Functional Characterization of Leishmania Transporters

Summary

Principal Investigator: Scott Landfear
Abstract: The objective of this proposal is to study the biological function of glucose transporters in the parasite Leishmania mexicana. Leishmania species cause disease in an estimated 12 million individuals worldwide and are a major public health problem. Identification of genes and proteins that serve essential functions for the parasite is critical for the identification of targets for development of novel drugs. Previous work has demonstrated that the glucose transporters of L. mexicana, integral membrane proteins that mediate the uptake of glucose and related hexose sugars, are essential in the amastigote stage of the life cycle that infects vertebrates and causes disease. Hence, this proposal will focus upon the biochemical functions of parasite glucose transporters and attempt to explain why they are essential for the disease causing stage of the parasite life cycle. The first aim will examine each of the 3 principal fates of glucose in the cell and determine which of them is/are impaired by when glucose transporters are genetically ablated by targeted gene deletion. These fates of glucose include: i) incorporation into glycoconjugates and complex carbohydrates, ii) metabolism via the pentose phosphate pathway to generate NADPH and ribose phosphate, and iii) metabolism via glycolysis. These experiments will establish which of these 3 pathways are affected by the inability of a glucose transporter null mutant to import hexoses and which of these deficiencies may contribute to the non-viability of this null mutant as amastigotes. The second aim will investigate the specific functions of the 3 glucose transporter isoforms GT1, GT2, and GT3. Null mutants in each of these genes will be prepared and their phenotypes assessed in both the promastigote and amastigote stages of the life cycle. These experiments will help elucidate distinct functions for each of the 3 glucose transporters expressed by this parasite. Overall, this proposal will provide a detailed biochemical and genetic dissection of glucose transporter function and the essential role of these permeases in the parasite life cycle.
Funding Period: ----------------1991 - ---------------2011-
more information: NIH RePORT

Top Publications

  1. ncbi Metabolic changes in glucose transporter-deficient Leishmania mexicana and parasite virulence
    Dayana Rodriguez-Contreras
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Biol Chem 281:20068-76. 2006
  2. pmc 'Transient' genetic suppression facilitates generation of hexose transporter null mutants in Leishmania mexicana
    Xiuhong Feng
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Microbiol 87:412-29. 2013
  3. pmc Both sequence and context are important for flagellar targeting of a glucose transporter
    Khoa D Tran
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    J Cell Sci 125:3293-8. 2012
  4. pmc KHARON1 mediates flagellar targeting of a glucose transporter in Leishmania mexicana and is critical for viability of infectious intracellular amastigotes
    Khoa D Tran
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Biol Chem 288:22721-33. 2013
  5. pmc An expression system to screen for inhibitors of parasite glucose transporters
    Torben Feistel
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Biochem Parasitol 162:71-6. 2008
  6. ncbi Drugs and transporters in kinetoplastid protozoa
    Scott M Landfear
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
    Adv Exp Med Biol 625:22-32. 2008
  7. ncbi Comprehensive examination of charged intramembrane residues in a nucleoside transporter
    Raquel Valdes
    Department of Molecular Microbiology and Immunology and Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Biol Chem 281:22647-55. 2006
  8. pmc Phenotypic characterization of a glucose transporter null mutant in Leishmania mexicana
    Dayana Rodriguez-Contreras
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Biochem Parasitol 153:9-18. 2007
  9. pmc Mammalian glucose permease GLUT1 facilitates transport of arsenic trioxide and methylarsonous acid
    Zijuan Liu
    Department of Biochemistry and Molecular Biology, Wayne State University, School of Medicine, Detroit, MI 48201, USA
    Biochem Biophys Res Commun 351:424-30. 2006
  10. pmc A constitutive pan-hexose permease for the Plasmodium life cycle and transgenic models for screening of antimalarial sugar analogs
    Martin Blume
    Department of Molecular Parasitology, Humboldt University, Berlin, Germany
    FASEB J 25:1218-29. 2011

Scientific Experts

  • S M Landfear
  • Mohamad Hamdi
  • Dayana Rodriguez-Contreras
  • Xiuhong Feng
  • Khoa D Tran
  • Stephen M Beverley
  • Torben Feistel
  • Larry David
  • Martin Blume
  • Elizabeth Kruvand
  • Cosmo Buffalo
  • H G Archie Bouwer
  • Zijuan Liu
  • Raquel Valdes
  • Richard J S Burchmore
  • Johannes Elferich
  • Wandy Beatty
  • Tamsen Polley
  • David Scott
  • Phillip A Yates
  • Lon Fye Lye
  • Danielle P Vieira
  • Ujwal Shinde
  • Marco Sanchez
  • Nishith Gupta
  • P K Umasankar
  • Kai Matuschewski
  • Richard Lucius
  • Natalia S Akopyants
  • Armando Jardim
  • Ashley McCormack
  • Marion Hliscs
  • David H Peyton
  • Cheryl A Hodson
  • Kristie M Keeney
  • Eckhard Boles
  • Buddy Ullman
  • Wei Liu
  • Barry P Rosen
  • Xuan Jiang
  • Marco A Sanchez

Detail Information

Publications15

  1. ncbi Metabolic changes in glucose transporter-deficient Leishmania mexicana and parasite virulence
    Dayana Rodriguez-Contreras
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Biol Chem 281:20068-76. 2006
    ....
  2. pmc 'Transient' genetic suppression facilitates generation of hexose transporter null mutants in Leishmania mexicana
    Xiuhong Feng
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Microbiol 87:412-29. 2013
    ..These studies provide the first evidence that genetic suppression can occur by providing critical biological functions transiently. This novel form of genetic suppression may extend to other genes, pathways and organisms...
  3. pmc Both sequence and context are important for flagellar targeting of a glucose transporter
    Khoa D Tran
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    J Cell Sci 125:3293-8. 2012
    ..It is likely that the NPM motif is recognized by currently unknown protein-binding partners that mediate flagellar targeting of membrane-associated proteins...
  4. pmc KHARON1 mediates flagellar targeting of a glucose transporter in Leishmania mexicana and is critical for viability of infectious intracellular amastigotes
    Khoa D Tran
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Biol Chem 288:22721-33. 2013
    ..Of considerable interest, Kh1 null mutants are strongly compromised for growth as amastigotes within host macrophages. Thus, KH1 is also important for the disease causing stage of the parasite life cycle. ..
  5. pmc An expression system to screen for inhibitors of parasite glucose transporters
    Torben Feistel
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Biochem Parasitol 162:71-6. 2008
    ..The ability of this expression system to identify specific glucose transporter inhibitors was demonstrated using 3-O-undec-10-enyl-d-glucose, a previously described specific inhibitor of PfHT...
  6. ncbi Drugs and transporters in kinetoplastid protozoa
    Scott M Landfear
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon 97239, USA
    Adv Exp Med Biol 625:22-32. 2008
    ..A summary of recent work on Leishmania transporters for glucose and for purines is provided as an example of permeases that are being studied in molecular detail...
  7. ncbi Comprehensive examination of charged intramembrane residues in a nucleoside transporter
    Raquel Valdes
    Department of Molecular Microbiology and Immunology and Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239, USA
    J Biol Chem 281:22647-55. 2006
    ..1 permease. These results imply that the Glu94, Lys153, and Asp374 residues may play central roles in the mechanism of substrate translocation in LdNT1.1...
  8. pmc Phenotypic characterization of a glucose transporter null mutant in Leishmania mexicana
    Dayana Rodriguez-Contreras
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Biochem Parasitol 153:9-18. 2007
    ..These results underscore the importance of glucose transporters in the parasite life cycle and suggest reasons for their non-viability in the disease-causing amastigote stage...
  9. pmc Mammalian glucose permease GLUT1 facilitates transport of arsenic trioxide and methylarsonous acid
    Zijuan Liu
    Department of Biochemistry and Molecular Biology, Wayne State University, School of Medicine, Detroit, MI 48201, USA
    Biochem Biophys Res Commun 351:424-30. 2006
    ..Thus GLUT1 may be a major pathway uptake of both inorganic and methylated arsenicals in erythrocytes or the epithelial cells of the blood-brain barrier, contributing to arsenic-related cardiovascular problems and neurotoxicity...
  10. pmc A constitutive pan-hexose permease for the Plasmodium life cycle and transgenic models for screening of antimalarial sugar analogs
    Martin Blume
    Department of Molecular Parasitology, Humboldt University, Berlin, Germany
    FASEB J 25:1218-29. 2011
    ..This work provides a platform to facilitate the development of drugs against malaria, and it suggests a disease-control aspect by reducing parasite transmission...
  11. pmc Remodeling of protein and mRNA expression in Leishmania mexicana induced by deletion of glucose transporter genes
    Xiuhong Feng
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, 3181 S W Sam Jackson Park Road, Portland, OR 97239, USA
    Mol Biochem Parasitol 175:39-48. 2011
    ..Some of these changes in protein expression may reflect an adaptive response of the parasites to limitation of glucose...
  12. ncbi Glucose transporters in parasitic protozoa
    Scott M Landfear
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA
    Methods Mol Biol 637:245-62. 2010
    ..The study of these transporters also illuminates many aspects of the basic biology of Leishmania, trypanosomes, and malaria parasites...
  13. pmc Arsenic transport by zebrafish aquaglyceroporins
    Mohamad Hamdi
    Dept of Biological Sciences, Oakland University, Rochester, MI 48309, USA
    BMC Mol Biol 10:104. 2009
    ..Members of the aquaglyceroporin family have been shown to actively conduct AsIII and its organic metabolite, monomethylarsenite (MAsIII). However, the transport of AsIII and MAsIII in in any fish species has not been characterized...
  14. pmc Amplification of an alternate transporter gene suppresses the avirulent phenotype of glucose transporter null mutants in Leishmania mexicana
    Xiuhong Feng
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA
    Mol Microbiol 71:369-81. 2009
    ..These results underscore the importance of hexose transporters for the infectious stage of the parasite life cycle...
  15. ncbi Transporters for drug delivery and as drug targets in parasitic protozoa
    S M Landfear
    Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon, USA
    Clin Pharmacol Ther 87:122-5. 2010
    ..These permeases could be employed in two distinct strategies for drug development: (i) targeting selective delivery of drugs to the parasite and (ii) developing drugs that inhibit essential parasite permeases...