title: Transcriptional activity of the 5' upstream region of the porcine glycoprotein hormone alpha subunit gene.
abstract: Gene expression of the porcine glycoprotein hormone alpha subunit (p-alphaGSU) was examined in LbetaT2 cells, which were established from the anterior pituitary lobe of the immortalized transgenic mouse and produce alphaGSU, and in CHO cells cloned from Chinese hamster ovaries. Expression of the reporter gene fused with p-alphaGSU gene upstream in LbetaT2 cells showed that the distal regions -540/-240 and -798/-541 are important for the activation of gene expression. In contrast, the transcriptional activity of the distal region of p-alphaGSU gene was repressed in CHO cells. The region -540/-240 contains an adequate enhancer, called pituitary glycoprotein hormone basal element, whereas the region -798/-541 has no distinguished element. Transfection of the expression vector containing cDNA of a pan-pituitary activator, Ptx1, whose putative binding sites are present scatted in the distal region of the p-alphaGSU gene, revealed unexpectedly that this factor significantly suppressed the expression of p-alphaGSU gene in LbetaT2 cells, indicating that Ptx1 is unrelated to the upregulation in the region -798/-541. Thus, this study demonstrated for the first time that the distal region -798/-541of the p-alphaGSU gene is indispensable for prominent expression of this gene in which an as yet unidentified factor may participate.
authors.affiliation: Laboratory of Molecular Biology and Gene Regulation, Department of Life Science, School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Aikawa
authors.forename: Takao
authors.initials: T
authors.lastname: Susa
authors.forename: Takanobu
authors.initials: T
authors.lastname: Sato
authors.forename: Kousuke
authors.initials: K
authors.lastname: Kitahara
authors.forename: Takako
authors.initials: T
authors.lastname: Kato
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kato
mesh_terms: D000818:Animals; D001665:Binding Sites; D016466:CHO Cells; D006224:Cricetinae; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D005822:Genetic Vectors; D015292:Glycoprotein Hormones, alpha Subunit / Q000096:biosynthesis* / Q000235:genetics*; D006023:Glycoproteins / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism; D051761:Paired Box Transcription Factors; D010902:Pituitary Gland / Q000378:metabolism; D011401:Promoter Regions, Genetic; D013552:Swine; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D015292:Glycoprotein Hormones, alpha Subunit; D006023:Glycoproteins; D018398:Homeodomain Proteins; D051761:Paired Box Transcription Factors; D014157:Transcription Factors; C101485:homeobox protein PITX1