Search results for "c-Fos"
showing 10 items of 59 documents
Sucrose self-administration and CNS activation in the rat
2011
We have previously reported that administration of insulin into the arcuate nucleus of the hypothalamus decreases motivation for sucrose, assessed by a self-administration task, in rats. Because the pattern of central nervous system (CNS) activation in association with sucrose self-administration has not been evaluated, in the present study, we measured expression of c-Fos as an index of neuronal activation. We trained rats to bar-press for sucrose, according to a fixed-ratio (FR) or progressive-ratio (PR) schedule and mapped expression of c-Fos immunoreactivity in the CNS, compared with c-Fos expression in handled controls. We observed a unique expression of c-Fos in the medial hypothalam…
MeCP2 haplodeficiency and early-life stress interaction on anxiety-like behavior in adolescent female mice
2021
Abstract Background Early-life stress can leave persistent epigenetic marks that may modulate vulnerability to psychiatric conditions later in life, including anxiety, depression and stress-related disorders. These are complex disorders with both environmental and genetic influences contributing to their etiology. Methyl-CpG Binding Protein 2 (MeCP2) has been attributed a key role in the control of neuronal activity-dependent gene expression and is a master regulator of experience-dependent epigenetic programming. Moreover, mutations in the MECP2 gene are the primary cause of Rett syndrome and, to a lesser extent, of a range of other major neurodevelopmental disorders. Here, we aim to study…
The effect of long context exposure on cued conditioning and c-fos expression in the rat forebrain
2004
The c-fos expression was used to study the neural substrates of the cued fear conditioning acquisition, preceded by a short exposure versus a long exposure to the conditioning context. A long-context exposure (either during the night or during the day) prior to conditioning, was associated with low freezing in the learning test. Differences in the c-fos expression of CA1, CA3, BL Amygdala, LS and BNST were found between the short- or long-context groups with a pre-exposure before cued conditioning. Ce Amygdala showed no differences in the c-fos expression labeling. We reported the hippocampal c-fos activation during the cued fear conditioning acquisition. Specifically, the CA1 activation co…
Activation of gp 130 by IL-6/soluble IL-6 receptor induces neuronal differentiation
1998
Interleukin-6 (IL-6) on target cells binds to the specific IL-6 receptor (IL-6R) and subsequently induces homodimerization of the signal-transducing protein gp130. Cells which express gp130 but no IL-6R and which therefore do not respond to IL-6 can be stimulated by the complex of IL-6 and soluble IL-6R (slL-6R). Here we show that on rat pheochromocytoma cells (PC12), the combination of IL-6 and slL-6R but not IL-6 alone induces expression of c-fos, GAP-43 and neuron-specific enolase followed by neuron-specific differentiation and formation of a neuronal network. The differentiation was dose-and time-dependent and followed the same kinetics as nerve-growth factor (NGF)-induced differentiati…
Monoclonal anti-fosB antibody specific for predetermined, nonstructural region of the fosB protein.
1997
Comparison of the primary structures and theoretical prediction of the potential antigenic determinant of the deduced Fos proteins reveals the presence of a nonstructural and hydrophilic region juxtaposed to the leucine zipper and nonconserved among the Fos protein family. To develop monoclonal anti-peptide antibodies capable of distinguishing all Fos-proteins, synthetic peptides specific for the mentioned predicted region were synthesized manually by the "tea-bag" method. Immunization of Balb/c mice with fosB-related synthetic peptide BSA gave rise to mouse hybridoma cell line K21 (IgG1, kappa) secreting highly specific antibodies against corresponding human fosB protein. Fine mapping of t…
Selective uptake and degradation of c-Fos and v-Fos by rat liver lysosomes
1996
AbstractThe transcription factor c-Fos is a short-lived protein and calpains and ubiquitin-dependent systems have been proposed to be involved in its degradation. In this report, we consider a lysosomal degradation pathway for c-Fos. Using a cell-free assay, we have found that freshly isolated lysosomes can take up and degrade c-Fos with high efficiency. v-Fos, the oncogenic counterpart of c-Fos, can also be taken up by lysosomes, yet the amount of incorporated protein is much lower. c-Fos uptake is independent of its phosphorylation state but it appears to be regulated by dimerization with differentially phosphorylated forms of c-Jun, while v-Fos escapes this regulation. Moreover, we show …
The RNA binding protein tristetraprolin influences the activation state of murine dendritic cells
2010
Abstract Dendritic cells (DCs) serve to maintain peripheral tolerance under steady state conditions. Upon triggering by activation signals they initiate strong immune responses. The activation of DCs is accompanied by a rapid upregulation of proinflammatory cytokines, which were shown in other cell types to be regulated by mechanisms at the transcriptional and posttranscriptional level. Tristetraprolin (TTP), an important RNA binding protein, is involved in the regulation of mRNA stability of such cytokines. In this study we analyzed the significance of TTP for mouse DCs, which were derived from TTP −/− and WT bone marrow progenitor cells (BM-DCs). Unstimulated BM-DCs of TTP −/− mice expres…
Evaluation of the Role of Candida albicans Agglutinin-Like Sequence (Als) Proteins in Human Oral Epithelial Cell Interactions
2012
The fungus C. albicans uses adhesins to interact with human epithelial surfaces in the processes of colonization and pathogenesis. The C. albicans ALS (agglutinin-like sequence) gene family encodes eight large cell-surface glycoproteins (Als1-Als7 and Als9) that have adhesive function. This study utilized C. albicans Δals mutant strains to investigate the role of the Als family in oral epithelial cell adhesion and damage, cytokine induction and activation of a MAPK-based (MKP1/c-Fos) signaling pathway that discriminates between yeast and hyphae. Of the eight Δals mutants tested, only the Δals3 strain showed significant reductions in oral epithelial cell adhesion and damage, and cytokine pro…
Attraction to sexual pheromones and associated odorants in female mice involves activation of the reward system and basolateral amygdala
2005
Adult female mice are innately attracted to non-volatile pheromones contained in male-soiled bedding. In contrast, male-derived volatiles become attractive if associated with non-volatile attractive pheromones, which act as unconditioned stimulus in a case of Pavlovian associative learning. In this work, we study the chemoinvestigatory behaviour of female mice towards volatile and non-volatile chemicals contained in male-soiled bedding, in combination with the analysis of c-fos expression induced by such a behaviour to clarify: (i) which chemosensory systems are involved in the detection of the primary attractive non-volatile pheromone and of the secondarily attractive volatiles; (ii) where…
Distinct patterns of Fos immunoreactivity in striatum and hippocampus induced by different kinds of novelty in mice.
2010
In this study the immediate-early gene Fos was used to investigate the response to different novel stimuli in a wide array of brain regions including the hippocampus, the rhinal cortex, the frontal cortex and different components of the striatal complex. Independent groups of CD-1 mice were exposed to three different novelty conditions: (1) novel environment (empty open field); (2) complex novel environment (i.e. open field containing objects); and (3) identity-based detection of novel objects. We observed that a complex novel environment and a knowledge-based novelty modulated Fos levels in both the dorsal and the ventral components of the striatum, while Fos immunoreactivity in the medial…