Linked Life Data

10574948

Source:http://linkedlifedata.com/resource/pubmed/id/10574948

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
2000-2-3
pubmed:abstractText
The progression of cells from G(2) into mitosis is blocked by exposure to DNA-damaging agents such as ionizing radiation. This G(2) delay is associated with reduced cyclin B1-specific associated histone H1 kinase activity, increased inhibitory phosphorylation of p34(Cdc2), and depressed cyclin B1 levels in HeLa cells. Induction of cyclin B1 or expression of Cdc2AF, a mutant p34(Cdc2) that lacks the sites of inhibitory phosphorylation, only partially reverses the radiation-associated G(2) delay, although both maneuvers rapidly result in increased histone H1 kinase activity. To account for the persistent G(2) delay in the face of active p34(Cdc2) kinase, we determined the location of the kinase activity. Although p34(Cdc2) was active in the cytoplasm, the nuclear p34(Cdc2) was inactive. Irradiation led to nuclear accumulation of the inactive tyrosine-phosphorylated form of p34(Cdc2), whereas the active form was seen in the cytoplasm. At later times when cells had resumed cell cycle progression, nuclear kinase activity was detectable. These results give evidence of segregation of cytoplasmic and nuclear kinase activity after DNA damage that has the effect of enhancing checkpoint control. Shielding the nucleus from the potentially deleterious effects of kinase activity after DNA damage may help irradiated human cancer cells respond to irradiation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
34779-84
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
p34(Cdc2) kinase activity is excluded from the nucleus during the radiation-induced G(2) arrest in HeLa cells.
pubmed:affiliation
Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.