Use of Giardia, which appears to have a single nucleotide-sugar transporter for UDP-GlcNAc, to identify the UDP-Glc transporter of Entamoeba

Sulagna Banerjee, Jike Cui, Phillips W. Robbins, John Samuelson

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

Nucleotide-sugar transporters (NSTs) transport activated sugars (e.g. UDP-GlcNAc) from the cytosol to the lumen of the endoplasmic reticulum or Golgi apparatus where they are used to make glycoproteins and glycolipids. UDP-Glc is an important component of the N-glycan-dependent quality control (QC) system for protein folding. Because Entamoeba has this QC system while Giardia does not, we hypothesized that transfected Giardia might be used to identify the UDP-Glc transporter of Entamoeba. Here we show Giardia membranes transport UDP-GlcNAc and have apyrases, which hydrolyze nucleoside-diphosphates to make the antiporter nucleoside-monophosphate. The only NST of Giardia (GlNst), which we could identify, transports UDP-GlcNAc in transfected Saccharomyces and is present in perinuclear and peripheral vesicles and increases in expression during encystation. Entamoeba membranes transport three nucleotide-sugars (UDP-Gal, UDP-GlcNAc, and UDP-Glc), and Entamoeba has three NSTs, one of which has been shown previously to transport UDP-Gal (EhNst1). Here we show recombinant EhNst2 transports UDP-Glc in transfected Giardia, while recombinant EhNst3 transports UDP-GlcNAc in transfected Saccharomyces. In summary, all three NSTs of Entamoeba and the single NST of Giardia have been molecularly characterized, and transfected Giardia provides a new system for testing heterologous UDP-Glc transporters.

Original languageEnglish (US)
Pages (from-to)44-53
Number of pages10
JournalMolecular and Biochemical Parasitology
Volume159
Issue number1
DOIs
StatePublished - May 2008

Bibliographical note

Funding Information:
This work was supported by NIH grants AI048082 (to JS) and GM31318 (to PWR). Thanks to Heidi Elmendorf of Georgetown University for the Giardia expression vector. Thanks to Landon Moore of Boston University School of Medicine for help with fluorescence microscopy.

Keywords

  • Apyrase
  • Entamoeba
  • Giardia
  • N-glycan-dependent quality control of protein folding
  • Nucleotide-sugar transporter
  • Transfection

Fingerprint Dive into the research topics of 'Use of Giardia, which appears to have a single nucleotide-sugar transporter for UDP-GlcNAc, to identify the UDP-Glc transporter of Entamoeba'. Together they form a unique fingerprint.

Cite this