To evaluate relationships between c-fos proto-oncogene expression and specific lineages of hematopoietic differentiation we analyzed the constitutive and TPA-induced expression of the c-fos gene in a wide variety of fresh human leukemic cells. High constitutive c-fos expression was detected in acute leukemias with monocytic phenotype (FAB M4/M5) and in subsets of B lymphoid leukemias, some of w...

Granule cells (GCs) of the dentate gyrus (DG) are considered to be quiescent—they rarely fire action potentials. In contrast, the other glutamatergic cell type in the DG, hilar mossy cells (MCs) often have a high level of spontaneous activity based on recordings in hippocampal slices. MCs project to GCs, so activity in MCs could play an important role in activating GCs. Therefore, we investigat...

We have investigated by Northern blot analysis the expression of c-fos protooncogene in human peripheral blood polymorphonuclear leukocytes (PMN). Freshly isolated PMN, unlike highly purified circulating lymphoid cells, showed high levels of c-fos transcripts. Appreciable c-fos mRNA was detected in monocytes, but in lesser amounts compared with PMN. Upon exposure to a series of agents that func...

The oncoprotein c-Fos is a well-recognized AP-1 transcription factor. In addition, this protein associates with the endoplasmic reticulum and activates the synthesis of phospholipids. However, the mechanism by which c-Fos stimulates the synthesis of phospholipids in general and the specific lipid pathways activated are unknown. Here we show that induction of quiescent cells to reenter growth pr...

The proto-oncogene c-fos is a major nuclear target for signal transduction pathways involved in the regulation of cell growth, differentiation, and transformation. Using the multistep skin carcinogenesis model, we have directly tested the ability of c-fos-deficient mice to develop cancer. Upon treatment with a tumor promoter, c-fos knockout mice carrying a v-H-ras transgene were able to develop...

Fos-Tau-LacZ (FTL) transgenic mice are used to visualize the anatomical connectivity of neurons that express c-Fos, an immediate early gene, in response to activation. In contrast to typical c-Fos protein expression, which is localized to the nucleus of stimulated neurons, activation of the c-Fos gene results in beta galactosidase (β-gal) expression throughout the entire cytoplasm of activated ...

Recent studies indicate that insulin and insulin-like growth factors regulate development of the nervous system. The signal transduction pathways that mediate the neurotrophic responses to these peptides are largely unknown. The aims of this study were to examine the regulation of c-fos mRNA expression by insulin and insulin-like growth factor I (IGF-I) in postmitotic neurons derived from fetal...

One of the earliest responses of cells upon exposure to DNA-damaging agents is the induction of c-fos. To elucidate the biological role of Fos expression, we analyzed cells deficient in c-Fos upon treatment with different DNA-damaging agents, including carcinogens and antineoplastic drugs. We show that cells lacking c-Fos are hypersensitive with regard to reproductive cell death, apoptosis, and...

One of the earliest responses of cells upon exposure to DNA-damaging agents is the induction of c-fos. To elucidate the biological role of Fos expression, we analyzed cells deficient in c-Fos upon treatment with different DNA-damaging agents, including carcinogens and antineoplastic drugs. We show that cells lacking c-Fos are hypersensitive with regard to reproductive cell death, apoptosis, and...

Wang, L. D., M. Wang, A. Todisco, E. Grand, and J. Del Valle. The human histamine H2 receptor regulates c-jun and c-fos in a differential manner. Am J Physiol Cell Physiol 278: C1246–C1255, 2000.—Previously, we demonstrated that activation of the human H2 receptor (hH2R) leads to an increase in c-fos transcription and cell proliferation. The purpose of these studies was to examine whether hH2R ...