Document Detail


The 19 S proteasomal subunit POH1 contributes to the regulation of c-Jun ubiquitination, stability, and subcellular localization.
MedLine Citation:
PMID:  16569633     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The AP1 (activator protein 1) transcription factor, c-Jun, is an important regulator of cell proliferation, differentiation, survival, and death. Its activity is regulated both at the level of transcription and post-translationally through phosphorylation, sumoylation, and targeted degradation. The degradation of c-Jun by the ubiquitin proteasome pathway has been well established. Here, we report that POH1, a subunit of the 19 S proteasome lid with a recently described deubiquitinase activity, is a regulator of c-Jun. Ectopic expression of POH1 in HEK293 cells decreased the level of c-Jun ubiquitination, leading to significant accumulation of the protein and a corresponding increase in AP1-mediated gene expression. The stabilization also correlated with a redistribution of c-Jun in the nucleus. These effects were reduced by mutation of a cysteine residue in the Mpr1 pad1 N-terminal plus motif of POH1 (Cys-120) and appeared to be selective for c-Jun, because POH1 had no effect on other proteasomal substrates. Our results identify a novel mechanism of c-Jun regulation in mammalian cells.
Authors:
Joseph F Nabhan; Paula Ribeiro
Related Documents :
14673133 - Assessment of the role of activator protein-1 on transcription of the mouse steroidogen...
11355693 - Possible roles of jnk pathway in the regulation of hippocampal proenkephalin and immedi...
15974953 - Hepcidin in iron metabolism.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2006-03-28
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  281     ISSN:  0021-9258     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  2006 Jun 
Date Detail:
Created Date:  2006-06-05     Completed Date:  2006-08-23     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  16099-107     Citation Subset:  IM    
Affiliation:
Institute of Parasitology, Macdonald Campus, McGill University, Ste. Anne de Bellevue, Quebec H9X 3V9, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Base Sequence
Cell Line
DNA Primers
Genes, Reporter
Humans
Immunoprecipitation
Proteasome Endopeptidase Complex / metabolism*
Proto-Oncogene Proteins c-jun / metabolism*
Reverse Transcriptase Polymerase Chain Reaction
Subcellular Fractions / metabolism*
Trans-Activators / metabolism*
Ubiquitin / metabolism*
Chemical
Reg. No./Substance:
0/DNA Primers; 0/PSMD14 protein, human; 0/Proto-Oncogene Proteins c-jun; 0/Trans-Activators; 0/Ubiquitin; EC 3.4.25.1/Proteasome Endopeptidase Complex

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Formation of F-ring isoprostane-like compounds (F3-isoprostanes) in vivo from eicosapentaenoic acid.
Next Document:  Profiling of eicosanoid production in the rat hippocampus during kainic acid-induced seizure: dual p...