Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05412 (c-Jun)
 11,453 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

p53 phosphorylation and association with proteins is implicated in its stability and activity. We have compared the association of DNA-bound and overall pools of p53 with murine double minute 2 (Mdm2), c-Jun NH2-terminal kinase (JNK), p300/CBP, and p14ARF during cell cycle progression. Whereas DNA-bound p53 associates with JNK at G0-G1 and with Mdm2 and p300 during S and G2-M phases, the general pool of p53 was found in complex with JNK and Mdm2 almost throughout the cell cycle. Phosphorylation of p53 at serines 9, 15, and 20 is at the highest levels at G1 and at serines 37 and 392 during G2-M phase. Whereas a high dose of UV irradiation was required for phosphorylation of serines 15 and 392 between 8 and 24 h after treatment, a low dose caused immediate phosphorylation on serines 9, 20, and 372. These dynamic changes in the phosphorylation of p53 are expected to play a pivotal role in p53 association, stability, and function.
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PMID:p53 phosphorylation and association with murine double minute 2, c-Jun NH2-terminal kinase, p14ARF, and p300/CBP during the cell cycle and after exposure to ultraviolet irradiation. 1070 2

The interaction of transcription factors is critical in the regulation of gene expression. This study characterized the mechanism by which NF-kappa B family members interact to regulate the human TNF-alpha gene. A 120-bp TNF-alpha promoter-reporter, possessing binding sites for NF-kappa B (kappa B3), C/EBP beta (CCAAT/enhancer binding protein beta), and c-Jun, was activated by cotransfection of plasmids expressing the wild-type version of each of these transcription factors. Employing adenoviral vectors, dominant-negative versions of NF-kappa B p65, and c-Jun, but not C/EBP beta, suppressed (p < 0.05-0.001) LPS-induced TNF-alpha secretion in primary human macrophages. Following LPS stimulation, NF-kappa B p50/p65 heterodimers bound to the kappa B3 site and c-Jun to the -103 AP-1 site of the TNF-alpha promoter. By transient transfection, NF-kappa B p65 and p50 synergistically activated the TNF-alpha promoter. In contrast, no synergy was observed between NF-kappa B p65, with or without NF-kappa B p50, and c-Jun or C/EBP beta, even in the presence of the coactivator p300. The contribution of the upstream kappa B binding sites was also examined. Following LPS stimulation, the kappa B1 site bound both NF-kappa B p50/p65 heterodimers and p50 homodimers. The binding by NF-kappa B p50 homodimers to the kappa B1, but not to the kappa 3, site contributed to the inability of macrophages to respond to a second LPS challenge. In summary, adjacent kappa B3 and AP-1 sites in the human TNF-alpha promoter contribute independently to LPS-induced activation. Although both the kappa B1 and kappa B3 sites bound transcriptionally active NF-kappa B p50/p65 heterodimers, only the kappa B1 site contributed to down-regulation by NF-kappa B p50 homodimers.
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PMID:TNF-alpha gene expression in macrophages: regulation by NF-kappa B is independent of c-Jun or C/EBP beta. 1075 26

ASC-2 was recently discovered as a cancer-amplified transcription coactivator molecule of nuclear receptors, which interacts with multifunctional transcription integrators steroid receptor coactivator-1 (SRC-1) and CREB-binding protein (CBP)/p300. Herein, we report the identification of three mitogenic transcription factors as novel target molecules of ASC-2. First, the C-terminal transactivation domain of serum response factor (SRF) was identified among a series of ASC-2-interacting proteins from the yeast two-hybrid screening. Second, ASC-2 specifically interacted with the activating protein-1 (AP-1) components c-Jun and c-Fos as well as the nuclear factor-kappaB (NFkappaB) components p50 and p65, as demonstrated by the glutathione S-transferase pull-down assays as well as the yeast two-hybrid tests. In cotransfection of mammalian cells, ASC-2 potentiated transactivations by SRF, AP-1, and NFkappaB in a dose-dependent manner, either alone or in conjunction with SRC-1 and p300. In addition, ASC-2 efficiently relieved the previously described transrepression between nuclear receptors and either AP-1 or NFkappaB. Overall, these results suggest that the nuclear receptor coactivator ASC-2 also mediates transactivations by SRF, AP-1, and NFkappaB, which may contribute to the putative, ASC-2-mediated tumorigenesis.
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PMID:Activating protein-1, nuclear factor-kappaB, and serum response factor as novel target molecules of the cancer-amplified transcription coactivator ASC-2. 1084 92

Understanding the molecular mechanisms underlying the antagonistic activities of tumor necrosis factor-alpha (TNF-alpha) against transforming growth factor-beta (TGF-beta) is of utmost importance given the physiopathological implications of these cytokines. In this report, we demonstrate that TNF-alpha prevents TGF-beta-induced Smad-specific gene transactivation without inducing detectable levels of inhibitory Smad7 in human dermal fibroblasts. On the other hand, c-Jun and JunB, both induced by TNF-alpha, block Smad3-mediated transcription. Expression of antisense c-Jun mRNA prevents TNF-alpha inhibition of TGF-beta/Smad signaling whereas that of dominant-negative Ikappa-B kinase-alpha or antisense Smad7 does not. We provide evidence for off-DNA interactions between Smad3 and both c-Jun and JunB accompanied with reduced Smad3-DNA interactions. Finally, we show that overexpression of the transcriptional co-activator p300 prevents TNF-alpha/AP-1 inhibition of TGF-beta/Smad signaling. These data suggest that TNF-alpha interferes with Smad signaling through the induction of AP-1 components, the latter forming off-DNA complexes with Smad3 and preventing its binding to specific cis-element(s). In addition, Jun members compete with Smad3 for the common transcription co-activator p300. These two mechanisms are likely to act in concert to decrease Smad-specific transcription.
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PMID:Tumor necrosis factor-alpha inhibits transforming growth factor-beta /Smad signaling in human dermal fibroblasts via AP-1 activation. 1090 23

Deletion analysis of the human PRL promoter in endometrial stromal cells decidualized in vitro revealed a 536-bp enhancer located between nucleotide (nt) -2,040 to -1,505 in the 5'-flanking region. The 536-bp enhancer fragment ligated into a thymidine kinase (TK) promoter-luciferase reporter plasmid conferred enhancer activity in decidual-type cells but not nondecidual cells. DNase I footprint analysis of decidualized endometrial stromal cells revealed three protected regions, FP1-FP3. Transfection of overlapping 100-bp fragments of the 536-bp enhancer indicated that FP1 and FP3 each conferred enhancer activity. Gel shift assays indicated that both FP1 and FP3 bind activator protein 1 (AP-1), and JunD and Fra-2 are components of the AP-1 complex in decidual fibroblasts. Mutation of the AP-1 binding site in either FP1 or FP3 decreased enhancer activity by approximately 50%, while mutation of both sites almost completely abolished activity. Coexpression of the 536-bp enhancer and A-fos, a dominant negative to AP-1, decreased enhancer activity by approximately 70%. Conversely, coexpression of Fra-2 in combination with JunD or c-Jun and p300 increased enhancer activity 6- to 10-fold. Introduction of JunD and Fra-2 into nondecidual cells is sufficient to confer enhancer activity. JunD and Fra-2 protein expression was markedly increased in secretory phase endometrium and decidua of early pregnancy (high PRL content) compared with proliferative phase endometrium (no PRL). These investigations indicate that the 5'-flanking region of the human PRL gene contains a decidua-specific enhancer between nt -2,040/-1,505 and AP-1 binding sites within this enhancer region are critical for activity.
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PMID:Identification of a decidua-specific enhancer on the human prolactin gene with two critical activator protein 1 (AP-1) binding sites. 1126 14

We investigated whether peroxisome proliferator-activated receptor gamma (PPARgamma) ligands (ciglitazone, troglitazone, and 15-deoxy-Delta(12,14) prostaglandin J(2)) inhibited cyclooxygenase-2 (COX-2) induction in human epithelial cells. Ligands of PPARgamma inhibited phorbol ester (phorbol 12-myristate 13-acetate, PMA)-mediated induction of COX-2 and prostaglandin E(2) synthesis. Nuclear run-offs revealed increased rates of COX-2 transcription after treatment with PMA, an effect that was inhibited by PPARgamma ligands. PMA-mediated induction of COX-2 promoter activity was inhibited by PPARgamma ligands; this suppressive effect was prevented by overexpressing a dominant negative form of PPARgamma or a PPAR response element decoy oligonucleotide. The stimulatory effects of PMA were mediated by a cyclic AMP response element in the COX-2 promoter. Treatment with PMA increased activator protein-1 (AP-1) activity and the binding of c-Jun, c-Fos, and ATF-2 to the cyclic AMP response element, effects that were blocked by PPARgamma ligands. These findings raised questions about the mechanism underlying the anti-AP-1 effect of PPARgamma ligands. The induction of c-Jun by PMA was blocked by PPARgamma ligands. Overexpression of either c-Jun or CREB-binding protein/p300 partially relieved the suppressive effect of PPARgamma ligands. When CREB-binding protein and c-Jun were overexpressed together, the ability of PPARgamma ligands to suppress PMA-mediated induction of COX-2 promoter activity was essentially abrogated. Bisphenol A diglycidyl ether, a compound that binds to PPARgamma but lacks the ability to activate transcription, also inhibited PMA-mediated induction of AP-1 activity and COX-2. Taken together, these findings are likely to be important for understanding the anti-inflammatory and anti-cancer properties of PPARgamma ligands.
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PMID:Peroxisome proliferator-activated receptor gamma ligands suppress the transcriptional activation of cyclooxygenase-2. Evidence for involvement of activator protein-1 and CREB-binding protein/p300. 3190 Mar 73

The Sma and Mad related (Smad) family proteins are critical mediators of the transforming growth factor-beta (TGF-beta) superfamily signaling. After TGF-beta-mediated phosphorylation and association with Smad4, Smad2 moves to the nucleus and activates expression of specific genes through cooperative interactions with DNA-binding proteins, including members of the winged-helix family of transcription factors, forkhead activin signal transducer (FAST)-1 and FAST2. TGF-beta has also been described to activate other signaling pathways, such as the c-Jun N-terminal Kinase (JNK) pathway. Here, we show that activation of JNK cascade blocked the ability of Smad2 to mediate TGF-beta-dependent activation of the FAST proteins. This inhibitory activity is mediated through the transcriptional factor c-Jun, which enhances the association of Smad2 with the nuclear transcriptional corepressor TG-interacting factor (TGIF), thereby interfering with the assembly of Smad2 and the coactivator p300 in response to TGF-beta signaling. Interestingly, c-Jun directly binds to the nuclear transcriptional corepressor TGIF and is required for TGIF-mediated repression of Smad2 transcriptional activity. These studies thus reveal a mechanism for suppression of Smad2 signaling pathway by JNK cascade through transcriptional repression.
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PMID:c-Jun interacts with the corepressor TG-interacting factor (TGIF) to suppress Smad2 transcriptional activity. 1137 41

The adenovirus E1A protein regulates transcription of cellular genes via its interaction with the transcriptional coactivators p300/CBP. The collagenase promoter activated by the c-Jun protein is repressed by E1A. Here we show that E1A repression is specific for c-Jun, as E1A does not repress the collagenase promoter activated by the homologous transcription factor EB1. Using chimeras of c-Jun and EB1, we demonstrate that a 12 amino acid region in the basic region of the c-Jun DNA-binding domain is essential for repression by E1A. Since repression requires the binding of p300 to E1A, we studied the involvement of p300 acetyltransferase activity in the repression mechanism. We demonstrate that c-Jun is acetylated in vivo, and mutational analysis identified Lys271 in the c-Jun basic region to be essential for repression of the collagenase promoter by E1A. In addition, Lys271 is acetylated both in vitro and in vivo. These results suggest that the specific repression of the collagenase promoter by E1A involves acetylation of c-Jun.
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PMID:A specific lysine in c-Jun is required for transcriptional repression by E1A and is acetylated by p300. 1168 49

c-Jun is a member of the activator protein 1 family, and its interaction with different nuclear factors generates a wide spectrum of complexes that regulate transcription of different promoters. H ferritin promoter transcription is tightly dependent on nuclear factor Y (NFY). Ferritin transcription is activated by c-Jun, although the promoter does not contain a canonical binding site. NFY, on the other hand, does not bind c-Jun in vitro, whereas in vivo c-Jun is found in the complex containing NFY. Moreover, a c-Jun-GCN4 chimaeric construct containing only the transactivation domain of Jun and the basic-region leucine-zipper domain of GCN4 stimulates the H ferritin promoter. A synthetic GAL4 promoter and the cognate activator, the fusion protein NFY-GAL4, are potently activated by c-Jun. Titration of p300 by co-expressing E1A abolishes the stimulatory effect. Moreover, another p300-dependent promoter, the cAMP-response element, can be superactivated by c-Jun using the same mechanism. These data indicate that c-Jun, when activated or overexpressed, is recruited to the H ferritin promoter by p300, which links NFY, bound to DNA, to the complex. These results add a new level of complexity to transcriptional regulation by c-Jun, which can activate p300-dependent promoters without binding directly to the target DNA.
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PMID:An alternative model of H ferritin promoter transactivation by c-Jun. 1190 46

We present evidence that the inducer-specific regulation of the human tumor necrosis factor alpha (TNF-alpha) gene in T cells involves the assembly of distinct higher-order transcription enhancer complexes (enhanceosomes), which is dependent upon inducer-specific helical phasing relationships between transcription factor binding sites. While ATF-2, c-Jun, and the coactivator proteins CBP/p300 play a central role in TNF-alpha gene activation stimulated by virus infection or intracellular calcium flux, different sets of activators including NFATp, Sp1, and Ets/Elk are recruited to a shared set of transcription factor binding sites depending upon the particular stimulus. Thus, these studies demonstrate that the inducer-specific assembly of unique enhanceosomes is a general mechanism by which a single gene is controlled in response to different extracellular stimuli.
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PMID:Inducer-specific enhanceosome formation controls tumor necrosis factor alpha gene expression in T lymphocytes. 1190 56


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