Transcriptional regulation of human beta-galactoside alpha2, 6-sialyltransferase (hST6Gal I) gene during differentiation of the HL-60 cell line.
We have previously shown that the expression of beta-galactoside alpha2,6-sialyltransferase (hST6Gal I) mRNA decreases during HL-60 differentiation induced with dimethyl sulfoxide (DMSO) and that transcriptional regulation depends on the P3 promoter that exists 5'-upstream of exon Y (A. Taniguchi et al., FEBS Lett.,441, 191-194, 1998). The regulation of hST6Gal I may be important for the expression of sialyl-Le(x)in HL-60 cells. In the present report, we studied the transcriptional regulation of hST6Gal I gene during DMSO-induced differentiation of HL-60 cells. To elucidate the molecular basis of hST6Gal I gene expression, the genomic region containing the P3 promoter of hST6Gal I was isolated and functionally characterized. Using a luciferase assay, we identified a functional DNA portion that confers an enhancer, located at nucleotide number (nt) -317 to -174 within the P3 promoter of hST6Gal I genomic DNA. This element contains two sequences similar to Sp1 (GC-box) and one sequence similar to Oct-1 recognition motifs (octamer sequence). Site-directed mutagenesis of Sp1 and Oct-1 sites showed that two Sp1 motifs and one Oct-1 motif are essential for transcriptional activity in HL-60 cells. Enhancer activity is suppressed during HL-60 cell differentiation induced with DMSO. These results suggest that GC-box and octamer sequence may play a critical role in the transcriptional regulation of the hST6Gal I gene during HL-60 cell differentiation.
Taniguchi
A
A
Department of Clinical Chemistry, School of Pharmaceutical Sciences, Toho University, Chiba, Japan.
Hasegawa
Y
Y
Higai
K
K
Matsumoto
K
K
D001483:Base Sequence; D001665:Binding Sites; D002454:Cell Differentiation / Q000187:drug effects; D004247:DNA / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D018922:HL-60 Cells; D051863:Host Cell Factor C1; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D050811:Octamer Transcription Factor-1; D011401:Promoter Regions, Genetic; D012799:Sialyltransferases / Q000737:chemistry / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase
D004268:DNA-Binding Proteins; C497692:HCFC1 protein, human; D051863:Host Cell Factor C1; D050811:Octamer Transcription Factor-1; C494165:POU2F1 protein, human; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D004247:DNA; D012799:Sialyltransferases; D004121:Dimethyl Sulfoxide; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase