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Query: EC:2.7.11.1 (
protein kinase
)
81,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A DNA element located at positions -295 to -289 of the c-fos promoter (FAP site) is highly homologous to a consensus 12-O-tetradecanoyl phorbol-13-acetate-responsive element (TRE) and to a cyclic AMP (cAMP)-responsive element (CRE). We found that an oligonucleotide containing the FAP element was a transcription regulator which was distinct from both the TRE and CRE. When cloned in multiple copies in front of a reporter gene in HeLa cells, the FAP oligonucleotide was a powerful constitutive activator sequence. Conversely, in the same cells, reporter plasmids containing multiple copies of the TRE of the human metallothionein gene required phorbol esters for their induction. In PC12 cells, the FAP oligonucleotide was cAMP responsive. Its activity was mediated through a
cAMP-dependent protein kinase
II and did not rely on ongoing protein synthesis for activation. Adenovirus E1a proteins activated viral promoters through
ATF
(activation transcription factor) consensus binding sequences identical to the CRE. However, E1a repressed the FAP oligonucleotide-associated transcriptional activity in HeLa cells. In PC12 cells, E1a neither transactivated nor transrepressed the basal and cAMP-stimulated FAP activity. In contrast, the CRE of the human c-fos promoter located at -60 was weakly induced by cAMP and E1a in both HeLa and PC12 cells. We suggest that the FAP oligonucleotide acts through a factor(s) distinct from those employed by the TRE and CRE and that the FAP-associated protein factor(s) may differ in HeLa and PC12 cells in expression or posttranslational regulation.
...
PMID:Functional analysis of an isolated fos promoter element with AP-1 site homology reveals cell type-specific transcriptional properties. 214 23
The human
ATF
and AP1 transcription factors bind to highly related DNA sequences. Their consensus binding sites differ by a single nucleotide, but this single change is crucial in determining factor binding specificity. We have previously identified an AP1 (yAP1) binding activity in yeast. In this report we identify a yeast
ATF
(yATF) binding activity whose specificity can be distinguished from that of yAP1 by the same crucial nucleotide that distinguishes binding of human
ATF
and AP1. The
ATF
binding site can act as an efficient upstream activating sequence in vivo, suggesting that yATF is a transcriptional activator. The yATF DNA-binding complex is phosphorylated and the binding activity of partially purified yATF can be enhanced in vitro by the addition of
protein kinase A
, indicating that the phosphorylation state of yATF may be important in determining its ability to bind DNA.
...
PMID:Mammalian cAMP-responsive element can activate transcription in yeast and binds a yeast factor(s) that resembles the mammalian transcription factor ANF. 253 34
We have studied the protein factors that promote transcription via binding to the cAMP response element (CRE) present in the adenovirus early region III (EIII) and early region IV (EIV) promoters. Three sets of CRE-binding phosphoproteins, ranging in molecular mass from 65-72, 38-43, and 31-37 kDa, were identified in vivo from HeLa cells. Western blot analysis revealed that all three sets of proteins identified were immunologically related to the transcription factor AP1. We found that binding of these proteins to the CRE could be regulated by phosphorylation in vitro. EivF, a 65-72-kDa protein was found to bind specifically to the adenovirus EIV promoter. We have also shown that the smaller molecular mass proteins of 31-37 and 38-43 kDa were able to bind to the CRE present in the adenovirus EIV promoter, as well as to two related DNA elements present in the adenovirus EIII promoter, the
ATF
and AP1 sites. Phosphorylation of these proteins with the
cAMP-dependent protein kinase
, affected their transcriptional activity and binding affinity to the three sites. Furthermore, the binding specificity of the 31-37-kDa polypeptides was mediated by
cAMP-dependent protein kinase
in vitro. Our data suggests that phosphorylation of factors that bind to the CRE may, in part, underlie the cellular response to the adenovirus-encoded Ela protein.
...
PMID:Phosphorylation of cellular proteins regulates their binding to the cAMP response element. 255
Early in adenovirus infection, the E1A (early region 1A) oncogene products trans-activate the other early viral transcription units, as well as some cellular promoters. The mechanism by which E1A elicits its activity is still unknown. In this report, I show that the adenovirus E2a and E3 promoters are cAMP inducible in rat pheochromocytoma PC12 cells and that this activation requires the presence of the
cAMP-dependent protein kinase
II. Using deletion mutants of the E2a promoter, it was found that the sequence TACGTCAT located between positions -70 and -77 is involved in both the cAMP response and the E1A trans-activation. Also, in the mutant PC12 cell line A126-2B, which lacks the
cAMP-dependent protein kinase
II, E1A is still able to activate E2a and E3 promoters. This suggests that E1A products may circumvent the lack of the kinase by activating an alternative signal transduction pathway, which could mimic the effect of agonists of adenylate cyclase. I propose that E1A is capable of modifying by phosphorylation, either directly or indirectly, the transcription factor that binds the ACGTCA motif. Such a factor, termed
ATF
(adenovirus transcription factor), has already been characterized and appears to have strong similarities to the transcriptional factor CREB (cAMP responsive element binding protein), which binds homologous sequences in cAMP responsive genes, such as somatostatin and c-fos.
...
PMID:Cyclic AMP induction of early adenovirus promoters involves sequences required for E1A trans-activation. 290 26
We describe a multipurpose eukaryotic expression vector that incorporates the following features: restriction sites for in-frame insertion of cDNAs of interest between sequences encoding the glutathione-S-transferase (GST) and an oligohistidine element, allowing expression of the corresponding fusion proteins; a phosphorylation site for
protein kinase A
for in vitro labeling of the fusion protein; a T7 promoter for in vitro transcription and subsequent translation; and signals for single-stranded DNA production in bacteria. We have used this vector to demonstrate the formation in vivo of complexes between the transcription factor ATFa, a member of the family of
ATF
/CRE binding proteins, and the c-Jun or c-Fos proteins. Such interactions could be detected in crude extracts from cells transfected with vectors expressing the GST-ATFa fusion protein, as well as the c-Jun or c-Fos proteins. Complexes containing both ATFa and either c-Jun or c-Fos were specifically retained on glutathione (GSH)-agarose beads as revealed by immunoblot analyses. We also show that the leucine zipper domain of ATFa is essential for this interaction.
...
PMID:Eukaryotic GST fusion vector for the study of protein-protein associations in vivo: application to interaction of ATFa with Jun and Fos. 770 40
The major regulators of the c-jun promoter are
ATF
-2 and c-Jun. They act as pre-bound heterodimers on two 'AP-1-like' sites, and are preferentially addressed by different types of extracellular signals. The transactivating potential of
ATF
-2 is stimulated to a higher extent than that of c-Jun by a broad group of agents causing DNA damage and other types of cellular stress, such as short-wavelength UV, or the alkylating compounds N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) or methylmethanesulphonate (MMS). In contrast, treatment with the phorbol ester TPA preferentially enhances c-Jun-dependent transactivation but does not affect
ATF
-2. Accordingly, UV and MMS but not TPA induce c-jun transcription in F9 cells, which express
ATF
-2, but not c-Jun. Stimulation of
ATF
-2-dependent transactivation by genotoxic agents requires the presence of threonines 69 and 71 located in the N-terminal transactivation domain. These sites are the target of p54 and p46 stress-activated protein kinases (SAPKs) which bind to, and phosphorylate
ATF
-2 in vitro. However, p46 and p54 kinase activity is not increased by phorbol ester, which strongly suggests that the
protein kinase
phosphorylating c-Jun in response to TPA is distinct from SAPKs and does not act on
ATF
-2. Our data demonstrate that distinct signal transduction pathways converge at c-Jun/
ATF
-2, whereby each subunit is individually addressed by a specific class of protein kinases. This allows fine tuned modulation of c-jun expression by a large spectrum of extracellular signals.
...
PMID:ATF-2 is preferentially activated by stress-activated protein kinases to mediate c-jun induction in response to genotoxic agents. 773 30
Treatment of hamster cells in culture with the DNA alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induces DNA polymerase beta (beta-pol) gene expression and cellular levels of the enzyme. Transcriptional activity of a cloned beta-pol promoter in transient expression assays is also stimulated. Among the requirements for these responses are methylation damage to genomic DNA, cellular
cAMP-dependent protein kinase
, and the
ATF
/CREB site of the cloned beta-pol promoter. In the present study, HeLa cell nuclear extract from MNNG-treated cells was much more active in an in vitro transcription assay than nuclear extract from normal cells. By using an oligonucleotide affinity column to deplete the nuclear extract of
ATF
/CREB, we showed that the difference was due to
ATF
/CREB activator. Purified
ATF
/CREB activator from MNNG-treated cells was approximately 10-fold more active than
ATF
/CREB purified from normal cells as a transcriptional activator for the depleted nuclear extract.
ATF
/CREB in the extract from normal cells is known to activate in vitro transcription by increasing the rate of promoter clearance [Narayan, S., Widen, S. G., Beard, W. A., & Wilson, S. H. (1994) J. Biol. Chem. 269, 12755-12763]. With
ATF
/CREB from MNNG-treated cells, the amount of preinitiation complex formed was much greater than with
ATF
/CREB from normal cells, and the kinetics of both the closed to open preinitiation complex isomerization and promoter clearance were altered. These results indicate that the mechanism of transcriptional activation secondary to DNA alkylation damage is recruitment of more preinitiation complex and alteration of the kinetic scheme of transcription initiation.
...
PMID:DNA damage-induced transcriptional activation of a human DNA polymerase beta chimeric promoter: recruitment of preinitiation complex in vitro by ATF/CREB. 781 26
Growth factors and cyclic AMP (cAMP) are known to activate distinct intracellular signaling pathways. Fibroblast growth factor (FGF) activates ras-dependent kinase cascades, resulting in the activation of MAP kinases, whereas cAMP activates
protein kinase A
. In this study, we report that growth factors and cAMP act synergistically to stimulate proenkephalin gene expression. Positive synergy between growth factor- and cAMP-activated signaling pathways on gene expression has not been previously reported, and we suggest that these synergistic interactions represent a useful model for analyzing interactions between these pathways. Transfection and mutational studies indicate that both FGF-dependent gene activation and cAMP-dependent gene activation require cAMP response element 2 (CRE-2), a previously characterized cAMP-dependent regulatory element. Furthermore, multiple copies of this element are sufficient to confer FGF regulation upon a minimal promoter, indicating that FGF and cAMP signaling converge upon transcription factors acting at CRE-2. Among many different
ATF
/AP-1 factors tested, two factors,
ATF
-3 and c-Jun, stimulate proenkephalin transcription in an FGF- or Ras-dependent fashion. Finally, we show that
ATF
-3 and c-Jun form heterodimeric complexes in SK-N-MC cells and that the levels of both proteins are increased in response to FGF but not cAMP. Together, these results indicate that growth factor- and cAMP-dependent signaling pathways converge at CRE-2 to synergistically stimulate gene expression and that
ATF
-3 and c-Jun regulate proenkephalin transcription in response to both growth factor- and cAMP-dependent intracellular signaling pathways.
...
PMID:Fibroblast growth factor and cyclic AMP (cAMP) synergistically activate gene expression at a cAMP response element. 793 70
IL-2 stimulates the proliferative response of various lymphoid cells. Previous studies showed an increase in intracellular levels of cAMP concomitant with an increase in phosphorylation of discrete proteins by
protein kinase A
at late G1 phase in mitogen-stimulated lymphocytes. Thus, experiments were undertaken to study nuclear proteins that bind to the cAMP-responsive enhancer (CRE) in cloned T lymphocytes stimulated with IL-2. With the use of a 32P-labeled CRE consensus sequence in a DNA binding gel mobility shift assay, we showed that IL-2 stimulation resulted in the induction of two major DNA-protein complexes at late G1/S during the cell cycle. This binding was competed in a dose-dependent manner by a nonlabeled CRE oligonucleotide but was not competed by a nonlabeled AP-1 oligonucleotide. Rapamycin, a potent immunosuppressant, which arrests IL-2-stimulated T lymphocytes at G1/S, inhibited the IL-2-induced CRE binding activities concomitantly with inhibition of DNA synthesis. By using specific Abs in a gel mobility shift assay, we identified two known CREB/
ATF
transcription factors in the IL-2-induced CRE complexes: the CRE binding factor (CREB), and ATF1. The induction of CREB binding by IL-2 was not associated with an increase in its abundance but was associated with a major increase in CREB phosphorylation that was particularly prominent at late G1/S. However, we found that G1/S progression induced by IL-2 was not associated with an increase in the intracellular levels of cAMP. These results suggest that 1) the transcription factors CREB and ATF1 and possibly other CRE binding proteins may have an important role in the modulation of specific gene expression at G1/S during cell cycle progression induced by IL-2. 2) The involvement of these CRE binding transcription factors in IL-2-stimulated cells is regulated via a mechanism that is not cAMP dependent.
...
PMID:Regulation of cAMP-responsive enhancer binding proteins during cell cycle progression in T lymphocytes stimulated by IL-2. 799 60
Phosphorylation of CREB (cyclic AMP [cAMP]- response element [CRE]-binding protein) by
cAMP-dependent protein kinase
(
PKA
) leads to the activation of many promoters containing CREs. In neurons and other cell types, CREB phosphorylation and activation of CRE-containing promoters can occur in response to elevated intracellular Ca2+. In cultured cells that normally lack this Ca2+ responsiveness, we confer Ca(2+)-mediated activation of a CRE-containing promoter by introducing an expression vector for Ca2+/calmodulin-dependent protein kinase type IV (CaMKIV). Activation could also be mediated directly by a constitutively active form of CaMKIV which is Ca2+ independent. The CaMKIV-mediated gene induction requires the activity of CREB/
ATF
family members but is independent of
PKA
activity. In contrast, transient expression of either a constitutively active or wild-type Ca2+/calmodulin-dependent protein kinase type II (CaMKII) fails to mediate the transactivation of the same CRE-containing reporter gene. Examination of the subcellular distribution of transiently expressed CaMKIV and CaMKII reveals that only CaMKIV enters the nucleus. Our results demonstrate that CaMKIV, which is expressed in neuronal, reproductive, and lymphoid tissues, may act as a mediator of Ca(2+)-dependent gene induction.
...
PMID:Calcium/calmodulin-dependent protein kinase types II and IV differentially regulate CREB-dependent gene expression. 806 43
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