Heterodimer formation of cJun and ATF-2 is responsible for induction of c-jun by the 243 amino acid adenovirus E1A protein.

Abstract

The adenovirus E1A proteins differentially regulate AP‐1‐responsive genes. Collagenase and stromelysin are repressed by E1A, whereas the expression of c‐jun is elevated. Inhibition of collagenase has been found to be exerted through the consensus AP‐1 binding site TGAGTCA. Here we show that the distal AP‐1 binding site in the c‐jun promoter, the jun2TRE (TTACCTCA), is the decisive element of this promoter in mediating the positive response to the 243 amino acid E1A product. In vitro binding studies revealed that, in contrast to the consensus AP‐1 site which is preferentially targeted by dimers composed of the Jun and Fos families, the jun2TRE binds heterodimers composed of cJun and ATF‐2(‐like) proteins. Since stimulation of c‐jun transcription is a function of the transforming domain of E1A encoded by conserved region 1, cJun‐‐ATF‐2 may be one of the effector factors involved in transformation. The data further suggest that E1A can distinguish between cJun‐‐cJun and cJun‐‐ATF‐2 in imposing opposite states of activity.

Helicobacter pylori-Induced Invasion and Angiogenesis of Gastric Cells Is Mediated by Cyclooxygenase-2 Induction through TLR2/TLR9 and Promoter Regulation

“…Our finding provided evidence for an alternative mechanism whereby CREB was phosphorylated by MAPKs as found by Yu et al (51). ATF-2 has been reported to be activated by JNK and p38 (52,53). In this study, we showed that ATF-2 was activated by all three MAPKs.…”

The Jun Kinase/Stress-activated Protein Kinase Pathway Functions to Regulate DNA Repair and Inhibition of the Pathway Sensitizes Tumor Cells to Cisplatin

“…Expression of dnJun has no effect on either basal AP-1 activity (1, 2) or on the enzyme activity of JNK (data not shown) but does inhibit phosphorylation-dependent activation of transcription (1,2,10,12). The effect of cisplatin treatment on the viability of representative clonal lines of the dnJun-expressing T98G cells is compared with that of an empty vector control line, T98GLHCX, in Fig.…”

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ATF-2 Regulates Fat Metabolism inDrosophila

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