Glypicans [, ]are a group of heparan sulphate proteoglycans which are anchored to cell membranes by a glycosylphosphatidylinositol (GPI) linkage. Structurally, these proteins consist of three separate domains:a) A signal sequence;b) An extracellular domain of about 500 residues that contains 12 conserved cysteines which is probably involved in disulphide bonds and also contains the sites of attachment of the heparan sulphate glycosaminoglycan side chains;c) A C-terminal hydrophobic region is post-translationally removed after formation of the GPI-anchor. Six members (GPC1-6) are known in vertebrates []. A role for GPC1 in pancreatic cancer progression has also been proposed [].
Glypicans [, ]are a group of heparan sulphate proteoglycans which are anchored to cell membranes by a glycosylphosphatidylinositol (GPI) linkage. Structurally, these proteins consist of three separate domains:a) A signal sequence;b) An extracellular domain of about 500 residues that contains 12 conserved cysteines probably involved in disulphide bonds and also contains the sites of attachment of the heparan sulphate glycosaminoglycan side chains;c) A C-terminal hydrophobic region that is post-translationally removed after formation of the GPI-anchor. Six members (GPC1-6) are known in vertebrates []. GPC3 encodes a putative extracellular proteoglycan, glypican 3 that is inferred to play an important role in growth control in embryonic mesodermal tissues in which it is selectively expressed. Initial western- and ligand-blotting experiments suggest that glypican 3 forms a complex with insulin-like growth factor 2 (IGF2), and might thereby modulate IGF2 action []. GPC3 gene defects in a wider range of overgrowth disorders []. GPC3 shares a number of features with the GPC1 [].
