Activation of the rat follicle-stimulating hormone receptor promoter by steroidogenic factor 1 is blocked by protein kinase a and requires upstream stimulatory factor binding to a proximal E box element.
The receptor for the pituitary glycoprotein hormone FSH (FSHR) and the nuclear hormone receptor steroidogenic factor 1 (SF-1) play important roles in control of the hypothalamic-pituitary- gonadal axis. FSHR is essential for integrating the pituitary FSH signal to gonadal response, while SF-1 is an important transcriptional regulator of many genes that function within this axis and is essential for the development of gonads and adrenal glands. Given the critical role of SF-1 in regulation of the gonads and the coexpression of FSHR and SF-1 in Sertoli and granulosa cells, we examined the ability of SF-1 to regulate transcription of the FSHR gene. We found that SF-1 stimulated rat FSHR promoter activity in a dose-dependent and promoter-specific manner. Examination of various promoter deletion mutants indicated that SF-1 acts through the proximal promoter region and upstream promoter sequences. An E box element within the proximal promoter is essential for activation of the FSHR promoter by SF-1. This element binds the transcriptional regulators USF1 and USF2 (upstream stimulatory factors 1 and 2) but not SF-1, as shown by electrophoretic mobility shift assays. In addition, functional studies identified a requirement for the USF proteins in SF-1 activation of FSHR and mapped an important regulatory domain within exons 4 and 5 of USF2. Cotransfection studies revealed that activation of protein kinase A leads to inhibition of SF-1-stimulated transcription of FSHR, while it synergized with SF-1 to activate the equine LH beta-promoter (ebeta). Thus, stimulation of the cAMP pathway differentially regulates SF-1 activation of the FSHR and ebeta-promoters.
Heckert
L L
LL
Department of Molecular and Integrative Physiology The University of Kansas Medical Center Kansas City, Kansas 66160, USA. lheckert@kumc.edu
D000818:Animals; D001483:Base Sequence; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology*; D015342:DNA Probes / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000502:physiology*; D004591:Electrophoresis, Polyacrylamide Gel; D051717:Fushi Tarazu Transcription Factors; D005786:Gene Expression Regulation / Q000502:physiology; D018398:Homeodomain Proteins; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic / Q000502:physiology*; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear; D011962:Receptors, FSH / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D054339:Steroidogenic Factor 1; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000502:physiology*; D015533:Transcriptional Activation / Q000502:physiology; D014162:Transfection; D014407:Tumor Cells, Cultured; D051720:Upstream Stimulatory Factors
D015342:DNA Probes; D004268:DNA-Binding Proteins; D051717:Fushi Tarazu Transcription Factors; D018398:Homeodomain Proteins; C515057:NR5A1 protein, human; D018160:Receptors, Cytoplasmic and Nuclear; D011962:Receptors, FSH; D054339:Steroidogenic Factor 1; D014157:Transcription Factors; C497181:USF1 protein, human; C497184:USF2 protein, human; D051720:Upstream Stimulatory Factors; C497183:Usf1 protein, mouse; C497182:Usf1 protein, rat; C497186:Usf2 protein, mouse; C497187:Usf2 protein, rat; C515058:steroidogenic factor 1, mouse; C515060:steroidogenic factor 1, rat; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases