Glycobiology Advance Access published online on February 5, 2008
Glycobiology, doi:10.1093/glycob/cwn007
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A Novel 
1,2-Fucosyltransferase (CE2FT-2) In Caenorhabditis elegans Generates H-Type 3 Glycan Structures
1 Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 qlz{at}NordicBioscienceChina.com
2 The Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
3 Department of Molecular Cell Biology & Immunology, Glycoimmunology Group, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands im.vandie{at}vumc.nl
Address Correspondence to: Richard D. Cummings, Ph.D., Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Suite 4001, Atlanta, GA 30322, Tel: (404) 7275962, Fax: (404) 727—2738, Email: rdcummi{at}emory.edu
Received on May 14, 2007; accepted on January 29, 2008
The 
1,2-fucosyltransferase family (1,2FT) is the largest family of glycosyltransferases in the genome of the free-living nematode Caenorhabditis elegans, and early evidence suggests that each member may have unique activity. Here we describe a C. elegans gene (designated CE2FT-2) encoding an 1,2FT that has the potential to generate the sequence Fuc1–2Galβ1–3GalNAc-R, which is the H-type 3 blood group structure. The CE2FT-2 cDNA encodes a putative transmembrane protein that shows 
42% amino acid identity to a previously cloned C. elegans 1,2FT (termed CE2FT-1), but has very low identity (16–20%) to 1,2 FT sequences in humans, rabbits, and mice. A recombinant form of CE2FT-2 expressed in human 293T cells has high 1,2FT activity toward Galβ1–3GalNAc-O-pNP, but unexpectedly, the enzyme is inactive toward the acceptor Galβ-O-phenyl. Thus, CE2FT2 differs from all other 1,2FTs previously described from animals, that all utilize Galβ-O-phenyl. CE2FT-2 is expressed at all stages of worm development, but remarkably, promoter analysis of the CE2FT-2 gene using green fluorescent protein reporter constructs indicates that the CE2FT-2 is expressed exclusively in pharyngeal cells of the worm from embryo to adult stage. Because pharyngeal cells are known to secrete their glycoconjugates to the nematode surface, these results may indicate that products of CE2FT-2 contribute to interactions of the nematode with its environment, or are used as ligands for bacterial attachment. These findings, along with those on other 1,2FTs in C. elegans, suggest that each 1,2FT in this organism may have a unique acceptor specificity, expression pattern, and biological function.
Key words: Caenorhabditis elegans / fucosyltransferase / fucosylation / gene / green fluorescent protein