The c-Fos and c-Jun oncoproteins and the p53 tumor suppressor protein are short-lived transcription factors. Several catabolic pathways contribute to their degradation in vivo. c-Fos and c-Jun are thus mostly degraded by the proteasome, but there is indirect evidence that, under certain experimental/physiological conditions, calpains participate in their destruction, at least to a limited extent. Lysosomes have also been reported to participate in the destruction of c-Fos. Along the same lines, p53 is mostly degraded following the ubiquitin/proteasome pathway and calpains also seem to participate in its degradation. Moreover, c-Fos, c-Jun and p53 turnovers are regulated upon activation of intracellular signalling cascades. All taken together, these observations underline the complexity of the mechanisms responsible for the selective destruction of proteins within cells.
Are there multiple proteolytic pathways contributing to c-Fos, c-Jun and p53 protein degradation in vivo?
Salvat, C.; Aquaviva, C.; Jariel-Encontre, I.; Ferrara, P.; Pariat, M.; Steff, A. M.; Carillo, S.; Piechaczyk, M.
Mol Biol Rep
1999-04 / vol 26 / pages 45-51
Humans; Animals; Mice; Signal Transduction; Proto-Oncogene Proteins c-fos/*metabolism; Cricetinae; Cell Cycle; Proto-Oncogene Proteins c-jun/*metabolism; Proteasome Endopeptidase Complex; Cysteine Endopeptidases/metabolism; Multienzyme Complexes/metabolism; Tumor Suppressor Protein p53/*metabolism