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Xie SC, Wang Y, Morton CJ, Metcalfe RD, Dogovski C, Pasaje CFA, Dunn E, Luth MR, Kumpornsin K, Istvan ES, Park JS, Fairhurst KJ, Ketprasit N, Yeo T, Yildirim O, Bhebhe MN, Klug DM, Rutledge PJ, Godoy LC, Dey S, De Souza ML, Siqueira-Neto JL, Du Y, Puhalovich T, Amini M, Shami G, Loesbanluechai D, Nie S, Williamson N, Jana GP, Maity BC, Thomson P, Foley T, Tan DS, Niles JC, Han BW, Goldberg DE, Burrows J, Fidock DA, Lee MCS, Winzeler EA, Griffin MDW, Todd MH, Tilley L. Reaction hijacking inhibition of Plasmodium falciparum asparagine tRNA synthetase. Nat Commun 2024; 15:937. [PMID: 38297033 PMCID: PMC10831071 DOI: 10.1038/s41467-024-45224-z] [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: 07/24/2023] [Accepted: 01/16/2024] [Indexed: 02/02/2024] Open
Abstract
Malaria poses an enormous threat to human health. With ever increasing resistance to currently deployed drugs, breakthrough compounds with novel mechanisms of action are urgently needed. Here, we explore pyrimidine-based sulfonamides as a new low molecular weight inhibitor class with drug-like physical parameters and a synthetically accessible scaffold. We show that the exemplar, OSM-S-106, has potent activity against parasite cultures, low mammalian cell toxicity and low propensity for resistance development. In vitro evolution of resistance using a slow ramp-up approach pointed to the Plasmodium falciparum cytoplasmic asparaginyl-tRNA synthetase (PfAsnRS) as the target, consistent with our finding that OSM-S-106 inhibits protein translation and activates the amino acid starvation response. Targeted mass spectrometry confirms that OSM-S-106 is a pro-inhibitor and that inhibition of PfAsnRS occurs via enzyme-mediated production of an Asn-OSM-S-106 adduct. Human AsnRS is much less susceptible to this reaction hijacking mechanism. X-ray crystallographic studies of human AsnRS in complex with inhibitor adducts and docking of pro-inhibitors into a model of Asn-tRNA-bound PfAsnRS provide insights into the structure-activity relationship and the selectivity mechanism.
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Affiliation(s)
- Stanley C Xie
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Yinuo Wang
- School of Pharmacy, University College London, London, WC1N 1AX, UK
| | - Craig J Morton
- Biomedical Manufacturing Program, CSIRO, Clayton South, VIC, Australia
| | - Riley D Metcalfe
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, USA
| | - Con Dogovski
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Charisse Flerida A Pasaje
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Elyse Dunn
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Madeline R Luth
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Krittikorn Kumpornsin
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, CB10 1SA, UK
- Calibr, Division of the Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Eva S Istvan
- Division of Infectious Diseases, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Joon Sung Park
- Research Institute of Pharmaceutical Sciences and Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kate J Fairhurst
- Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, NY, 10032, USA
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Nutpakal Ketprasit
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Tomas Yeo
- Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, NY, 10032, USA
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Okan Yildirim
- Chemical Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | | | - Dana M Klug
- School of Pharmacy, University College London, London, WC1N 1AX, UK
| | - Peter J Rutledge
- School of Chemistry, University of Sydney, Camperdown, NSW, 2006, Australia
| | - Luiz C Godoy
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Sumanta Dey
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Mariana Laureano De Souza
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Jair L Siqueira-Neto
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Yawei Du
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Tanya Puhalovich
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Mona Amini
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Gerry Shami
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | | | - Shuai Nie
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Nicholas Williamson
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Gouranga P Jana
- TCG Lifesciences Private Limited, Salt-Lake Electronics Complex, Kolkata, India
| | - Bikash C Maity
- TCG Lifesciences Private Limited, Salt-Lake Electronics Complex, Kolkata, India
| | - Patrick Thomson
- School of Chemistry, The University of Edinburgh, Edinburgh, EH9 3JJ, UK
| | - Thomas Foley
- School of Chemistry, The University of Edinburgh, Edinburgh, EH9 3JJ, UK
| | - Derek S Tan
- Chemical Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Byung Woo Han
- Research Institute of Pharmaceutical Sciences and Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Daniel E Goldberg
- Division of Infectious Diseases, Department of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Jeremy Burrows
- Medicines for Malaria Venture, 20, Route de Pré-Bois, 1215, Geneva 15, Switzerland
| | - David A Fidock
- Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, NY, 10032, USA
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
- Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY, 10032, USA
| | - Marcus C S Lee
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, CB10 1SA, UK
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, University of Dundee, Dundee, DD1 4HN, UK
| | - Elizabeth A Winzeler
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA, 92093, USA.
| | - Michael D W Griffin
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia.
| | - Matthew H Todd
- School of Pharmacy, University College London, London, WC1N 1AX, UK.
- Structural Genomics Consortium, University College London, London, WC1N 1AX, UK.
| | - Leann Tilley
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia.
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Xie SC, Wang Y, Morton CJ, Metcalfe RD, Dogovski C, Pasaje CFA, Dunn E, Luth MR, Kumpornsin K, Istvan ES, Park JS, Fairhurst KJ, Ketprasit N, Yeo T, Yildirim O, Bhebhe MN, Klug DM, Rutledge PJ, Godoy LC, Dey S, De Souza ML, Siqueira-Neto JL, Du Y, Puhalovich T, Amini M, Shami G, Loesbanluechai D, Nie S, Williamson N, Jana GP, Maity BC, Thomson P, Foley T, Tan DS, Niles JC, Han BW, Goldberg DE, Burrows J, Fidock DA, Lee MC, Winzeler EA, Griffin MDW, Todd MH, Tilley L. Reaction hijacking inhibition of Plasmodium falciparum asparagine tRNA synthetase. RESEARCH SQUARE 2023:rs.3.rs-3198291. [PMID: 37546892 PMCID: PMC10402266 DOI: 10.21203/rs.3.rs-3198291/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Malaria poses an enormous threat to human health. With ever increasing resistance to currently deployed drugs, breakthrough compounds with novel mechanisms of action are urgently needed. Here, we explore pyrimidine-based sulfonamides as a new low molecular weight inhibitor class with drug-like physical parameters and a synthetically accessible scaffold. We show that the exemplar, OSM-S-106, has potent activity against parasite cultures, low mammalian cell toxicity and low propensity for resistance development. In vitro evolution of resistance using a slow ramp-up approach pointed to the Plasmodium falciparum cytoplasmic asparaginyl tRNA synthetase (PfAsnRS) as the target, consistent with our finding that OSM-S-106 inhibits protein translation and activates the amino acid starvation response. Targeted mass spectrometry confirms that OSM-S-106 is a pro-inhibitor and that inhibition of PfAsnRS occurs via enzyme-mediated production of an Asn-OSM-S-106 adduct. Human AsnRS is much less susceptible to this reaction hijacking mechanism. X-ray crystallographic studies of human AsnRS in complex with inhibitor adducts and docking of pro-inhibitors into a model of Asn-tRNA-bound PfAsnRS provide insights into the structure activity relationship and the selectivity mechanism.
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Affiliation(s)
- Stanley C. Xie
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Yinuo Wang
- School of Pharmacy, University College London, London WC1N 1AX, United Kingdom
| | - Craig J. Morton
- Biomedical Manufacturing Program, CSIRO, Clayton South, Australia
| | - Riley D. Metcalfe
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Con Dogovski
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | | | - Elyse Dunn
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Madeline R Luth
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Krittikorn Kumpornsin
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, CB10 1SA, United Kingdom
- Calibr, Division of the Scripps Research Institute, La Jolla, CA 92037, USA
| | - Eva S Istvan
- Division of Infectious Diseases, Department of Medicine, Washington University in St. Louis, USA
| | - Joon Sung Park
- Research Institute of Pharmaceutical Sciences & Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
| | - Kate J. Fairhurst
- Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, NY 10032, USA
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY 10032, USA
| | - Nutpakal Ketprasit
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Tomas Yeo
- Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, NY 10032, USA
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY 10032, USA
| | - Okan Yildirim
- Chemical Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | | | - Dana M. Klug
- School of Pharmacy, University College London, London WC1N 1AX, United Kingdom
| | - Peter J. Rutledge
- School of Chemistry, University of Sydney, Camperdown, NSW 2006, Australia
| | - Luiz C. Godoy
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sumanta Dey
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mariana Laureano De Souza
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Jair L. Siqueira-Neto
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Yawei Du
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Tanya Puhalovich
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Mona Amini
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Gerry Shami
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | | | - Shuai Nie
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Nicholas Williamson
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Gouranga P. Jana
- TCG Lifesciences Private Limited, Salt-lake Electronics Complex, Kolkata, India
| | - Bikash C. Maity
- TCG Lifesciences Private Limited, Salt-lake Electronics Complex, Kolkata, India
| | - Patrick Thomson
- School of Chemistry, The University of Edinburgh, Edinburgh EH9 3JJ, United Kingdom
| | - Thomas Foley
- School of Chemistry, The University of Edinburgh, Edinburgh EH9 3JJ, United Kingdom
| | - Derek S. Tan
- Chemical Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Byung Woo Han
- Research Institute of Pharmaceutical Sciences & Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
| | - Daniel E Goldberg
- Division of Infectious Diseases, Department of Medicine, Washington University in St. Louis, USA
| | - Jeremy Burrows
- Medicines for Malaria Venture, 20, Route de Pré-Bois 1215, Geneva 15, Switzerland
| | - David A. Fidock
- Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, NY 10032, USA
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY 10032, USA
- Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Marcus C.S. Lee
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, CB10 1SA, United Kingdom
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, University of Dundee, Dundee DD1 4HN, United Kingdom
| | - Elizabeth A. Winzeler
- Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Michael D. W. Griffin
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Matthew H. Todd
- School of Pharmacy, University College London, London WC1N 1AX, United Kingdom
- Structural Genomics Consortium, University College London, London WC1N 1AX, United Kingdom
| | - Leann Tilley
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
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Deveci G, Kamil M, Kina U, Temel BA, Aly ASI. Genetic disruption of nucleoside transporter 4 reveals its critical roles in malaria parasite sporozoite functions. Pathog Glob Health 2023; 117:284-292. [PMID: 36003062 PMCID: PMC10081079 DOI: 10.1080/20477724.2022.2112880] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
Abstract
All protozoan parasites are lacking the pathway to synthesize purines de novo and therefore they depend on their host cells to provide purines. A number of highly conserved nucleoside transporter (NT) proteins are encoded in malaria parasite genomes, of which NT1 is characterized in Plasmodium falciparum and P. yoelii as a plasma membrane protein that is responsible for salvage of purines from the host, and NT2 is an endoplasmic membrane NT protein. Whereas NT3 is only present in primate malaria parasites, little is known about NT4, which is conserved in all malaria parasite species. Herein, we targeted NT4 gene for deletion in P. berghei. NT4 knockout parasites developed normally as blood stages, ookinetes and formed oocysts with sporozoites compared with wild-type (WT) P. berghei ANKA parasites. However, nt4(-) sporozoites showed significantly decreased egress from oocysts to hemolymph, significant reduction of colonization of the salivary glands, and complete abolishment of infection of the mammalian host by salivary gland and hemolymph sporozoites. Therefore, we identify NT4 as a NT that is important, not for replication and growth, but for sporozoite infectivity functions.
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Affiliation(s)
- Gozde Deveci
- Aly Lab, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Istanbul, Turkey
- Department of Biotechnology, Institute of Health Sciences, Bezmialem Vakif University, Istanbul, Turkey
| | - Mohd Kamil
- Aly Lab, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Istanbul, Turkey
| | - Umit Kina
- Aly Lab, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Istanbul, Turkey
- Department of Biotechnology, Institute of Health Sciences, Bezmialem Vakif University, Istanbul, Turkey
| | - Binnur Aydogan Temel
- Department of Biotechnology, Institute of Health Sciences, Bezmialem Vakif University, Istanbul, Turkey
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Bezmialem Vakif University, Istanbul, Turkey
| | - Ahmed S. I. Aly
- Aly Lab, Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, Istanbul, Turkey
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An Uninvited Seat at the Dinner Table: How Apicomplexan Parasites Scavenge Nutrients from the Host. Microorganisms 2021; 9:microorganisms9122592. [PMID: 34946193 PMCID: PMC8707601 DOI: 10.3390/microorganisms9122592] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 12/24/2022] Open
Abstract
Obligate intracellular parasites have evolved a remarkable assortment of strategies to scavenge nutrients from the host cells they parasitize. Most apicomplexans form a parasitophorous vacuole (PV) within the invaded cell, a replicative niche within which they survive and multiply. As well as providing a physical barrier against host cell defense mechanisms, the PV membrane (PVM) is also an important site of nutrient uptake that is essential for the parasites to sustain their metabolism. This means nutrients in the extracellular milieu are separated from parasite metabolic machinery by three different membranes, the host plasma membrane, the PVM, and the parasite plasma membrane (PPM). In order to facilitate nutrient transport from the extracellular environment into the parasite itself, transporters on the host cell membrane of invaded cells can be modified by secreted and exported parasite proteins to maximize uptake of key substrates to meet their metabolic demand. To overcome the second barrier, the PVM, apicomplexan parasites secrete proteins contained in the dense granules that remodel the vacuole and make the membrane permissive to important nutrients. This bulk flow of host nutrients is followed by a more selective uptake of substrates at the PPM that is operated by specific transporters of this third barrier. In this review, we recapitulate and compare the strategies developed by Apicomplexa to scavenge nutrients from their hosts, with particular emphasis on transporters at the parasite plasma membrane and vacuolar solute transporters on the parasite intracellular digestive organelle.
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Lopez JAV, Nogawa T, Yoshida K, Futamura Y, Osada H. 2-Methylthio-N7-methyl-cis-zeatin, a new antimalarial natural product isolated from a Streptomyces culture. Biosci Biotechnol Biochem 2021; 86:31-36. [PMID: 34734225 DOI: 10.1093/bbb/zbab192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/26/2021] [Indexed: 11/14/2022]
Abstract
2-Methylthio-N7-methyl-cis-zeatin (1) was isolated from the culture broth of Streptomyces sp. 80H647 along with two known purine derivatives, 5'-methylthioinosine (2) and AT-265 (dealanylascamycin, 3). The structure elucidation of compound 1 was accomplished by HRMS and NMR analyses. It inhibited the growth of Plasmodium falciparum 3D7 with a GI50 of 2.4 μM and had no effect on the growth of Arabidopsis at 2 μM. This is the first report of an N7-methylated zeatin-type natural product from Streptomyces and as an antimalarial compound.
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Affiliation(s)
- Julius Adam V Lopez
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Toshihiko Nogawa
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Kazuko Yoshida
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Yushi Futamura
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Hiroyuki Osada
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
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Campagnaro GD, de Koning HP. Purine and pyrimidine transporters of pathogenic protozoa - conduits for therapeutic agents. Med Res Rev 2020; 40:1679-1714. [PMID: 32144812 DOI: 10.1002/med.21667] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/12/2020] [Accepted: 02/18/2020] [Indexed: 02/06/2023]
Abstract
Purines and pyrimidines are essential nutrients for any cell. Most organisms are able to synthesize their own purines and pyrimidines, but this ability was lost in protozoans that adapted to parasitism, leading to a great diversification in transporter activities in these organisms, especially for the acquisition of amino acids and nucleosides from their hosts throughout their life cycles. Many of these transporters have been shown to have sufficiently different substrate affinities from mammalian transporters, making them good carriers for therapeutic agents. In this review, we summarize the knowledge obtained on purine and pyrimidine activities identified in protozoan parasites to date and discuss their importance for the survival of these parasites and as drug carriers, as well as the perspectives of developments in the field.
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Affiliation(s)
- Gustavo D Campagnaro
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, 120 University Place, Glasgow, UK
| | - Harry P de Koning
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, 120 University Place, Glasgow, UK
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7
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Martin RE. The transportome of the malaria parasite. Biol Rev Camb Philos Soc 2019; 95:305-332. [PMID: 31701663 DOI: 10.1111/brv.12565] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 10/02/2019] [Accepted: 10/04/2019] [Indexed: 12/15/2022]
Abstract
Membrane transport proteins, also known as transporters, control the movement of ions, nutrients, metabolites, and waste products across the membranes of a cell and are central to its biology. Proteins of this type also serve as drug targets and are key players in the phenomenon of drug resistance. The malaria parasite has a relatively reduced transportome, with only approximately 2.5% of its genes encoding transporters. Even so, assigning functions and physiological roles to these proteins, and ascertaining their contributions to drug action and drug resistance, has been very challenging. This review presents a detailed critique and synthesis of the disruption phenotypes, protein subcellular localisations, protein functions (observed or predicted), and links to antimalarial drug resistance for each of the parasite's transporter genes. The breadth and depth of the gene disruption data are particularly impressive, with at least one phenotype determined in the parasite's asexual blood stage for each transporter gene, and multiple phenotypes available for 76% of the genes. Analysis of the curated data set revealed there to be relatively little redundancy in the Plasmodium transportome; almost two-thirds of the parasite's transporter genes are essential or required for normal growth in the asexual blood stage of the parasite, and this proportion increased to 78% when the disruption phenotypes available for the other parasite life stages were included in the analysis. These observations, together with the finding that 22% of the transportome is implicated in the parasite's resistance to existing antimalarials and/or drugs within the development pipeline, indicate that transporters are likely to serve, or are already serving, as drug targets. Integration of the different biological and bioinformatic data sets also enabled the selection of candidates for transport processes known to be essential for parasite survival, but for which the underlying proteins have thus far remained undiscovered. These include potential transporters of pantothenate, isoleucine, or isopentenyl diphosphate, as well as putative anion-selective channels that may serve as the pore component of the parasite's 'new permeation pathways'. Other novel insights into the parasite's biology included the identification of transporters for the potential development of antimalarial treatments, transmission-blocking drugs, prophylactics, and genetically attenuated vaccines. The syntheses presented herein set a foundation for elucidating the functions and physiological roles of key members of the Plasmodium transportome and, ultimately, to explore and realise their potential as therapeutic targets.
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Affiliation(s)
- Rowena E Martin
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
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8
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Sosa Y, Deniskin R, Frame IJ, Steiginga MS, Bandyopadhyay D, Graybill TL, Kallal LA, Ouellette MT, Pope AJ, Widdowson KL, Young RJ, Akabas MH. Identification via a Parallel Hit Progression Strategy of Improved Small Molecule Inhibitors of the Malaria Purine Uptake Transporter that Inhibit Plasmodium falciparum Parasite Proliferation. ACS Infect Dis 2019; 5:1738-1753. [PMID: 31373203 DOI: 10.1021/acsinfecdis.9b00168] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Emerging resistance to current antimalarial medicines underscores the importance of identifying new drug targets and novel compounds. Malaria parasites are purine auxotrophic and import purines via the Plasmodium falciparum equilibrative nucleoside transporter type 1 (PfENT1). We previously showed that PfENT1 inhibitors block parasite proliferation in culture. Our goal was to identify additional, possibly more optimal chemical starting points for a drug discovery campaign. We performed a high throughput screen (HTS) of GlaxoSmithKline's 1.8 million compound library with a yeast-based assay to identify PfENT1 inhibitors. We used a parallel progression strategy for hit validation and expansion, with an emphasis on chemical properties in addition to potency. In one arm, the most active hits were tested for human cell toxicity; 201 had minimal toxicity. The second arm, hit expansion, used a scaffold-based substructure search with the HTS hits as templates to identify over 2000 compounds; 123 compounds had activity. Of these 324 compounds, 175 compounds inhibited proliferation of P. falciparum parasite strain 3D7 with IC50 values between 0.8 and ∼180 μM. One hundred forty-two compounds inhibited PfENT1 knockout (pfent1Δ) parasite growth, indicating they also hit secondary targets. Thirty-two hits inhibited growth of 3D7 but not pfent1Δ parasites. Thus, PfENT1 inhibition was sufficient to block parasite proliferation. Therefore, PfENT1 may be a viable target for antimalarial drug development. Six compounds with novel chemical scaffolds were extensively characterized in yeast-, parasite-, and human-erythrocyte-based assays. The inhibitors showed similar potencies against drug sensitive and resistant P. falciparum strains. They represent attractive starting points for development of novel antimalarial drugs.
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Affiliation(s)
| | | | | | - Matthew S. Steiginga
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Deepak Bandyopadhyay
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Todd L. Graybill
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Lorena A. Kallal
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Michael T. Ouellette
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Andrew J. Pope
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Katherine L. Widdowson
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Robert J. Young
- Platform Technology & Science and Discovery Partners in Academia, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
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9
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Cheviet T, Lefebvre-Tournier I, Wein S, Peyrottes S. Plasmodium Purine Metabolism and Its Inhibition by Nucleoside and Nucleotide Analogues. J Med Chem 2019; 62:8365-8391. [PMID: 30964283 DOI: 10.1021/acs.jmedchem.9b00182] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Malaria still affects around 200 million people and is responsible for more than 400,000 deaths per year, mostly children in subequatorial areas. This disease is caused by parasites of the Plasmodium genus. Only a few WHO-recommended treatments are available to prevent or cure plasmodial infections, but genetic mutations in the causal parasites have led to onset of resistance against all commercial antimalarial drugs. New drugs and targets are being investigated to cope with this emerging problem, including enzymes belonging to the main metabolic pathways, while nucleoside and nucleotide analogues are also a promising class of potential drugs. This review highlights the main metabolic pathways targeted for the development of potential antiplasmodial therapies based on nucleos(t)ide analogues, as well as the different series of purine-containing nucleoside and nucleotide derivatives designed to inhibit Plasmodium falciparum purine metabolism.
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Affiliation(s)
- Thomas Cheviet
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247 UM-CNRS-ENSCM , Université Montpellier, Equipe Nucléosides & Effecteurs Phosphorylés , Place E. Bataillon, cc 1704 , 34095 Montpellier , France
| | - Isabelle Lefebvre-Tournier
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247 UM-CNRS-ENSCM , Université Montpellier, Equipe Nucléosides & Effecteurs Phosphorylés , Place E. Bataillon, cc 1704 , 34095 Montpellier , France
| | - Sharon Wein
- Dynamique des Interactions Membranaires Normales et Pathologiques (DIMNP), UMR 5235 UM-CNRS , Université Montpellier , Place E. Bataillon , 34095 Montpellier , France
| | - Suzanne Peyrottes
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247 UM-CNRS-ENSCM , Université Montpellier, Equipe Nucléosides & Effecteurs Phosphorylés , Place E. Bataillon, cc 1704 , 34095 Montpellier , France
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10
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Kumar S, Bhardwaj TR, Prasad DN, Singh RK. Drug targets for resistant malaria: Historic to future perspectives. Biomed Pharmacother 2018; 104:8-27. [PMID: 29758416 DOI: 10.1016/j.biopha.2018.05.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/22/2018] [Accepted: 05/07/2018] [Indexed: 01/05/2023] Open
Abstract
New antimalarial targets are the prime need for the discovery of potent drug candidates. In order to fulfill this objective, antimalarial drug researches are focusing on promising targets in order to develop new drug candidates. Basic metabolism and biochemical process in the malaria parasite, i.e. Plasmodium falciparum can play an indispensable role in the identification of these targets. But, the emergence of resistance to antimalarial drugs is an escalating comprehensive problem with the progress of antimalarial drug development. The development of resistance has highlighted the need for the search of novel antimalarial molecules. The pharmaceutical industries are committed to new drug development due to the global recognition of this life threatening resistance to the currently available antimalarial therapy. The recent developments in the understanding of parasite biology are exhilarating this resistance issue which is further being ignited by malaria genome project. With this background of information, this review was aimed to highlights and provides useful information on various present and promising treatment approaches for resistant malaria, new progresses, pursued by some innovative targets that have been explored till date. This review also discusses modern and futuristic multiple approaches to antimalarial drug discovery and development with pictorial presentations highlighting the various targets, that could be exploited for generating promising new drugs in the future for drug resistant malaria.
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Affiliation(s)
- Sahil Kumar
- School of Pharmacy and Emerging Sciences, Baddi University of Emerging Sciences & Technology, Baddi, Dist. Solan, 173205, Himachal Pradesh, India
| | - T R Bhardwaj
- School of Pharmacy and Emerging Sciences, Baddi University of Emerging Sciences & Technology, Baddi, Dist. Solan, 173205, Himachal Pradesh, India
| | - D N Prasad
- Department of Pharmaceutical Chemistry, Shivalik College of Pharmacy, Nangal, Dist. Rupnagar, 140126, Punjab, India
| | - Rajesh K Singh
- Department of Pharmaceutical Chemistry, Shivalik College of Pharmacy, Nangal, Dist. Rupnagar, 140126, Punjab, India.
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11
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Meier A, Erler H, Beitz E. Targeting Channels and Transporters in Protozoan Parasite Infections. Front Chem 2018; 6:88. [PMID: 29637069 PMCID: PMC5881087 DOI: 10.3389/fchem.2018.00088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 03/12/2018] [Indexed: 12/25/2022] Open
Abstract
Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e., channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease), and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).
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Affiliation(s)
- Anna Meier
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Holger Erler
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Eric Beitz
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
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12
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Andrabi SBA, Tahara M, Matsubara R, Toyama T, Aonuma H, Sakakibara H, Suematsu M, Tanabe K, Nozaki T, Nagamune K. Plant hormone cytokinins control cell cycle progression and plastid replication in apicomplexan parasites. Parasitol Int 2017; 67:47-58. [PMID: 28344153 DOI: 10.1016/j.parint.2017.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 03/21/2017] [Indexed: 01/12/2023]
Abstract
Cytokinins are plant hormones that are involved in regulation of cell proliferation, cell cycle progression, and cell and plastid development. Here, we show that the apicomplexan parasites Toxoplasma gondii and Plasmodium berghei, an opportunistic human pathogen and a rodent malaria agent, respectively, produce cytokinins via a biosynthetic pathway similar to that in plants. Cytokinins regulate the growth and cell cycle progression of T. gondii by mediating expression of the cyclin gene TgCYC4. A natural form of cytokinin, trans-zeatin (t-zeatin), upregulated expression of this cyclin, while a synthetic cytokinin, thidiazuron, downregulated its expression. Immunofluorescence microscopy and quantitative PCR analysis showed that t-zeatin increased the genome-copy number of apicoplast, which are non-photosynthetic plastid, in the parasite, while thidiazuron led to their disappearance. Thidiazuron inhibited growth of T. gondii and Plasmodium falciparum, a human malaria parasite, suggesting that thidiazuron has therapeutic potential as an inhibitor of apicomplexan parasites.
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Affiliation(s)
- Syed Bilal Ahmad Andrabi
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan; School of Medicine, Keio University, Tokyo, Japan
| | - Michiru Tahara
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan; Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Ryuma Matsubara
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan; Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Tomoko Toyama
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hiroka Aonuma
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan; Department of Tropical Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | | | | | - Kazuyuki Tanabe
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Tomoyoshi Nozaki
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan; Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Kisaburo Nagamune
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan; Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan.
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13
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Arora A, Deniskin R, Sosa Y, Nishtala SN, Henrich PP, Kumar TRS, Fidock DA, Akabas MH. Substrate and Inhibitor Specificity of the Plasmodium berghei Equilibrative Nucleoside Transporter Type 1. Mol Pharmacol 2016; 89:678-85. [PMID: 27048953 DOI: 10.1124/mol.115.101386] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 04/04/2016] [Indexed: 12/22/2022] Open
Abstract
Malaria is a critical public health issue in the tropical world, causing extensive morbidity and mortality. Infection by unicellular, obligate intracellular Plasmodium parasites causes malaria. The emergence of resistance to current antimalarial drugs necessitates the development of novel therapeutics. A potential novel drug target is the purine import transporter. Because Plasmodium parasites are purine auxotrophic, they must import purines from their host to fulfill metabolic requirements. They import purines via equilibrative nucleoside transporter 1 (ENT1) homologs. Recently, we used a yeast-based high-throughput screen to identify inhibitors of the P. falciparum ENT1 (PfENT1) that kill P. falciparum parasites in culture. P. berghei infection of mice is an animal model for human malaria. Because P. berghei ENT1 (PbENT1) shares only 60% amino acid sequence identity with PfENT1, we sought to characterize PbENT1 and its sensitivity to our PfENT1 inhibitors. We expressed PbENT1 in purine auxotrophic yeast and used radiolabeled substrate uptake to characterize its function. We showed that PbENT1 transports both purines and pyrimidines. It preferred nucleosides compared with nucleobases. Inosine (IC50 = 3.7 µM) and guanosine (IC50 = 21.3 µM) had the highest affinities. Our recently discovered PfENT1 inhibitors were equally effective against both PbENT1- and PfENT1-mediated purine uptake. The PfENT1 inhibitors are at least 10-fold more potent against PfENT1 than human hENT1. They kill P. berghei parasites in 24-hour ex vivo culture. Thus, the P. berghei murine malaria model may be useful to evaluate the efficacy of PfENT1 inhibitors in vivo and their therapeutic potential for treatment of malaria.
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Affiliation(s)
- Avish Arora
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - Roman Deniskin
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - Yvett Sosa
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - Sita Nirupama Nishtala
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - Philipp P Henrich
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - T R Santha Kumar
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - David A Fidock
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
| | - Myles H Akabas
- Departments of Physiology and Biophysics (A.A., R.D., Y.S., S.N.N., M.H.A.) and Neuroscience and Medicine (M.H.A.), Albert Einstein College of Medicine, Bronx, New York; and Departments Microbiology and Immunology (P.P.H., T.R.S.K., D.A.F.) and Medicine (D.A.F.), Columbia University Medical Center, New York, New York
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14
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Targeting the Plasmodium vivax equilibrative nucleoside transporter 1 (PvENT1) for antimalarial drug development. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2015; 6:1-11. [PMID: 26862473 PMCID: PMC4706624 DOI: 10.1016/j.ijpddr.2015.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 11/18/2015] [Accepted: 11/25/2015] [Indexed: 11/26/2022]
Abstract
Infection with Plasmodium falciparum and vivax cause most cases of malaria. Emerging resistance to current antimalarial medications makes new drug development imperative. Ideally a new antimalarial drug should treat both falciparum and vivax malaria. Because malaria parasites are purine auxotrophic, they rely on purines imported from the host erythrocyte via Equilibrative Nucleoside Transporters (ENTs). Thus, the purine import transporters represent a potential target for antimalarial drug development. For falciparum parasites the primary purine transporter is the P. falciparum Equilibrative Nucleoside Transporter Type 1 (PfENT1). Recently we identified potent PfENT1 inhibitors with nanomolar IC50 values using a robust, yeast-based high throughput screening assay. In the current work we characterized the Plasmodium vivax ENT1 (PvENT1) homologue and its sensitivity to the PfENT1 inhibitors. We expressed a yeast codon-optimized PvENT1 gene in Saccharomyces cerevisiae. PvENT1-expressing yeast imported both purines ([3H]adenosine) and pyrimidines ([3H]uridine), whereas wild type (fui1Δ) yeast did not. Based on radiolabel substrate uptake inhibition experiments, inosine had the lowest IC50 (3.8 μM), compared to guanosine (14.9 μM) and adenosine (142 μM). For pyrimidines, thymidine had an IC50 of 183 μM (vs. cytidine and uridine; mM range). IC50 values were higher for nucleobases compared to the corresponding nucleosides; hypoxanthine had a 25-fold higher IC50 than inosine. The archetypal human ENT1 inhibitor 4-nitrobenzylthioinosine (NBMPR) had no effect on PvENT1, whereas dipyridamole inhibited PvENT1, albeit with a 40 μM IC50, a 1000-fold less sensitive than human ENT1 (hENT1). The PfENT1 inhibitors blocked transport activity of PvENT1 and the five known naturally occurring non-synonymous single nucleotide polymorphisms (SNPs) with similar IC50 values. Thus, the PfENT1 inhibitors also target PvENT1. This implies that development of novel antimalarial drugs that target both falciparum and vivax ENT1 may be feasible. PvENT1 can be functionally expressed in Saccharomyces cerevisiae. PvENT1 transports purine and pyrimidine nucleosides and nucleobases but does not transport nucleotides. PvENT1 is inhibited by recently described PfENT1 inhibitors with similar potency. Identified PvENT1 non-synonymous SNPs do not change PfENT1 inhibitor potency. Plasmodium ENTs may be feasible target for development of novel antimalarial drugs.
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Key Words
- ACT, Artemisinin-based Combination Therapies
- CQ, chloroquine
- Drug development
- EC50, concentration causing 50% of maximal effect
- ENT, equilibrative nucleoside transporter
- EV, empty vector
- HTS, high throughput screen
- IC50, concentration causing 50% inhibition
- Malaria
- NBMPR, 4-nitrobenzylthioinosine
- Nucleoside/nucleobase transport
- Parasite
- PfENT1, P. falciparum ENT type 1
- Plasmodium vivax
- Purines
- PvENT1, P. vivax ENT type 1
- SDM, synthetic defined media
- SNP, single nucleotide polymorphism
- Single-nucleotide polymorphism (SNP)
- Transporter
- WHO, World Health Organization
- WT, wild type
- hENT1, human ENT type 1
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Spillman NJ, Kirk K. The malaria parasite cation ATPase PfATP4 and its role in the mechanism of action of a new arsenal of antimalarial drugs. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2015; 5:149-62. [PMID: 26401486 PMCID: PMC4559606 DOI: 10.1016/j.ijpddr.2015.07.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/03/2015] [Accepted: 07/08/2015] [Indexed: 11/28/2022]
Abstract
The intraerythrocytic malaria parasite, Plasmodium falciparum, maintains a low cytosolic Na(+) concentration and the plasma membrane P-type cation translocating ATPase 'PfATP4' has been implicated as playing a key role in this process. PfATP4 has been the subject of significant attention in recent years as mutations in this protein confer resistance to a growing number of new antimalarial compounds, including the spiroindolones, the pyrazoles, the dihydroisoquinolones, and a number of the antimalarial agents in the Medicines for Malaria Venture's 'Malaria Box'. On exposure of parasites to these compounds there is a rapid disruption of cytosolic Na(+). Whether, and if so how, such chemically distinct compounds interact with PfATP4, and how such interactions lead to parasite death, is not yet clear. The fact that multiple different chemical classes have converged upon PfATP4 highlights its significance as a potential target for new generation antimalarial agents. A spiroindolone (KAE609, now known as cipargamin) has progressed through Phase I and IIa clinical trials with favourable results. In this review we consider the physiological role of PfATP4, summarise the current repertoire of antimalarial compounds for which PfATP4 is implicated in their mechanism of action, and provide an outlook on translation from target identification in the laboratory to patient treatment in the field.
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Affiliation(s)
- Natalie Jane Spillman
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia ; Department of Medicine (Infectious Diseases), Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Kiaran Kirk
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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Srivastava A, Creek DJ, Evans KJ, De Souza D, Schofield L, Müller S, Barrett MP, McConville MJ, Waters AP. Host reticulocytes provide metabolic reservoirs that can be exploited by malaria parasites. PLoS Pathog 2015; 11:e1004882. [PMID: 26042734 PMCID: PMC4456406 DOI: 10.1371/journal.ppat.1004882] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 04/14/2015] [Indexed: 11/18/2022] Open
Abstract
Human malaria parasites proliferate in different erythroid cell types during infection. Whilst Plasmodium vivax exhibits a strong preference for immature reticulocytes, the more pathogenic P. falciparum primarily infects mature erythrocytes. In order to assess if these two cell types offer different growth conditions and relate them to parasite preference, we compared the metabolomes of human and rodent reticulocytes with those of their mature erythrocyte counterparts. Reticulocytes were found to have a more complex, enriched metabolic profile than mature erythrocytes and a higher level of metabolic overlap between reticulocyte resident parasite stages and their host cell. This redundancy was assessed by generating a panel of mutants of the rodent malaria parasite P. berghei with defects in intermediary carbon metabolism (ICM) and pyrimidine biosynthesis known to be important for P. falciparum growth and survival in vitro in mature erythrocytes. P. berghei ICM mutants (pbpepc-, phosphoenolpyruvate carboxylase and pbmdh-, malate dehydrogenase) multiplied in reticulocytes and committed to sexual development like wild type parasites. However, P. berghei pyrimidine biosynthesis mutants (pboprt-, orotate phosphoribosyltransferase and pbompdc-, orotidine 5'-monophosphate decarboxylase) were restricted to growth in the youngest forms of reticulocytes and had a severe slow growth phenotype in part resulting from reduced merozoite production. The pbpepc-, pboprt- and pbompdc- mutants retained virulence in mice implying that malaria parasites can partially salvage pyrimidines but failed to complete differentiation to various stages in mosquitoes. These findings suggest that species-specific differences in Plasmodium host cell tropism result in marked differences in the necessity for parasite intrinsic metabolism. These data have implications for drug design when targeting mature erythrocyte or reticulocyte resident parasites.
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Affiliation(s)
- Anubhav Srivastava
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
| | - Darren J. Creek
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Krystal J. Evans
- Walter and Eliza Hall Institute of Medical Research, Division of Infection and Immunity, Parkville, Victoria, Australia
| | - David De Souza
- Metabolomics Australia, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
| | - Louis Schofield
- Walter and Eliza Hall Institute of Medical Research, Division of Infection and Immunity, Parkville, Victoria, Australia
- Australian Institute of Tropical Health and Medicine, Centre for Biodiscovery and Molecular Development of Therapeutics, James Cook University, Townsville, Australia
| | - Sylke Müller
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
| | - Michael P. Barrett
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
| | - Malcolm J. McConville
- Metabolomics Australia, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Andrew P. Waters
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Scotland, United Kingdom
- * E-mail:
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Frame IJ, Deniskin R, Rinderspacher A, Katz F, Deng SX, Moir RD, Adjalley SH, Coburn-Flynn O, Fidock DA, Willis IM, Landry DW, Akabas MH. Yeast-based high-throughput screen identifies Plasmodium falciparum equilibrative nucleoside transporter 1 inhibitors that kill malaria parasites. ACS Chem Biol 2015; 10:775-83. [PMID: 25602169 DOI: 10.1021/cb500981y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Equilibrative transporters are potential drug targets; however, most functional assays involve radioactive substrate uptake that is unsuitable for high-throughput screens (HTS). We developed a robust yeast-based growth assay that is potentially applicable to many equilibrative transporters. As proof of principle, we applied our approach to Equilibrative Nucleoside Transporter 1 of the malarial parasite Plasmodium falciparum (PfENT1). PfENT1 inhibitors might serve as novel antimalarial drugs since PfENT1-mediated purine import is essential for parasite proliferation. To identify PfENT1 inhibitors, we screened 64 560 compounds and identified 171 by their ability to rescue the growth of PfENT1-expressing fui1Δ yeast in the presence of a cytotoxic PfENT1 substrate, 5-fluorouridine (5-FUrd). In secondary assays, nine of the highest activity compounds inhibited PfENT1-dependent growth of a purine auxotrophic yeast strain with adenosine as the sole purine source (IC50 0.2-2 μM). These nine compounds completely blocked [(3)H]adenosine uptake into PfENT1-expressing yeast and erythrocyte-free trophozoite-stage parasites (IC50 5-50 nM), and inhibited chloroquine-sensitive and -resistant parasite proliferation (IC50 5-50 μM). Wild-type (WT) parasite IC50 values were up to 4-fold lower compared to PfENT1-knockout (pfent1Δ) parasites. pfent1Δ parasite killing showed a delayed-death phenotype not observed with WT. We infer that, in parasites, the compounds inhibit both PfENT1 and a secondary target with similar efficacy. The secondary target identity is unknown, but its existence may reduce the likelihood of parasites developing resistance to PfENT1 inhibitors. Our data support the hypothesis that blocking purine transport through PfENT1 may be a novel and compelling approach for antimalarial drug development.
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Affiliation(s)
- I. J. Frame
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Roman Deniskin
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Alison Rinderspacher
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Francine Katz
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Shi-Xian Deng
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Robyn D. Moir
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Sophie H. Adjalley
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Olivia Coburn-Flynn
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - David A. Fidock
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Ian M. Willis
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Donald W. Landry
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
| | - Myles H. Akabas
- Department of Physiology & Biophysics, ‡Department of Biochemistry, §Department of Neuroscience, and ∥Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, United States
- Department of Medicine and #Department of Microbiology & Immunology, Columbia University Medical Center, 630 and 701 West 168th Street, New York, New York 10032, United States
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Frame IJ, Deniskin R, Arora A, Akabas MH. Purine import into malaria parasites as a target for antimalarial drug development. Ann N Y Acad Sci 2014; 1342:19-28. [PMID: 25424653 DOI: 10.1111/nyas.12568] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Infection with Plasmodium species parasites causes malaria. Plasmodium parasites are purine auxotrophs. In all life cycle stages, they require purines for RNA and DNA synthesis and other cellular metabolic processes. Purines are imported from the host erythrocyte by equilibrative nucleoside transporters (ENTs). They are processed via purine salvage pathway enzymes to form the required purine nucleotides. The Plasmodium falciparum genome encodes four putative ENTs (PfENT1-4). Genetic, biochemical, and physiologic evidence suggest that PfENT1 is the primary purine transporter supplying the purine salvage pathway. Protein mass spectrometry shows that PfENT1 is expressed in all parasite stages. PfENT1 knockout parasites are not viable in culture at purine concentrations found in human blood (<10 μM). Thus, PfENT1 is a potential target for novel antimalarial drugs, but no PfENT1 inhibitors have been identified to test the hypothesis. Identifying inhibitors of PfENT1 is an essential step to validate PfENT1 as a potential antimalarial drug target.
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Affiliation(s)
- I J Frame
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
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Abstract
As it grows and replicates within the erythrocytes of its host the malaria parasite takes up nutrients from the extracellular medium, exports metabolites and maintains a tight control over its internal ionic composition. These functions are achieved via membrane transport proteins, integral membrane proteins that mediate the passage of solutes across the various membranes that separate the biochemical machinery of the parasite from the extracellular environment. Proteins of this type play a key role in antimalarial drug resistance, as well as being candidate drug targets in their own right. This review provides an overview of recent work on the membrane transport biology of the malaria parasite-infected erythrocyte, encompassing both the parasite-induced changes in the membrane transport properties of the host erythrocyte and the cell physiology of the intracellular parasite itself.
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Dean P, Major P, Nakjang S, Hirt RP, Embley TM. Transport proteins of parasitic protists and their role in nutrient salvage. FRONTIERS IN PLANT SCIENCE 2014; 5:153. [PMID: 24808897 PMCID: PMC4010794 DOI: 10.3389/fpls.2014.00153] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 04/01/2014] [Indexed: 05/02/2023]
Abstract
The loss of key biosynthetic pathways is a common feature of important parasitic protists, making them heavily dependent on scavenging nutrients from their hosts. This is often mediated by specialized transporter proteins that ensure the nutritional requirements of the parasite are met. Over the past decade, the completion of several parasite genome projects has facilitated the identification of parasite transporter proteins. This has been complemented by functional characterization of individual transporters along with investigations into their importance for parasite survival. In this review, we summarize the current knowledge on transporters from parasitic protists and highlight commonalities and differences in the transporter repertoires of different parasitic species, with particular focus on characterized transporters that act at the host-pathogen interface.
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Affiliation(s)
- Paul Dean
- *Correspondence: Paul Dean and T. Martin Embley, The Medical School, Institute for Cell and Molecular Biosciences, Newcastle University, Catherine Cookson Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK e-mail: ;
| | | | | | | | - T. Martin Embley
- *Correspondence: Paul Dean and T. Martin Embley, The Medical School, Institute for Cell and Molecular Biosciences, Newcastle University, Catherine Cookson Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK e-mail: ;
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Brunner R, Ng CL, Aissaoui H, Akabas MH, Boss C, Brun R, Callaghan PS, Corminboeuf O, Fidock DA, Frame IJ, Heidmann B, Le Bihan A, Jenö P, Mattheis C, Moes S, Müller IB, Paguio M, Roepe PD, Siegrist R, Voss T, Welford RWD, Wittlin S, Binkert C. UV-triggered affinity capture identifies interactions between the Plasmodium falciparum multidrug resistance protein 1 (PfMDR1) and antimalarial agents in live parasitized cells. J Biol Chem 2013; 288:22576-83. [PMID: 23754276 DOI: 10.1074/jbc.m113.453159] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
A representative of a new class of potent antimalarials with an unknown mode of action was recently described. To identify the molecular target of this class of antimalarials, we employed a photo-reactive affinity capture method to find parasite proteins specifically interacting with the capture compound in living parasitized cells. The capture reagent retained the antimalarial properties of the parent molecule (ACT-213615) and accumulated within parasites. We identified several proteins interacting with the capture compound and established a functional interaction between ACT-213615 and PfMDR1. We surmise that PfMDR1 may play a role in the antimalarial activity of the piperazine-containing compound ACT-213615.
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Affiliation(s)
- Ralf Brunner
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, CH-4002 Basel, Switzerland
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Experimental cerebral malaria is suppressed by disruption of nucleoside transporter 1 but not purine nucleoside phosphorylase. Biochem Biophys Res Commun 2013; 432:504-8. [DOI: 10.1016/j.bbrc.2013.02.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 02/03/2013] [Indexed: 11/23/2022]
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