Transcriptional regulation of human Galbeta1,3GalNAc/Galbeta1, 4GlcNAc alpha2,3-sialyltransferase (hST3Gal IV) gene in testis and ovary cell lines.
The mRNA expression of sialyltransferase genes is regulated in a cell-type-specific manner. The mRNAs of human Galbeta1, 3GalNAc/Galbeta1, 4 GlcNAc alpha2,3-sialyltransferase gene (hST3Gal IV) consist of six isoforms, type A1, A2, B1, B2, B3, and BX. These mRNAs are transcribed from different promoters, pA, pB1, pB2, pB3, and pBX, respectively. Type B mRNAs are expressed in several cells, whereas type A mRNAs are specifically expressed in testis, ovary, and placenta, suggesting that pA promoter activity is especially high in these tissues. We show herein germ-cell specific transcriptional regulation of the hST3Gal IV pA promoter. Using a luciferase assay, pA promoter activity is shown to be high in testis and ovary cell lines. We identified the enhancer region of the pA promoter, located at nt -520 to -420. These results suggest that this element plays a critical role in germ-cell specific regulation of the pA promoter. The results of site-directed mutagenesis suggest that AP2 and c-Ets sites in this region are involved in pA promoter activity, which in turn suggests that the hST3Gal IV gene is regulated in a tissue-restricted fashion at the level of transcription.
Taniguchi
Akiyoshi
A
Bionic Materials Group, Biomaterials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, Japan. taniguchi.akiyoshi@nims.go.jp
Hioki
Maiko
M
Matsumoto
Kojiro
K
D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D005260:Female; D006801:Humans; D008297:Male; D009154:Mutation; D010053:Ovary / Q000201:enzymology*; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D050783:Proto-Oncogene Proteins c-ets; D012799:Sialyltransferases / Q000235:genetics*; D013737:Testis / Q000201:enzymology*; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase
D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D050656:Transcription Factor AP-2; D014157:Transcription Factors; D012799:Sialyltransferases; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase; C000722087:ST3GAL1 protein, human