The expression of the c-fos protooncogene was investigated by in situ hybridization in normal murine bone marrow cells. A strong signal was found in murine marrow cells having the morphologic features of erythroblasts. This result was confirmed in human marrow cells using a double labeling technique (in situ hybridization and immunocytochemistry). A majority (70%) of the cells expressing c-fos ...

The aim of the present study was to investigate the prognostic significance of the expression of transcription factors, c-Fos, c-Jun and transmembrane protein CD147, in urothelial carcinoma of the bladder (UCB). The current study investigated the clinical significance of these factors in the development, progression and survival analysis of UCB. Immunohistochemistry was employed to analyze c‑Fo...

Expression of B lymphocyte-induced maturation protein 1 (Blimp-1) transcription factor is essential for promoting B cell differentiation into plasma cells. However, a critical transcription factor for Blimp-1 expression in activated B cells is unclear. When splenic B cells were stimulated with CD40 ligand (CD40L) and IL-4, terminal differentiation was induced in the B cells from c-fos transgeni...

We have generated transgenic mice expressing the proto-oncogene c-fos from an H-2Kb class I MHC promoter as a tool to identify and isolate cell populations which are sensitive to altered levels of Fos protein. All homozygous H2-c-fosLTR mice develop osteosarcomas with a short latency period. This phenotype is specific for c-fos as transgenic mice expressing the fos- and jun-related genes, fosB ...

Structure-function analysis as well as studies with knock-out and transgenic mice have assigned distinct functions to c-Fos and Fra-1, two components of the transcription factor AP-1 (activator protein-1). To test whether Fra-1 could substitute for c-Fos, we generated knock-in mice that express Fra-1 in place of c-Fos. Fra-1 rescues c-Fos-dependent functions such as bone development and light-i...

Intense activation of neurons triggers the appearance of immediate expression genes, including c-Fos. This gene is related to various signal cascades involved in biochemical processes such as neuronal plasticity, cell growth and mitosis. Here we investigate the expression pattern and the refractory period of c-Fos in rats and monkey's brains after stimulation with pentylenetetrazol. Rats and mo...

The addition of exogenous barium ions to PC12 rat pheochromocytoma cells elicits a transient induction of the c-fos gene. Induction is antagonized by extracellular calcium and the dihydropyridine calcium channel blockers, and it is attenuated in the presence of calmodulin inhibitors. Thus, barium appears to enter the cell through a voltage-dependent calcium channel and, either directly or indir...

The products of the proto-oncogenes c-fos and c-jun form a tight protein complex that is a major component of the transcription factor AP1. To analyze the role of fos in the binding of this complex to the AP1 DNA recognition sequence and the mechanism of interaction in further detail, we have expressed a fos protein in E. coli using an expression vector containing the temperature-inducible lamb...

The cytochrome P450 (CYP) 2J2 arachidonic acid epoxygenase gene was down-regulated at a pre-translational level in human hepatoma-derived HepG2 cells incubated in a hypoxic environment; under these conditions, the expression of c-Jun and c-Fos mRNA and protein was increased. The 5'-upstream region of the CYP2J2 gene was isolated by amplification of a 2341 bp fragment and putative regulatory ele...

The protooncogene c-fos has been implicated in the control of proliferation and transformation of fibroblasts, and its protein product is an essential component of transcription factor AP1. The important target genes and, hence, the molecular mechanism of Fos function are, however, still unknown, partly due to the lack of a tightly regulated Fos-induction system. Here we show that different act...