Molecular Cloning and Characterization of GalNAc 4-Sulfotransferase Expressed in Human Pituitary Gland

Background: ␣-Dystroglycan undergoes extensive glycosylation required for the interaction between ␣-dystroglycan and its ligands such as laminin. Results: HNK-1ST suppressed the glycosylation and reduced the ligand binding activity of ␣-dystroglycan. Conclusion:The sulfotransferase activity of HNK-1ST is essential for the modulation of ␣-dystroglycan. Significance: This study identifies a novel role for HNK-1ST as a regulator of the functional glycans on ␣-dystroglycan other than HNK-1 biosynthesis.

Section: Involvement Of Hnk-1st In Functional Glycan Synthesis On ␣-Dmentioning

confidence: 99%

Human Natural Killer-1 Sulfotransferase (HNK-1ST)-induced Sulfate Transfer Regulates Laminin-binding Glycans on α-Dystroglycan

Nakagawa¹,

Manya²,

Toda³

et al. 2012

“…Digestion of the 35 S-sulfated chondroitin product with chondroitinase AC I yielded a single peak that comigrated with D-glucono-4-enepyranoside ␤-1,3-GalNAc-4-SO 4 (Fig. 7).…”

Section: Chrondroitin-4-sulfotransferase-3mentioning

confidence: 99%

Molecular Cloning and Characterization of Chondroitin-4-O-sulfotransferase-3

Kang

Evers

Xia

et al. 2002

We have identified and characterized an N-acetylgalactosamine-4-O-sulfotransferase designated chondroitin-4-sulfotransferase-3 (C4ST-3) (GenBank TM accession number AY120869) based on its homology to HNK-1 sulfotransferase (HNK-1 ST). The cDNA predicts an open reading frame encoding a type II membrane protein of 341 amino acids with a 12-amino acid cytoplasmic domain and a 311-amino acid luminal domain containing a single potential N-linked glycosylation site. C4ST-3 has the greatest amino acid sequence identity when aligned with chondroitin-4-O-sulfotransferase 1 (C4ST-1) (45%) but also shows significant amino acid identity with chondroitin-4-O-sulfotransferase 2 (C4ST-2) (27%), dermatan-4-O-sulfotransferase 1 (29%), HNK-1 ST (26%), N-acetylgalactosamine-4-O-sulfotransferase 1 (26%), and N-acetylgalactosamine-4-Osulfotransferase 2 (23%). C4ST-3 transfers sulfate to the C-4 hydroxyl of ␤1,4-linked GalNAc that is substituted with a ␤-linked glucuronic acid at the C-3 hydroxyl. The open reading frame of C4ST-3 is encoded by three exons located on human chromosome 3q21.3. Northern blot analysis reveals a single 2.1-kilobase transcript. C4ST-3 message is expressed in adult liver and at lower levels in adult kidney, lymph nodes, and fetal liver. Although C4ST-3 and C4ST-1 have similar specificities, the highly restricted pattern of expression seen for C4ST-3 suggests that it has a different role than C4ST-1.We and others have recently reported the cloning and functional characterization of members of the HNK-1 family of sulfotransferases. These include human HNK-1 sulfotransferase (HNK-1 ST) 1 itself (1, 2), GalNAc-4-ST1 (3-5), GalNAc-4-ST2 (5, 6), dermatan-4-sulfotransferase-1 (D4ST-1) (7), chondroitin-4-sulfotransferase-1 (C4ST-1) (8, 9), and chondroitin-4-sulfotransferase-2 (C4ST-2) (8). With the exception of HNK-1 ST itself, which transfers sulfate to the C-3 hydroxyl of terminal glucuronic acid in the sequence GlcUA␤1,3Gal␤1,4GlcNAc-R to produce the HNK-1 epitope SO 4 -3-GlcUA␤1,3Gal␤1,4GlcNAc-R, the members of this family of sulfotransferases are all GalNAc-4-sulfotransferases. GalNAc-4-ST1 and GalNAc-4-ST2 both transfer sulfate to the C-4 hydroxyl of terminal ␤1,4-linked GalNAc on N-linked oligosaccharides such as those found on the glycoprotein hormones lutropin and thyrotropin (10, 11). Whereas C4ST-1, C4ST-2, and D4ST-1 are also GalNAc-4-O-sulfotransferases, they only transfer sulfate to the C-4 hydroxyl of internal ␤1,4-linked GalNAc moieties within the repeating disaccharide sequences found in chondroitin and dermatan (7-9). We now report the cloning of another member of this family of sulfotransferases. Like C4ST-1, this new sulfotransferase, chondroitin-4-sulfotransferase-3 (C4ST-3) transfers sulfate to the C-4 hydroxyl of ␤1,4-linked GalNAc that is flanked by GlcUA residues in chondroitin. In contrast to C4ST-1, C4ST-3 is labile at 37°C and has a restricted distribution, suggesting that it may have a unique biological role in vivo. EXPERIMENTAL PROCEDURES Molecular Cloning of a cDNA Encoding Human Chon...

“…In contrast to HNK-1 ST, GalNAc-4-ST1 transfers sulfate to the C-4 hydroxyl of ␤1,4-linked GalNAc on N-linked oligosaccharides such as those found on the glycoprotein hormones LH and TSH (24,25). Further screening of the EST database at GenBank TM , National Center for Biotechnology Information, using the deduced amino acid sequence of the catalytic domain of rat HNK-1 ST (GenBank TM accession number AF022729) identified the human EST H15485.…”

Section: Identification Of a Human Cdna Related To Hnk-1 St Andmentioning

confidence: 99%

“…C4ST-1 and C4ST-2 transfer sulfate to the C-4 hydroxyl of nonterminal ␤1,4-linked GalNAc in chondroitin and dermatan (22,23). GalNAc-4-ST1 transfers sulfate to the C-4 hydroxyl of terminal ␤1,4-linked GalNAc in the sequence GalNAc-␤1,4GlcNAc␤-R that is found on N-linked oligosaccharides (24,25).…”

mentioning

confidence: 99%

“…Despite the presence of these motifs, HNK-1 sulfotransferase shows only limited similarity to other sulfotransferases outside of the PAPS-binding regions. Nonetheless, three additional sulfotransferases, chondroitin 4-O-sulfotransferase 1 (C4ST-1) (22,23), chondroitin 4-O-sulfotransferase 2 (C4ST-2) (23), and N-acetylgalactosamine-4-O-sulfotransferase 1 (GalNAc-4-ST1) (24,25), were identified based on their homology to the catalytic C-terminal domain of HNK-1 ST. C4ST-1 and C4ST-2 ( Fig. 2) show 25 and 22% identity to HNK-1 ST, respectively, whereas GalNAc-4-ST1 is 23% identical to HNK-1 ST.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Molecular Cloning and Expression of anN-Acetylgalactosamine-4-O-sulfotransferase That Transfers Sulfate to Terminal and Non-terminal β1,4-LinkedN-Acetylgalactosamine

Kang

Evers²,

Xia³

et al. 2001

-7), and triggering preferential neurite outgrowth (8). HNK-1, an example of such a sulfated glycan, has the structure SO 4 -3-GlcUA␤1,3Gal␤1,4GlcNAc-R and is found at the nonreducing termini of glycoprotein and glycolipid oligosaccharides (9, 10). The structure was first identified with monoclonal antibodies as an epitope on human natural killer cells (11). The HNK-1 epitope is a hallmark of many neural recognition molecules and displays phylogenetic conservation (12), highlighting its functional importance. It is expressed in the central and peripheral nervous systems during development and regeneration (13,14) and has recently been recognized to be a crucial player in synaptic plasticity involving inhibitory interneurons in the hippocampus (15). HNK-1 is also a predominant autoantigen in demyelinating diseases of the peripheral nervous system (16).Expression cloning of the rat and human sulfotransferases responsible for synthesis of the HNK-1 epitope revealed the presence of two sequence motifs that are associated with 3Ј-phosphoadenosyl-5Ј-phosphosulfonate (PAPS) binding (17,18) and are common among all sulfotransferases cloned to date (19 -21). Despite the presence of these motifs, HNK-1 sulfotransferase shows only limited similarity to other sulfotransferases outside of the PAPS-binding regions. Nonetheless, three additional sulfotransferases, chondroitin 4-O-sulfotransferase 1 (C4ST-1) (22, 23), chondroitin 4-O-sulfotransferase 2 (C4ST-2) (23), and N-acetylgalactosamine-4-O-sulfotransferase 1 (GalNAc-4-ST1) (24, 25), were identified based on their homology to the catalytic C-terminal domain of HNK-1 ST. C4ST-1 and C4ST-2 (Fig. 2) show 25 and 22% identity to HNK-1 ST, respectively, whereas GalNAc-4-ST1 is 23% identical to HNK-1 ST. In addition to the motifs associated with binding PAPS, HNK-1 ST, C4ST-1, C4ST-2, and GalNAc-4-ST1 have three additional motifs of unknown function that are located C-terminal to the PAPS-binding motifs. While homolog-