Molecular Cloning and Expression of Mouse and Human cDNAs Encoding Heparan Sulfate d-Glucosaminyl 3-O-Sulfotransferase

Abstract

The serine proteases of the intrinsic blood coagulation cascade are slowly neutralized by antithrombin (AT) 1 (reviewed in Ref. 1). This inhibition is secondary to the generation of 1:1 enzyme⅐AT complexes whose formation is dramatically enhanced by the mast cell product, heparin (2). Damus et al. (3) hypothesized that endothelial cell surface heparan sulfate proteoglycans (HSPGs) function in a similar fashion to accelerate coagulation enzyme inactivation by AT and therefore are responsible for the nonthrombogenic properties of blood vessels. We initially demonstrated that perfusion of the hind limbs of normal rodents and rodents deficient in mast cells with purified thrombin and AT leads to a greatly elevated rate of thrombin⅐AT complex formation and that the enzyme heparitinase as well as the natural heparin antagonist platelet factor 4 suppress the above acceleration (4, 5). We subsequently showed that cultured cloned bovine macrovascular and rodent microvascular endothelial cells synthesize both anticoagulant HSPG (HSPG act ) and nonanticoagulant HSPG (HSPG inact ) (6 -8). HSPG act bear glycosaminoglycan (GAG) chains that bind tightly to AT and accelerate thrombin⅐AT complex generation (6 -8).The biosynthesis of HSPG act requires generation of a core protein; assembly of a linkage region of four neutral sugars on specific serine attachment sites of the core protein; elongation of a GAG backbone composed of alternating N-acetylglu-

Expression Cloning of a Human Sulfotransferase That Directs the Synthesis of the HNK-1 Glycan on the Neural Cell Adhesion Molecule and Glycolipids

“…2 and Fig. 3) has homology with the sequences found in other Golgi-associated sulfotransferases such as chick chondroitin sulfate 6-Osulfotransferase, human galactosylceramide sulfotransferase, hamster heparan sulfate 2-O-sulfotransferase, and human heparan sulfate 3-O-sulfotransferase (33)(34)(35)(36). In particular, the RDP sequence (residue 189 -191) is completely conserved, and hydrophobic amino acids are shared among these amino acid sequences (Fig.…”

A role of Lys614 in the sulfotransferase activity of human heparan sulfate N‐deacetylase/N‐sulfotransferase

“…The Lys ~s and its corresponding lysines are in bold. 5'PSB represents the sequence motif that binds to the 5'-phosphosulfate of PAPS [12,16,20]. …”

Anticoagulant heparan sulfate: structural specificity and biosynthesis

“…The detailed substrate specificities of 3-OST isoforms are described below. Overexpression of 3-OST-1 and 3-OST-5 in cells significantly elevates the level of anticoagulant HS (41,42). The existence of multiple isoforms may explain why 3-OST-1 knockout mice failed to produce thrombotic phenotypes (41).…”