Recognition of Sulfation Pattern of Chondroitin Sulfate by Uronosyl 2-O-Sulfotransferase

Abstract

We have shown previously that a highly sulfated sequence, GalNAc(4,6-SO 4 )-GlcA(2SO 4 )-GalNAc(6SO 4 ), is present at the nonreducing terminal of chondroitin sulfate (CS), and this structure was synthesized from a unique sequence, GalNAc(4SO 4 )-GlcA(2SO 4 )-GalNAc(6SO 4 ), by sulfation with N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase. Uronosyl 2-O-sulfotrasferase (2OST), which transfers sulfate from 3-phosphoadenosine 5-phosphosulfate (PAPS) to position 2 of the GlcA residue of CS, is expected to be involved in synthesis of these structures; however, the specificity of 2OST concerning recognition of the sulfation pattern of the acceptor has largely remained unclear. In the present study, we examined the specificity of 2OST in terms of recognition of the sulfation pattern around the targeting GlcA residue. The recombinant 2OST could sulfate CS-A, CS-C, and desulfated dermatan sulfate. When

Is human placenta proteoglycan remodeling involved in pre-eclampsia?

“…This result correlates well with the mRNA data, since this enzyme has only one isoform in most of the genome-sequenced organisms, in contrast to multiple isoforms for almost all other HS and CS sulfotransferases [39]. CS-2OST transfers the sulfo group to the 2-OH position of the hexuronic acid that is adjacent to an Nacetylated galactosamine residue (GalNAc) carrying either a 6-O or 4-O sulfo group [41,42] and CS chains with 2-O-sulfo group exhibits a variety of biological functions [43,44,45]. In pre-eclampsia, the absence of 2-O-sulfo groups may reflect the fine tuning of CS chain that normally occurs in gravid placenta.…”

Mice Deficient in N-Acetylgalactosamine 4-Sulfate 6-O-Sulfotransferase Are Unable to Synthesize Chondroitin/Dermatan Sulfate containing N-Acetylgalactosamine 4,6-Bissulfate Residues and Exhibit Decreased Protease Activity in Bone Marrow-derived Mast Cells

“…Unlabeled PAPS was a gift from YAMASA Corp. (Choshi, Japan). N-Acetylgalactosamine 4,6-bissulfate was prepared from ⌬Di-diS E , as described previously (37).…”

N-Linked Oligosaccharides on Chondroitin 6-Sulfotransferase-1 Are Required for Production of the Active Enzyme, Golgi Localization, and Sulfotransferase Activity toward Keratan Sulfate

“…Sulfation of position 6 of the nonreducing terminal GalNAc(4SO 4 ) in the unique sequence found in the nonreducing terminal of CS, GalNAc(4SO 4 )-GlcA(2SO 4 )-GalNAc(6SO 4 )-, by GalNAc(4SO 4 ) 6-O-sulfotransferase was markedly stimulated by the penultimate GlcA(2SO 4 ) residue (17). Uronosyl 2-O-sulfotransferase selectively transferred sulfate to GlcA located in a unique sequence in CS, GalNAc(4SO 4 )-GlcA-GalNAc(6SO 4 ) (12). These observations strongly suggest that the order of participation of each sulfotransferase into the biosynthetic steps should be important to elaborate the functional fine structures in CS.…”

“…Subcellular localization of these sulfotransferases is probably relevant to determining the order. The purified C6ST-1, C4ST-1, and GalNAc(4SO 4 ) 6-O-sulfotransferase (18 -20) as well as the recombinant C6ST-1, C4ST-1, GalNAc(4SO 4 ) 6-O-sulfotransferase, and uronosyl 2-O-sulfotransferase (12,16,17) have been found to be glycoproteins containing relatively abundant N-linked oligosaccharides. It has been reported that N-glycans contained in various glycoproteins are involved in protein folding, ER-associated protein degradation, intracellular trafficking, and production of functional proteins (21)(22)(23)(24)(25).…”

“…Transfer of sulfate to the repeating unit is catalyzed by sulfotransferases having strict substrate specificity (1)(2)(3). To date, four sulfotransferase families involved in the biosynthesis of CS have been cloned, and their substrate specificities were characterized: chondroitin 6-sulfotransferase (C6ST) (4,5) and chondroitin 4-sulfotransferase (C4ST) (6 -9) transfer sulfate to position 6 and 4, respectively, of GalNAc residues; GalNAc(4SO 4 ) 6-O-sulfotransferase transfers sulfate to position 6 of GalNAc(4SO 4 ) residues (10); and uronosyl 2-O-sulfotransferase transfers sulfate to position 2 of GlcA or IdoUA (11,12). Of these sulfotransferases, mutations in mouse and human C6ST-1 are associated with a decrease in the naive T lymphocytes in the spleen (13) and chondrodysplasia (14), respectively, and a gene trap deletion of mouse C4ST-1 resulted in severe chondrodysplasia (15).…”