Linked Life Data

15389585

Source:http://linkedlifedata.com/resource/pubmed/id/15389585

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-11-30
pubmed:abstractText
In eukaryotic cells, DNA double strand breaks (DSBs) cause the prompt phosphorylation of serine 139 at the carboxy terminus of histone H2AX to generate gamma-H2AX, detectable by Western blotting or immunofluorescence. The consensus sequence at the phosphorylation site implicates the phosphatidylinositol 3-like family of protein kinases in H2AX phosphorylation. It remains open whether ATM (ataxia telangiectasia mutated) is the major H2AX kinase, or whether other members of the family, such as DNA-PK (DNA dependent protein kinase) or ATR (ATM and Rad3 related), contribute in a functionally complementary manner. To address this question, we measured global H2AX phosphorylation in cell lysates and foci formation in individual cells of either wild type or mutant (ATM or DNA-PK) genetic background. Normal global phosphorylation kinetics is observed after irradiation in cells defective either in ATM or DNA-PK alone, suggesting a complementary contribution to H2AX phosphorylation. This is further supported by the observation that initial H2AX phosphorylation is delayed when both kinases are inhibited by wortmannin, as well as when ATM is inhibited by caffeine in DNA-PK deficient cells. However, robust residual global phosphorylation is detectable under all conditions of genetic or chemical inhibition suggesting the function of additional kinases, such as ATR. Treatment with wortmannin, caffeine, or UCN-01 produces a strong DNA-PK dependent late global hyperphosphorylation of H2AX, uncoupled from DNA DSB rejoining and compatible with an inhibition of late steps in DNA DSB processing. Evaluation of gamma-H2AX foci formation confirms the major conclusions made on the basis of global H2AX phosphorylation, but also points to differences particularly several hours after exposure to IR. The results in aggregate implicate DNA-PK, ATM and possibly other kinases in H2AX phosphorylation. The functional significance and the mechanisms of coordination in space and time of these multiple inputs require further investigation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Cell Cycle Proteins, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Activated Protein Kinase, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/H2AFX protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Histones, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Proteins, http://linkedlifedata.com/resource/pubmed/chemical/PRKDC protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Phosphotransferases, http://linkedlifedata.com/resource/pubmed/chemical/Protein Isoforms, http://linkedlifedata.com/resource/pubmed/chemical/Protein-Serine-Threonine Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Tumor Suppressor Proteins, http://linkedlifedata.com/resource/pubmed/chemical/ataxia telangiectasia mutated...
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9541
pubmed:author
pubmed:copyrightInfo
2004 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
202
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
492-502
pubmed:dateRevised
2011-11-2
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Complex H2AX phosphorylation patterns by multiple kinases including ATM and DNA-PK in human cells exposed to ionizing radiation and treated with kinase inhibitors.
pubmed:affiliation
Department of Radiation Oncology, Division of Experimental Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't