulated intracellular compartmentalization of proteins and metabolites. This review focuses on recent developments in the field of amino acid, nucleotide, and phosphate metabolism and provides illustrative examples of how yeast cells combine a variety of mechanisms to achieve coordinated regulation of multiple metabolic pathways. Importantly, common schemes have emerged, which reveal mechanisms conserved among various pathways, such as those involved in metabolite sensing and transcriptional regulation by noncoding RNAs or by metabolic intermediates. Thanks to the remarkable sophistication offered by the yeast experimental system, a picture of the intimate connections between the metabolomic and the transcriptome is becoming clear.
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Na+-dependent and Na+-independent mechanisms for inorganic phosphate uptake in Trypanosoma rangeli. Biochim Biophys Acta Gen Subj 2012; 1820:1001-8. [DOI: 10.1016/j.bbagen.2012.02.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 01/30/2012] [Accepted: 02/18/2012] [Indexed: 01/26/2023]
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Chan CX, Zäuner S, Wheeler G, Grossman AR, Prochnik SE, Blouin NA, Zhuang Y, Benning C, Berg GM, Yarish C, Eriksen RL, Klein AS, Lin S, Levine I, Brawley SH, Bhattacharya D. Analysis of Porphyra membrane transporters demonstrates gene transfer among photosynthetic eukaryotes and numerous sodium-coupled transport systems. PLANT PHYSIOLOGY 2012; 158:2001-12. [PMID: 22337920 PMCID: PMC3320202 DOI: 10.1104/pp.112.193896] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Membrane transporters play a central role in many cellular processes that rely on the movement of ions and organic molecules between the environment and the cell, and between cellular compartments. Transporters have been well characterized in plants and green algae, but little is known about transporters or their evolutionary histories in the red algae. Here we examined 482 expressed sequence tag contigs that encode putative membrane transporters in the economically important red seaweed Porphyra (Bangiophyceae, Rhodophyta). These contigs are part of a comprehensive transcriptome dataset from Porphyra umbilicalis and Porphyra purpurea. Using phylogenomics, we identified 30 trees that support the expected monophyly of red and green algae/plants (i.e. the Plantae hypothesis) and 19 expressed sequence tag contigs that show evidence of endosymbiotic/horizontal gene transfer involving stramenopiles. The majority (77%) of analyzed contigs encode transporters with unresolved phylogenies, demonstrating the difficulty in resolving the evolutionary history of genes. We observed molecular features of many sodium-coupled transport systems in marine algae, and the potential for coregulation of Porphyra transporter genes that are associated with fatty acid biosynthesis and intracellular lipid trafficking. Although both the tissue-specific and subcellular locations of the encoded proteins require further investigation, our study provides red algal gene candidates associated with transport functions and novel insights into the biology and evolution of these transporters.
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Phosphate homeostasis in the yeast Saccharomyces cerevisiae, the key role of the SPX domain-containing proteins. FEBS Lett 2012; 586:289-95. [PMID: 22285489 DOI: 10.1016/j.febslet.2012.01.036] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 01/11/2012] [Accepted: 01/16/2012] [Indexed: 12/27/2022]
Abstract
In the yeast Saccharomyces cerevisiae, a working model for nutrient homeostasis in eukaryotes, inorganic phosphate (Pi) homeostasis is regulated by the PHO pathway, a set of phosphate starvation induced genes, acting to optimize Pi uptake and utilization. Among these, a subset of proteins containing the SPX domain has been shown to be key regulators of Pi homeostasis. In this review, we summarize the recent progresses in elucidating the mechanisms controlling Pi homeostasis in yeast, focusing on the key roles of the SPX domain-containing proteins in these processes, as well as describing the future challenges and opportunities in this fast-moving field.
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Lazard M, Blanquet S, Fisicaro P, Labarraque G, Plateau P. Uptake of selenite by Saccharomyces cerevisiae involves the high and low affinity orthophosphate transporters. J Biol Chem 2010; 285:32029-37. [PMID: 20688911 DOI: 10.1074/jbc.m110.139865] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although the general cytotoxicity of selenite is well established, the mechanism by which this compound crosses cellular membranes is still unknown. Here, we show that in Saccharomyces cerevisiae, the transport system used opportunistically by selenite depends on the phosphate concentration in the growth medium. Both the high and low affinity phosphate transporters are involved in selenite uptake. When cells are grown at low P(i) concentrations, the high affinity phosphate transporter Pho84p is the major contributor to selenite uptake. When phosphate is abundant, selenite is internalized through the low affinity P(i) transporters (Pho87p, Pho90p, and Pho91p). Accordingly, inactivation of the high affinity phosphate transporter Pho84p results in increased resistance to selenite and reduced uptake in low P(i) medium, whereas deletion of SPL2, a negative regulator of low affinity phosphate uptake, results in exacerbated sensitivity to selenite. Measurements of the kinetic parameters for selenite and phosphate uptake demonstrate that there is a competition between phosphate and selenite ions for both P(i) transport systems. In addition, our results indicate that Pho84p is very selective for phosphate as compared with selenite, whereas the low affinity transporters discriminate less efficiently between the two ions. The properties of phosphate and selenite transport enable us to propose an explanation to the paradoxical increase of selenite toxicity when phosphate concentration in the growth medium is raised above 1 mm.
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Affiliation(s)
- Myriam Lazard
- Laboratoire de Biochimie, Ecole Polytechnique, F-91128 Palaiseau Cedex, France.
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John Wiley & Sons, Ltd.. Current awareness on yeast. Yeast 2009. [DOI: 10.1002/yea.1567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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