We investigated (a) if activation of the mitogen activated protein kinase (MAPK) pathway was linked to the stress activated protein kinase (SAPK) pathway and (b) if JNK was required for activation of c-Jun in Schwann cells of rat sciatic nerve following injury. To this aim, ERK1/2 and the transcription factors c-Jun and ATF-3 were studied by immunohistochemistry in segments of transected nerves...

Cooperation between STAT3 and c-Jun results in suppression of Fas Receptor (FasR) transcription, which is often seen in advanced human tumors. To identify requirements for STAT3-Jun cooperation, we elucidated the role of protein kinases that affect both transcription factors. The phosphatidylinositol 3-kinase (PI3K)-AKT signaling pathway was found capable of down-regulating both STAT3- and c-Ju...

The protooncogenes c-fos and c-jun encode nuclear proteins (fos and jun, respectively) that function cooperatively as a heterodimeric protein complex in the regulation of gene transcription. These proteins dimerize via a structural motif known as the leucine zipper and bind to activator protein-1 sites via a conserved domain that is rich in basic amino acids. Previously, we demonstrated that wh...

Fos and Jun proteins homo- or heterodimerize to form functional AP-1 transcription factors. Drosophila mutants lacking either Jun or Fos display indistinguishable dorsal open phenotypes, indicating an essential function of both Jun and Fos for embryonic dorsal closure. Here we present experiments to determine the basis for this dual requirement. By combining mutant alleles and transgenes expres...

Jun is a major component of the heterodimeric transcription factor AP-1 and is essential for embryonic development, as foetuses that lack Jun die at mid-gestation. Ubiquitous mosaic inactivation of a conditional Jun allele by cre/LoxP-mediated recombination was used to screen for novel functions of Jun and revealed that its absence results in severe malformations of the axial skeleton. More-spe...

Objective(s): To investigate the effects of Nonylphenol (NP) in pups from dams exposed during gestational and lactational periods on immediate early genes (c-jun, c-fos) in hippocampus and the learning and memory of F1 rats. Materials and Methods: Twenty eight pregnant dams, stratified by pregnancy date, were randomly assigned into 4 groups, which were gavaged with NP at the doses of 50 mg/kg/d...

Activity of the c-jun N-terminal kinase (JNK) has been shown in hematopoietic cells transformed by p210 BCR-ABL. However, analysis has not been reported for hematopoietic cells on the consequences of this activity for c-jun promoter regulation within its distinctive proximal 8-base consensus CRE-like element, an element linked to JNK-mediated increase in c-jun transcription. In the present stud...

The c-jun protooncogene encodes a nuclear protein, cJun, which is a major component of the AP-1 transcription factor. AP-1 regulates various aspects of cell proliferation and differentiation. As an immediate early response gene, the expression of the c-jun gene is affected by various extracellular stimuli, such as serum, phorbol esters, and glucocorticoids. In mouse L929 fibroblasts, dexamethas...