Cloning and characterization of the human oviduct-specific glycoprotein (HuOGP) gene promoter.
Oviduct-specific glycoprotein (OGP) is a high molecular weight glycoprotein belonging to the chitinase protein family. OGPs are found to associate with the zona pellucida and plasma membrane of the oocyte and developing embryo. Recent studies have shown that OGP plays an important role in pre-fertilization reproductive events (i.e. sperm capacitation, sperm-zona binding and zona penetration). To have a better understanding of human OGP (HuOGP) gene expression, a 3.3 kb DNA fragment containing the 5'-flanking and the intron I region of the HuOGP gene was isolated. DNA sequence analysis of the HuOGP putative promoter revealed little homology with its hamster and mouse ogp gene counterparts. One transcription initiation site was found 12 nucleotides upstream of the first ATG codon of the HuOGP gene. The HuOGP gene promoter lacked typical CAAT or GC boxes, but contained eight half estrogen-responsive elements (ERE) and an imperfect ERE (iERE; 5'-GGTCANNNTGACT-3') site. Deletion mutants of the 3.3 kb DNA fragment were generated and fused to a promoterless beta-galactosidase (beta-Gal) gene. Transfection studies revealed that in the presence of 100 nmol/l estradiol-17 beta (E(2)), a minimal 0.3 kb promoter construct (pH-298/+25 beta Gal) mediated a high level of beta-Gal expression in immortalized human oviductal epithelial OE-E6/E7 cells, but not in MCF-7 and CHO-K1 cells. By electromobility shift assay and specific estrogen receptor antibodies, we demonstrated that estrogen receptor beta present in the OE-E6/E7 cells binds to the iERE. These findings allow a better understanding of the regulation of OGP gene expression in the human oviduct.
Agarwal
Anika
A
Department of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, People's Republic of China.
Yeung
William S B
WS
Lee
Kai-Fai
KF
D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D002478:Cells, Cultured; D003001:Cloning, Molecular; D006224:Cricetinae; D004247:DNA; D004967:Estrogens / Q000502:physiology; D005187:Fallopian Tubes / Q000502:physiology; D005260:Female; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA
D004967:Estrogens; D006023:Glycoproteins; C091468:OVGP1 protein, human; D004247:DNA