Experience-dependent decrease in synaptically localized Fra-1.
Brain Res Mol Brain Res
; 78(1-2): 120-30, 2000 May 31.
Article
em En
| MEDLINE
| ID: mdl-10891591
ABSTRACT
The Fos family of transcription factors has been repeatedly shown to participate in the long-term neural responses associated with a variety of physiological stimuli, including activity-dependent plastic processes. Quite recently, several transcription factors have been found in synaptic regions, localized in dendrites and presynaptic terminals. Here we show that the transcription factor Fos-related antigen-1 (Fra-1) was detected in synaptosomes (Syn) and synaptic plasma membrane (SPM) fractions from the rat cerebral cortex and hippocampus as a single band migrating with M(r) 42-43 kDa. The 55-kDa c-Fos protein was also detected in syn and SPM fractions. Conversely, the inducible 62-65-kDa c-Fos is present in nuclear fractions from metrazole-treated animals (positive control), but not in Syn or SPM fractions. Furthermore, no Fra-2, Fos B or c-Jun immunoreactivities were detected in these same synaptic regions. DNA-mobility shift assays showed the presence of specific AP-1 binding activity in synaptic protein extracts. Immunoelectronmicroscopic analysis of cortical and hippocampal tissues revealed that Fra-1 and Fos-like immunoreactivities are localized in association with presynaptic plasma membranes. One trial inhibitory avoidance training, a hippocampal-dependent task, is associated with a time-dependent decrease (-31%) in Fra-1, but not in 55-kDa c-Fos, levels in hippocampal SPM fractions. In hippocampal homogenates, we do not detect significant changes in Fra-1 immunoreactivity, suggesting that this behavioural experience is probably accompanied by a subcellular redistribution of Fra-1 protein. These results suggest that Fra-1 may participate in the communication between synapse and the nucleus and in experience-dependent hippocampal plasticity.
Buscar no Google
Base de dados:
MEDLINE
Assunto principal:
Aprendizagem da Esquiva
/
Sinapses
/
Comportamento Animal
/
Córtex Cerebral
/
Proteínas Proto-Oncogênicas c-fos
/
Hipocampo
Limite:
Animals
Idioma:
En
Revista:
Brain Res Mol Brain Res
Assunto da revista:
BIOLOGIA MOLECULAR
/
CEREBRO
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
Argentina