Steroidogenic factor-1 is an essential transcriptional activator for gonad-specific expression of promoter I of the rat prolactin receptor gene.
The expression of the prolactin receptor is under the control of two putative tissue-specific (PI, gonads; PII, liver) and one common (PIII) promoters (Hu, Z. Z., Zhuang, L., and Dufau, M. L. (1996) J. Biol. Chem. 271, 10242-10246). The three promoter regions were co-localized to the rat chromosomal locus 2ql6, in the order 5'-PIII-PI-PII-3'. To investigate the mechanisms of gonad-specific utilization of PI, the promoter domain, regulatory cis-elements, and trans-factors were identified in gonadal cells. The promoter domain localized to the 152-base pair 5' of the transcriptional start site at -549 is highly active in gonadal cells but has minimal activity in hepatoma cells. It contains a steroidogenic factor 1 (SF-1) element (-668) that binds the SF-1 protein of nuclear extracts from gonadal cells and is essential for promoter activation. A CCAAT box (-623) contributes minimally to basal activity in the absence of the SF-1 element, and two adjacent TATA-like sequences act as inhibitory elements. Thus, PI belongs to a class of TATA-less/non-initiator gene promoters. These findings demonstrate an essential role for SF-1 in transcriptional activation of promoter I of the prolactin receptor gene, which may explain the tissue-specific expression of PI in the gonads but not in the liver and the mammary gland.
Hu
Z
Z
Section on Molecular Endocrinology, Endocrinology and Reproduction Research Branch, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA.
Zhuang
L
L
Guan
X
X
Meng
J
J
Dufau
M L
ML
D000818:Animals; D002478:Cells, Cultured; D002874:Chromosome Mapping; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D051717:Fushi Tarazu Transcription Factors; D005786:Gene Expression Regulation; D018398:Homeodomain Proteins; D008297:Male; D051379:Mice; D009928:Organ Specificity; D010053:Ovary / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018160:Receptors, Cytoplasmic and Nuclear; D011981:Receptors, Prolactin / Q000235:genetics* / Q000378:metabolism; D054339:Steroidogenic Factor 1; D013737:Testis / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D004268:DNA-Binding Proteins; D051717:Fushi Tarazu Transcription Factors; D018398:Homeodomain Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D011981:Receptors, Prolactin; D054339:Steroidogenic Factor 1; D015534:Trans-Activators; D014157:Transcription Factors; C515058:steroidogenic factor 1, mouse; C515060:steroidogenic factor 1, rat