title: DNA sequences required for expression of the LH beta promoter in primary cultures of rat pituitary cells.
abstract: To begin analysis of the DNA sequences necessary for luteinizing hormone (LH) gene transcription, fusion genes containing the 5' flanking region of the rat LH beta or the human alpha-subunit gene linked to luciferase were transfected into primary cultures of rat pituitary cells. The LH beta-luciferase construct was expressed in the primary cultures at a level 50 times greater than a promoterless luciferase control plasmid. Little or no expression of the LH beta-luciferase construct was detected following transfection of MCF-7, JAR or GH3 tumor cell lines. Treatment of transfected cells with gonadotropin-releasing hormone resulted in a modest induction of LH beta-luciferase activity. Considerably higher levels of LH beta-luciferase activity were obtained with cultures from ovariectomized rats than were obtained with cultures from intact female rats. Analysis of 5' deletions of the LH beta-luciferase construct demonstrated that activity was well maintained even after substantial deletions. The shortest construct, which contained 75 base pairs of 5' flanking sequence had 38% of the activity of the longest which contained 1.7 kilobase pairs of flanking sequence. These findings demonstrate that transfection of primary cultures of rat pituitary cells may provide a useful system for analysis of the cis-acting sequences and trans-acting factors required for LH gene expression.
authors.affiliation: Department of Physiology and Biophysics, University of Iowa, Iowa City 52242.
authors.forename: K E
authors.initials: KE
authors.lastname: Kim
authors.forename: K H
authors.initials: KH
authors.lastname: Day
authors.forename: P
authors.initials: P
authors.lastname: Howard
authors.forename: S R
authors.initials: SR
authors.lastname: Salton
authors.forename: J L
authors.initials: JL
authors.lastname: Roberts
authors.forename: R A
authors.initials: RA
authors.lastname: Maurer
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003001:Cloning, Molecular; D005260:Female; D005786:Gene Expression Regulation; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D007986:Luteinizing Hormone / Q000235:genetics* / Q000378:metabolism; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D051381:Rats; D012045:Regulatory Sequences, Nucleic Acid; D014162:Transfection
chemical_list: D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D008156:Luciferases