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Featured researches published by Hiroko Habuchi.


Journal of Biological Chemistry | 2000

The Occurrence of Three Isoforms of Heparan Sulfate 6-O-Sulfotransferase Having Different Specificities for Hexuronic Acid Adjacent to the TargetedN-Sulfoglucosamine

Hiroko Habuchi; Masayuki Tanaka; Osami Habuchi; Keiichi Yoshida; Hiroaki Suzuki; Kazuhiko Ban; Koji Kimata

We previously cloned heparan sulfate 6-O-sulfotransferase (HS6ST) (Habuchi, H., Kobayashi, M., and Kimata, K. (1998) J. Biol. Chem. 273, 9208–9213). In this study, we report the cloning and characterization of three mouse isoforms of HS6ST, a mouse homologue to the original human HS6ST (HS6ST-1) and two novel HS6STs (HS6ST-2 and HS6ST-3). The cDNAs have been obtained from mouse brain cDNA library by cross-hybridization with human HS6ST cDNA. The three cDNAs contained single open reading frames that predicted type II transmembrane proteins composed of 401, 506, and 470 amino acid residues, respectively. Amino acid sequence of HS6ST-1 was 51 and 57% identical to those of HS6ST-2 and HS6ST-3, respectively. HS6ST-2 and HS6ST-3 had the 50% identity. Overexpression of each isoform in COS-7 cells resulted in about 10-fold increase of HS6ST activity. The three isoforms purified with anti-FLAG antibody affinity column transferred sulfate to heparan sulfate and heparin but not to other glycosaminoglycans. Each isoform showed different specificity toward the isomeric hexuronic acid adjacent to the targetedN-sulfoglucosamine; HS6ST-1 appeared to prefer the iduronosyl N-sulfoglucosamine while HS6ST-2 had a different preference, depending upon the substrate concentrations, and HS6ST-3 acted on either substrate. Northern analysis showed that the expression of each message in various tissues was characteristic to the respective isoform. HS6ST-1 was expressed strongly in liver, and HS6ST-2 was expressed mainly in brain and spleen. In contrast, HS6ST-3 was expressed rather ubiquitously. These results suggest that the expression of these isoforms may be regulated in tissue-specific manners and that each isoform may be involved in the synthesis of heparan sulfates with tissue-specific structures and functions.


Journal of Biological Chemistry | 1997

Turnover of Heparan Sulfate Depends on 2-O-Sulfation of Uronic Acids

Xiaomei Bai; Karen J. Bame; Hiroko Habuchi; Koji Kimata; Jeffrey D. Esko

To study how the pattern of sulfation along a heparan sulfate chain affects its turnover, we examined heparan sulfate catabolism in wild-type Chinese hamster ovary cells and mutant pgsF-17, defective in 2-O-sulfation of uronic acid residues (Bai, X., and Esko, J. D. (1996) J. Biol. Chem. 271, 17711–17717). Heparan sulfate from the mutant contains normal amounts of 6-O-sulfated glucosamine residues and iduronic acid and somewhat higher levels of N-sulfated glucosamine residues but lacks any 2-O-sulfated iduronic or glucuronic acid residues. Pulse-chase experiments showed that both mutant and wild-type cells transport newly synthesized heparan sulfate proteoglycans to the plasma membrane, where they shed into the medium or move into the cell through endocytosis. Internalization of the cell-associated molecules leads to sequential endoglycosidase (heparanase) fragmentation of the chains and eventual lysosomal degradation. In wild-type cells, the chains begin to degrade within 1 h, leading to the accumulation of intermediate (10–20-kDa) and small (4–7-kDa) oligosaccharides. Mutant cells did not generate these intermediates, although internalization and intracellular trafficking of the heparan sulfate chains appeared normal, and the chains degraded with normal kinetics. This difference was not due to defective heparanase activities in the mutant, since cytoplasmic extracts from mutant cells cleaved wild-type heparan sulfate chains in vitro. Instead, the heparan sulfate chains from the mutant were relatively resistant to degradation by cellular heparanases. These findings suggest that 2-O-sulfated iduronic acid residues in heparan sulfate are important for cleavage by endogenous heparanases but not for the overall catabolism of the chains.


Journal of Biological Chemistry | 1997

Molecular Cloning and Expression of Chinese Hamster Ovary Cell Heparan-sulfate 2-Sulfotransferase

Masashi Kobayashi; Hiroko Habuchi; Masahiko Yoneda; Osami Habuchi; Koji Kimata


Journal of Biological Chemistry | 2001

Drosophila heparan sulfate 6-O-sulfotransferase (dHS6ST) gene: Structure, expression, and function in the formation of the tracheal system

Keisuke Kamimura; Momoko Fujise; Francisco Villa; Susumu Izumi; Hiroko Habuchi; Koji Kimata; Hiroshi Nakato


Journal of Biological Chemistry | 2000

Molecular Cloning and Expression of Chondroitin 4-Sulfotransferase

Shinobu Yamauchi; Satoka Mita; Taeko Matsubara; Masakazu Fukuta; Hiroko Habuchi; Koji Kimata; Osami Habuchi


Journal of Biological Chemistry | 1986

Changes in proteoglycan composition during development of rat skin. The occurrence in fetal skin of a chondroitin sulfate proteoglycan with high turnover rate.

Hiroko Habuchi; Koji Kimata; Sakaru Suzuki


Glycobiology | 2002

Effects of chemically modified heparin on Chlamydia trachomatis serovar L2 infection of eukaryotic cells in culture

Hiromitsu Yabushita; Yasuyuki Noguchi; Hiroko Habuchi; Satoko Ashikari; Ken Nakabe; Masaru Fujita; Masayoshi Noguchi; Jeffrey D. Esko; Koji Kimata


Archive | 1992

Oligosaccharide having affinity for fibroblast growth factor and process for producing same

Hiroko Habuchi; Sakaru Suzuki; Koji Kimata


Archive | 2001

Sulfate transferase and DNA encoding this enzyme

Hiroko Habuchi; Koji Kimata


Archive | 2006

Sulfotransferase and DNA encoding the enzyme

Hiroko Habuchi; Koji Kimata

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Osami Habuchi

Aichi University of Education

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Sakaru Suzuki

Aichi Medical University

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Masashi Kobayashi

Aichi University of Education

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