Document Detail


Cellular commitment to reentry into the cell cycle after stalled DNA is determined by site-specific phosphorylation of Chk1 and PTEN.
MedLine Citation:
PMID:  18723495     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In this study, we show that depletion of Chk1 by small interfering RNA (siRNA) results in failure of reentry to the cell cycle after DNA replication has been stalled by exposure to hydroxyurea (HU). Casein kinase II (CKII) is degraded in these cells in a proteasome-dependent manner, resulting in decreased phosphorylation and PTEN levels. We show that phosphorylation of Chk1 at Ser(317) but not at Ser(345) is required for phosphorylation of PTEN at Thr(383) by CKII, making cell cycle reentry after HU treatment possible. Like Chk1 depletion, loss of PTEN due to siRNA is followed by inability to return to the cell cycle following HU. In Chk1-siRNA cells, reintroduction of wild-type PTEN but not PTEN T383A restores the ability of the cell to reenter the G(2)-M phase of the cell cycle after stalled DNA replication. We conclude that, in response to stalled DNA replication, Chk1 is phosphorylated at Ser(317) by ATR resulting in stabilization of CKII, which in turn leads to phosphorylation of PTEN at Thr(383).
Authors:
Sarah A Martin; Toru Ouchi
Related Documents :
525625 - Cyclic changes in ciliation, secretion and cell height of the oviductal epithelium in w...
18455135 - Prognostic value of a proliferation index including mib1 and argyrophilic nucleolar org...
8462285 - Comparative studies of synthesis, phosphorylation, dna binding and proteolytic characte...
12353465 - Population dynamics during cell proliferation and neuronogenesis in the developing muri...
8664985 - Effect of triiodothyronine administration on estrogen receptor contents in peripuberal ...
8940255 - Fms (csf-1 receptor) prolongs cell cycle and promotes retinoic acid-induced hypophospho...
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural    
Journal Detail:
Title:  Molecular cancer therapeutics     Volume:  7     ISSN:  1535-7163     ISO Abbreviation:  Mol. Cancer Ther.     Publication Date:  2008 Aug 
Date Detail:
Created Date:  2008-08-25     Completed Date:  2008-10-22     Revised Date:  2011-11-02    
Medline Journal Info:
Nlm Unique ID:  101132535     Medline TA:  Mol Cancer Ther     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2509-16     Citation Subset:  IM    
Affiliation:
Department of Oncological Sciences, Mount Sinai School of Medicine, New York University, New York, NY, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Base Sequence
Blotting, Western
Cell Cycle*
Cell Line
DNA / metabolism*
DNA Primers
DNA Replication
Flow Cytometry
Mice
Mutagenesis, Site-Directed
PTEN Phosphohydrolase / metabolism*
Phosphorylation
Protein Kinases / metabolism*
Grant Support
ID/Acronym/Agency:
CA 79892/CA/NCI NIH HHS; CA 90631/CA/NCI NIH HHS
Chemical
Reg. No./Substance:
0/DNA Primers; 9007-49-2/DNA; EC 2.7.-/Protein Kinases; EC 2.7.11.1/Checkpoint kinase 1; EC 3.1.3.48/PTEN protein, human; EC 3.1.3.67/PTEN Phosphohydrolase

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


Previous Document:  Anti-CD30 diabody-drug conjugates with potent antitumor activity.
Next Document:  Optimization of antibody binding to FcgammaRIIa enhances macrophage phagocytosis of tumor cells.