v-src induction of the TIS10/PGS2 prostaglandin synthase gene is mediated by an ATF/CRE transcription response element.

Abstract

We recently reported the cloning of a mitogen-inducible prostaglandin synthase gene, TIS10/PGS2. In addition to growth factors and tumor promoters, the v-src oncogene induces TIS10/PGS2 expression in 3T3 cells. Deletion analysis, using luciferase reporters, identifies a region between -80 and -40 nucleotides 5' of the TIS10/PGS2 transcription start site that mediates pp6Wvsrc induction in 3T3 cells. This region contains the sequence CGTCACGTG, which includes overlapping ATF/CRE (CGTCA) and E-box (CACGTG) sequences. Gel shift-oligonucleotide competition experiments with nuclear extracts from cells stably transfected with a temperature-sensitive v-src gene demonstrate that the CGTCACGTG sequence can bind proteins at both the ATF/CRE and E-box sequences. Dominant-negative CREB and Myc proteins that bind DNA, but do not transactivate, block v-src induction of a luciferase reporter driven by the first 80 nucleotides of the TIS10/PGS2 promoter. Mutational analysis distinguishes which TIS10/PGS2 cis-acting element mediates pp60v' induction. E-box mutation has no effect on the fold induction in response to pp60VW . In contrast, ATF/CRE mutation attenuates the pp60V' response. Antibody supershift and methylation interference experiments demonstrate that CREB and at least one other ATF transcription factor in these extracts bind to the TIS1O/PGS2 ATF/CRE element. Expression of a dominant-negative ras gene also blocks TIS10/PGS2 induction by v-src. Our data suggest that Ras mediates pp60V' activation of an ATF transcription factor, leading to induced TIS10/PGS2 expression via the ATF/CRE element of the TIS10/PGS2 promoter. This is the first description of v-src activation of gene expression via an ATF/CRE element.

Bradykinin B2 Receptor Mediates NF-κB Activation and Cyclooxygenase-2 Expression via the Ras/Raf-1/ERK Pathway in Human Airway Epithelial Cells

“…Ras might activate a number of signal pathways, including the Raf-1/MEK/ERK pathway and the PI3K/ Akt/NF-B pathway (26,51,52). In murine fibroblasts, activation of the Ras/Raf-1/ERK1/2 signal pathway is required for COX-2 induction (50). In this study, we found that treatment of A549 cells with BK caused subsequent activation of Ras, Raf-1, and ERK, and that manumycin A, GW 5074, and PD 098059 all inhibited BK-induced ERK activation and COX-2 expression.…”

“…Ras, an oncogenic protein, plays a critical role in inducing COX-2 expression (49,50). Ras might activate a number of signal pathways, including the Raf-1/MEK/ERK pathway and the PI3K/ Akt/NF-B pathway (26,51,52).…”

The constitutive activation of the CEF-4/9E3 chemokine gene depends on C/EBPβ in v-src transformed chicken embryo fibroblasts

“…Since the e ects of D184-C/EBPb were transient in CEF and only observed in the ®rst hour following the activation of the thermolabile by pp60 v-src , this may explain why C/EBPb has not been identi®ed previously as a critical factor in the v-src dependent activation of this gene. Factors targeting the CRE are involved in the activation of Cox-2 by pp60 v-src in murine ®broblasts (Xie et al, 1994).…”

Cyclosporine A Suppresses Cyclooxygenase-2 Expression in the Rat Kidney

“…In brief, cDNA probes were synthesized in a 20-l reaction with 2 g of total RNA, 0.5 g of oligo(dT) [12][13][14][15][16][17][18] , 20 U of RNasin (Promega, Madison, WI), 4 l of 5ϫ RT Buffer, 0.5 mM dNTP, and 20 U of M-MLV reverse transcriptase enzyme (Life Technologies, Gaithersburg, MD).…”

“…Preliminary evidence has been elaborated for possible involvements of the MAP-kinase and NF-B pathways (9 -11). In fact, the COX-2 gene promoter contains, apart from a classical TATA box, an E-box and a CRE-element, both representing binding sites for transcription factors such as NF-B (12)(13)(14)(15). A series of recent reports has provided evidence that the COX-2 promoter also contains binding sites for the nuclear factor of activated T cells (NFAT) (16 -19) and that activation of this factor stimulates COX-2 expression in several cell lines (16 -19).…”