Molecular characterization of nucleocytosolic O-GlcNAc transferases of Giardia lamblia and Cryptosporidium parvum

Sulagna Banerjee, Phillips W. Robbins, John Samuelson

Research output: Contribution to journalArticle

34 Scopus citations

Abstract

O-Linked N-acetylglucosaminyltransferase (OGT) catalyzes the transfer of a single GlcNAc to the Ser or Thr of nucleocytoplasmic proteins. OGT activity, which may compete with that of kinases, is involved in signaling in animals and plants, and abnormalities in OGT activities have been associated with type 2 diabetes. Here, we show that ogt genes that predict enzymes with characteristic tetratricopeptide repeats and a spindly domain are present in some protists (Giardia, Cryptosporidium, Toxoplasma, and Dictyostelium) but are absent from the majority of protists examined (e.g., Plasmodium, Trypanosoma, Entamoeba, and Trichomonas). Similarly, ogt genes are present in some fungi but are absent from numerous other fungi, suggesting that secondary loss is an important contributor to the evolution of ogt genes. Nucleocytosolic extracts of Giardia and Cryptosporidium show OGT activity, and recombinant Giardia and Cryptosporidium OGTs are active in yeast and bacteria, respectively. These results suggest the possibility that O-GlcNAc modification of nucleocytosolic proteins also has function(s) in simple eukaryotes.

Original languageEnglish (US)
Pages (from-to)331-336
Number of pages6
JournalGlycobiology
Volume19
Issue number4
DOIs
StatePublished - Mar 20 2009

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Keywords

  • Cryptosporidium
  • Evolution
  • Giardia
  • O-GlcNAc transferase
  • Recombinant expression

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