This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ohlsson, M Articles by Ny, T Search for Related Content PubMed PubMed Citation Articles by Ohlsson, M Articles by Ny, T

 Previous Article  |  Next Article 

Mol Cell Biol. 1993 January; 13(1): 266-275

Transcriptional regulation of the rat tissue type plasminogen activator gene: localization of DNA elements and nuclear factors mediating constitutive and cyclic AMP-induced expression.

Department of Applied Cell and Molecular Biology, University of Umeå, Sweden.

ABSTRACT

We have characterized tissue type plasminogen activator (tPA) promoter elements and nuclear factors required for follicle-stimulating hormone (FSH)-induced transcription of the rat tPA gene in granulosa cells and constitutive expression of the gene in the rat neuroblastoma cell line B103. Run-on transcription analysis of isolated nuclei revealed that B103 cells transcribe the tPA gene at a high and constitutive level, while FSH was found to induce tPA gene transcription in a rapid and transient manner in granulosa cells. The maximal FSH-induced transcription rate was obtained after 20 min and was similar in the absence or presence of the protein synthesis inhibitor cycloheximide. However, in the presence of cycloheximide, tPA transcription was not turned off but continued at a high rate for several hours. This phenomenon may at least partly explain the earlier finding that tPA mRNA is superinduced by FSH in the presence of cycloheximide. DNase I footprinting analysis of the first 621 bp of the tPA promoter revealed a total of six regions that interact with nuclear factors from B103 and granulosa cells. Deletion of the promoter region from positions -269 to -621, a region that includes the two most-upstream footprints, had no effect on constitutive or FSH-induced transcription in transient expression experiments. Nuclear extracts from both granulosa cells and B103 cells showed strong binding to a consensus cyclic AMP-responsive element (CRE) at positions -178 to -185 and a neighboring binding site for nuclear factor 1 (NF1) at positions -145 to -158. The factors binding to these two regions were identified as members of the CRE-binding protein and NF1 families of transcription factors, respectively. Footprints were also obtained over two GC boxes at positions -64 to -71 and -41 to -49. These footprints were more pronounced with nuclear extracts from B103 cells than with extracts from untreated or FSH-treated granulosa cells, but gel shift assays indicate that similar amounts of two distinct factors bind to the two GC boxes in both cell types. Transfection experiments using promoter constructs with inactivated promoter elements indicate that both the CRE and NF1 sites contribute to the FSH responsiveness of the rat tPA gene in granulosa cells, while only the NF1 site is important for constitutive expression in B103 cells. The two GC boxes were found to be necessary both for constitutive expression in B103 cells and for FSH-induced expression in granulosa cells, and inactivation of both GC boxes essentially eliminated the tPA promoter activity in both cell types.

This article has been cited by other articles:

• Pham, N.-L., Franzen, A., Levin, E. G. (2004). NF1 Regulatory Element Functions as a Repressor of Tissue Plasminogen Activator Expression. Arterioscler. Thromb. Vasc. Bio. 24: 982-987 [Abstract] [Full Text]  
• Apa, R., Lanzone, A., Miceli, F., Vaccari, S., Macchione, E., Stefanini, M., Canipari, R. (2002). Pituitary Adenylate Cyclase-Activating Polypeptide Modulates Plasminogen Activator Expression in Rat Granulosa Cell. Biol. Reprod. 66: 830-835 [Abstract] [Full Text]  
• Puri, S., Bansal, D. D., Uskokovic, M. R., MacGregor, R. R. (2000). Induction of tissue plasminogen activator secretion from rat heart microvascular cells by fM 1,25(OH)2D3. Am. J. Physiol. Endocrinol. Metab. 278: E293-E301 [Abstract] [Full Text]  
• Sumpio, B. E., Chang, R., Xu, W.-J., Wang, X.-J., Du, W. (1997). Regulation of tPA in endothelial cells exposed to cyclic strain: role of CRE, AP-2, and SSRE binding sites. Am. J. Physiol. Cell Physiol. 273: C1441-C1448 [Abstract] [Full Text]  
• Hardy, M. M., Feder, J., Wolfe, R. A., Bu, G. (1997). Low Density Lipoprotein Receptor-related Protein Modulates the Expression of Tissue-type Plasminogen Activator in Human Colon Fibroblasts. J. Biol. Chem. 272: 6812-6817 [Abstract] [Full Text]