Translator Disclaimer
1 October 2003 Sp1 and Sp3 Are Important Regulators of AP-2γ Gene Transcription
Author Affiliations +
Abstract

AP-2γ is a member of the AP-2 transcription factor family, is highly enriched in the trophoblast cell lineage, and is essential for placental development. In an effort to identify factors regulating AP-2γ gene expression, we isolated and characterized the promoter and 5′-flanking region of the mouse and human AP-2γ genes. The transcription start site of the mouse AP-2γ gene was mapped by primer extension and 5′ rapid amplification of cDNA ends. Deletion analysis of the 5′-flanking region revealed a 704-base pair (bp) sequence located approximately 6 kilobases (kb) upstream of the transcription start site that is required for enhanced expression in trophoblast cells. Additional gene transfer studies showed that basal promoter activity resides within a highly conserved, approximately 200-bp DNA sequence located immediately upstream of the transcription start site. The conserved region is highly GC-rich and lacks typical TATA or CCAAT boxes. Multiple potential Sp- and AP-2-binding sites are clustered within this region. Electrophoretic mobility shift assays demonstrated that Sp1 and Sp3 bind to three sites in the promoter region of the mouse AP-2γ gene. Combined mutation of the three putative Sp sites reduced promoter activity by 80% in trophoblast and nontrophoblast cells, demonstrating the functional importance of these sites in regulating AP-2γ gene expression. In summary, we have identified a potential trophoblast cell-specific regulatory element located approximately 6 kb upstream of the murine AP-2γ gene transcription start site, and we have shown that Sp1 and Sp3 bind to cis-regulatory elements located in the promoter proximal region and contribute to basal promoter activity.

Mei Li and Rodney E. Kellems "Sp1 and Sp3 Are Important Regulators of AP-2γ Gene Transcription," Biology of Reproduction 69(4), 1220-1230, (1 October 2003). https://doi.org/10.1095/biolreprod.103.015545
Received: 21 January 2003; Accepted: 1 May 2003; Published: 1 October 2003
JOURNAL ARTICLE
11 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top