The INDIVIDUALIST

A Wiki about biochemical individuality

Glycomics

See Also

Description

Fucosyltransferases are enzymes catalyzing the transfer of fucose from a nucleoside diphosphate fucose to an acceptor molecule which is frequently another carbohydrate, a glycoprotein, or a glycolipid molecule. Elevated activity of some fucosyltransferases in human serum may serve as an indicator of malignancy.

The class includes EC 2.4.1.65; EC 2.4.1.68; EC 2.4.1.69; EC 2.4.1.89.

Discussion

Fucosylation has been shown to have important functions in cell-cell interaction and cell migration in connection with physiological and pathological processes such as fertilization, embryogenesis, lymphocyte trafcking, immune responses and cancer metastasis. The human genome encodes at least 13 different alpha1,3-fucosyltransferases.(1) Several other enzymes transfering fucose in alpha1,3-linkage, or the structures resulting from them, have been found in nearly all types of organism such as other mammals, insects, molluscs, plants and some bacteria. They differ in their substrate specicity, tissue distribution and various biochemical parameters.

Cell adhesion mediated by selectins and their carbohydrate ligands is involved in the adhesion of cancer cells to endothelial cells during the course of hematogenous metastasis of cancer. In patients with leukemia, this adhesion is involved in the extravascular infiltration of leukemic cells. Extravasation and tissue infiltration of malignant cells in patients with adult T-cell leukemia is mediated by the interaction of selectins and their carbohydrate ligand sialyl Lewis X, which is strongly and constitutively expressed on the leukemic cells. Constitutive expression of Lewis X in these cells is due to the transcriptional activation of Fuc-T VII, the rate-limiting enzyme in the sialyl Lewis X synthesis, induced by the Tax protein encoded by the human T-cell leukemia virus-1, the etiological virus for this leukemia. This is a good example corroborating the proposition that the abnormal expression of carbohydrate determinant at the surface of malignant cells is intimately associated with the genetic mechanism of malignant transformation of cells.(2)

Abstracts

alpha-L-fucosyltransferases from radish primary roots

Plant Physiol. 1996 February; 110(2): 665–673. H Misawa, Y Tsumuraya, Y Kaneko, and Y Hashimoto

  • A novel alpha-L-fucosyltransferase capable of transferring L-fucose (L-Fuc) from GDP-L-Fuc to the O-2 of alpha-L-arabinofuranosyl residue (GDP-L-Fuc:alpha-L-arabinofuranoside 2-alpha-L-fucosyltransferase) has been found in the microsomal fraction of primary roots from 6-d-old radish (Raphanus sativus L.) seedlings.

Links

References


1. Martinez-Duncker I, Mollicone R, Candelier J, Breton C, Oriol R. "A new superfamily of protein-O-fucosyltransferases, alpha 2-fucosyltransferases, and alpha 6-fucosyltransferases: phylogeny and identification of conserved peptide motifs". Glycobiology 2003;13 (12): 1C-5C.

2. Kannagi R.Transcriptional regulation of expression of carbohydrate ligands for cell adhesion molecules in the selectin family. Adv Exp Med Biol. 2001;491:267-78.

.