Authors
Groisman, IrinaIvshina, Maria
Marin, Veronica
Kennedy, Norman J.
Davis, Roger J.
Richter, Joel D.
Student Authors
Maria IvshinaUMass Chan Affiliations
Program in Molecular MedicineDocument Type
Journal ArticlePublication Date
2006-10-04Keywords
Animals; Blotting, Western; Cell Aging; Cell Cycle; Cell Cycle Proteins; Cells, Cultured; Cyclin-Dependent Kinase Inhibitor p16; Fibroblasts; Male; Mice; Mice, Knockout; Phosphorylation; Protein Binding; Protein Biosynthesis; Proto-Oncogene Proteins c-myc; RNA, Messenger; RNA-Binding Proteins; Tumor Suppressor Protein p14ARF; Tumor Suppressor Protein p53; mRNA Cleavage and Polyadenylation FactorsBiochemistry, Biophysics, and Structural Biology
Cell and Developmental Biology
Life Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Cytoplasmic polyadenylation element-binding protein (CPEB) is a sequence-specific RNA-binding protein that promotes polyadenylation-induced translation. While a CPEB knockout (KO) mouse is sterile but overtly normal, embryo fibroblasts derived from this mouse (MEFs) do not enter senescence in culture as do wild-type MEFs, but instead are immortal. Exogenous CPEB restores senescence in the KO MEFs and also induces precocious senescence in wild-type MEFs. CPEB cannot stimulate senescence in MEFs lacking the tumor suppressors p53, p19ARF, or p16(INK4A); however, the mRNAs encoding these proteins are unlikely targets of CPEB since their expression is the same in wild-type and KO MEFs. Conversely, Ras cannot induce senescence in MEFs lacking CPEB, suggesting that it may lie upstream of CPEB. One target of CPEB regulation is myc mRNA, whose unregulated translation in the KO MEFs may cause them to bypass senescence. Thus, CPEB appears to act as a translational repressor protein to control myc translation and resulting cellular senescence.Source
Genes Dev. 2006 Oct 1;20(19):2701-12. Link to article on publisher's siteDOI
10.1101/gad.1438906Permanent Link to this Item
http://hdl.handle.net/20.500.14038/33757PubMed ID
17015432Related Resources
Link to article in PubMedae974a485f413a2113503eed53cd6c53
10.1101/gad.1438906
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