This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Borroni, R. Articles by Hinshelwood, M. M. Search for Related Content PubMed PubMed Citation Articles by Borroni, R. Articles by Hinshelwood, M. M.

A Putative Binding Site for Sp1 Is Involved in Transcriptional Regulation of CYP17 Gene Expression in Bovine Ovary¹

Cecil H. and Ida Green Center for Reproductive Biology Sciences and the Departments of Obstetrics/Gynecology and Biochemistry, University of Texas Southwestern Medical Center (R.B., Z.L., E.R.S., M.M.H.), Dallas, Texas 75235-9051; and the Department of Obstetrics and Gynecology, Clinica L. Mangiagalli, University of Milan (R.B.), Milan, Italy

Address all correspondence and requests for reprints to: Margaret M. Hinshelwood, Ph.D., Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75235-9051.

In the bovine ovary, thecal cells are the only cell type capable of expressing the CYP17 gene in response to LH. With the onset of ovulation and luteinization in the cow, there is complete loss of P450c17 expression. To characterize the molecular mechanisms involved in tissue-specific regulation of the CYP17 gene in the bovine ovary, deletion mutations of the bovine CYP17 promoter were ligated into a promoterless luciferase expression vector, and reporter constructs were transiently transfected into primary cultures of bovine thecal and luteal cells. Deletion of the promoter sequences between -191 and -101 bp dramatically decreased the levels of reporter gene activity in both thecal and luteal cells. Computer-assisted analysis revealed the presence of a putative inverted Sp1-like binding site at -188/-180 bp. Deletion or mutation of this sequence caused a decrease in both basal and forskolin-stimulated reporter gene activity. In addition, mutation or deletion of this sequence also decreased reporter gene expression induced by overexpression of the protein kinase A catalytic subunit. Electrophoretic mobility shift assays showed that this sequence binds to a nuclear protein(s) from both thecal and luteal cells that is related to Sp1, as suggested by the results of gel mobility supershift assay employing an antibody raised against Sp1. DNA-binding activity was not increased by the addition of forskolin to thecal or luteal cells. We conclude that this inverted Sp1-like binding sequence is involved in constitutive as well as cAMP-dependent expression of the CYP17 gene in the bovine ovary.

This article has been cited by other articles:

				A. J. Kuhl, S. M. Ross, and K. W. Gaido CCAAT/Enhancer Binding Protein {beta}, But Not Steroidogenic Factor-1, Modulates the Phthalate-Induced Dysregulation of Rat Fetal Testicular Steroidogenesis Endocrinology, December 1, 2007; 148(12): 5851 - 5864. [Abstract] [Full Text] [PDF]

				S. Natesampillai, M. E. Fernandez-Zapico, R. Urrutia, and J. D. Veldhuis A Novel Functional Interaction between the Sp1-like Protein KLF13 and SREBP-Sp1 Activation Complex Underlies Regulation of Low Density Lipoprotein Receptor Promoter Function J. Biol. Chem., February 10, 2006; 281(6): 3040 - 3047. [Abstract] [Full Text] [PDF]

				G. Zhang and J. D. Veldhuis Requirement for Proximal Putative Sp1 and AP-2 cis-Deoxyribonucleic Acid Elements in Mediating Basal and Luteinizing Hormone- and Insulin-Dependent in Vitro Transcriptional Activation of the CYP17 Gene in Porcine Theca Cells Endocrinology, June 1, 2004; 145(6): 2760 - 2766. [Abstract] [Full Text] [PDF]

				K. Reisinger, R. Kaufmann, and J. Gille Increased Sp1 phosphorylation as a mechanism of hepatocyte growth factor (HGF/SF)-induced vascular endothelial growth factor (VEGF/VPF) transcription J. Cell Sci., January 15, 2003; 116(2): 225 - 238. [Abstract] [Full Text] [PDF]

				M. Paciga, A. J. Watson, G. E. DiMattia, and G. F. Wagner Ovarian Stanniocalcin Is Structurally Unique in Mammals and Its Production and Release Are Regulated through the Luteinizing Hormone Receptor Endocrinology, October 1, 2002; 143(10): 3925 - 3934. [Abstract] [Full Text] [PDF]

				R. Bathgate, N. Moniac, B. Bartlick, M. Schumacher, M. Fields, and R. Ivell Expression and Regulation of Relaxin-Like Factor Gene Transcripts in the Bovine Ovary: Differentiation-Dependent Expression in Theca Cell Cultures Biol Reprod, October 1, 1999; 61(4): 1090 - 1098. [Abstract] [Full Text]

				P. Pena, A. T. Reutens, C. Albanese, M. D’Amico, G. Watanabe, A. Donner, I-W. Shu, T. Williams, and R. G. Pestell Activator Protein-2 Mediates Transcriptional Activation of the CYP11A1 Gene by Interaction with Sp1 Rather than Binding to DNA Mol. Endocrinol., August 1, 1999; 13(8): 1402 - 1416. [Abstract] [Full Text]

				X. Chu, C. J. Corbin, M. A. Kaminski, and A. J. Conley Unique Regulation of CYP17 Expression in the Trophectoderm of the Preattachment Porcine Blastocyst Endocrinology, February 1, 1999; 140(2): 632 - 640. [Abstract] [Full Text]