Showing papers by "Shogo Oka published in 2002"
TL;DR: It is shown that the loss of a single non-reducing terminal carbohydrate residue attenuates brain higher functions in mice generated with a targeted deletion of the GlcAT-P gene.
138 citations
TL;DR: Transient transfection of luciferase reporter constructs demonstrated that a 207 bp fragment of the 5'-upstream region acts as a strong promoter in PC-12 cells, which express the HNK-1 epitope, but not in COS-1 cells, Thus, this minimal promoter region of GlcAT-P is suggested to be associated with the regulation of H NK-1 expression.
Abstract: cDNA and genomic clones encoding the mouse glucuronyltransferase (GlcAT-P) involved in biosynthesis of the HNK-1 carbohydrate epitope were isolated and the structural organization of the gene was determined. The predicted amino acid sequence of mouse GlcAT-P is 96.2 and 98.2% identical to those of the rat and human enzymes, respectively. Alternatively spliced isoforms of mouse GlcAT-P are present in the brain and encode two proteins that are identical throughout their length except for an additional 13 amino acids in the N-terminal cytoplasmic domain of the major form. The coding region of GlcAT-P is composed of 5 exons spanning approximately 6 kb, and the GlcAT-P gene was mapped to the A4 region of mouse chromosome 9. Upstream of the transcriptional start site, no typical TATA or CCAAT box was found, but binding sites for several known transcription factors including Sp1 and Krox-20 were identified. Transient transfection of luciferase reporter constructs demonstrated that a 207 bp fragment of the 5'-upstream region acts as a strong promoter in PC-12 cells, which express the HNK-1 epitope, but not in COS-1 cells. Thus, this minimal promoter region of GlcAT-P is suggested to be associated with the regulation of HNK-1 expression.
20 citations
TL;DR: The HNK-1 carbohydrate epitope is expressed on a series of cell adhesion molecules and some glycolipids in the nervous system and the mouse GlcAT-S gene is a single copy gene and it was mapped to the A4-B region of mouse chromosome 1.
15 citations
01 Jan 2002
TL;DR: Leading lines of evidence indicate that the HNK-1 epitope plays important roles in cell-cell and cell-substrate interaction during development ot the nervous system.
Abstract: The HNK-1 carbohydrate epitope, recognized by the monoclonal antibody HNK-1 (Abo and Balch 1981), is characteristically expressed on a series of cell adhesion molecules, including neural cell adhesion molecule (NCAM), myelin-associated glycoprotein (MAG), L1, PO, telencephalin, and others (McGarry et al. 1983; Kruse et al. 1984; Bollensen and Schachner 1987; Yoshihara et al. 1994), and on some glycolipids (Ilyas et al. 1984) in the nervous system. The HNK-1 epitope is spatially and temporally regulated during development of the nervous system (Schwarting et al. 1987); and characteristic expression of this epitope is observed in migrating neural crest cells (Bronner-Fraser 1986),rhombomeres (Kuratani 1991), and cerebellum (Eisenman and Hawkes 1993). The structure of the HNK-1 epitope is demonstrated to be the sulfated trisaccharide SO4-3GlcAβ1-3Galβ1-4GlcNAc, which is shared with glycolipid and glycoprotein epitope (Chou et al. 1986; Ariga et al. 1987; Voshol et al. 1996). The HNK-1 epitope associates with neural crest cell migration (Bronner-Fraser 1987), neuron to glial cell adhesion (Keilhauer et al. 1985), outgrowth of astrocytic processes and migration of the cell body (Kunemund et al. 1988), as well as the preferential outgrowth of neurites from motor neurons (Martini et al. 1992). These lines of evidence indicate that the HNK-1 epitope plays important roles in cell-cell and cell-substrate interaction during development ot the nervous system.