Open AccessThe v-src inducible gene 9E3/pCEF4 is regulated by both its promoter upstream sequence and its 3' untranslated region.
Author(s) -
Gerd A. Blobel,
Hidesaburô Hanafusa
Publication year - 1991
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.88.4.1162
Subject(s) - rous sarcoma virus , microbiology and biotechnology , biology , untranslated region , reporter gene , promoter , gene , three prime untranslated region , gene expression , messenger rna , tata box , genetics
The 9E3/pCEF4 mRNA is strongly induced in Rous sarcoma virus-transformed chicken embryo fibroblasts when compared to untransformed cells. To identify cis-acting transcriptional elements that confer inducibility by v-src, we isolated the 9E3 promoter upstream region. We found that 1.53 kilobases upstream of the transcriptional start site, when placed in front of a reporter gene, conferred a small degree of inducibility by v-src, in both transient and stable transfections. Two potential AP-1 sites were identified in the 9E3 promoter. AP-1 elements have been implicated previously in mediating a transcriptional response to v-src in fibroblast cell lines. These elements alone do not confer a significant inducibility by v-src in primary chicken embryo fibroblasts. Since the 9E3 mRNA is stabilized in transformed cells, we replaced the 3' untranslated region of the reporter gene with the 9E3 3' untranslated region and found this construct to be strongly responsive to stimulation by v-src. In addition, the 9E3 3' untranslated region increased the response to serum and the tumor promoter phorbol 12-myristate 13-acetate. This suggests that a posttranscriptional mechanism plays a major role in the induction of 9E3 expression.