6533b857fe1ef96bd12b4545
RESEARCH PRODUCT
Selective uptake and degradation of c-Fos and v-Fos by rat liver lysosomes
Enrique RocheFernando AnientoErwin KnechtAthanasios G. Papavassiliousubject
LeupeptinsProto-Oncogene Proteins c-junBiophysicsProtein degradationProtein degradationTransfectionBiochemistryc-FosCell Linechemistry.chemical_compoundStructural BiologyLysosomeGeneticsmedicineAnimalsHumansProtease InhibitorsTrypsinPhosphorylationMolecular BiologyTranscription factorc-FosCell-Free Systembiologyc-junLeupeptinc-Junv-FosCalpainCell BiologyLysosomeRecombinant ProteinsRatsKineticsOncogene Proteins v-fosmedicine.anatomical_structureLiverchemistryBiochemistrybiology.proteinPhosphorylationElectrophoresis Polyacrylamide GelLysosomesProto-Oncogene Proteins c-fosHeLa Cellsdescription
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 that c-Fos is immunologically detected in lysosomes isolated from the liver of rats treated with the protease inhibitor leupeptin. Altogether, these results suggest that lysosomes can also participate in the selective degradation of c-Fos in rat liver.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1996-07-15 | FEBS Letters |