Linked Life Data

9334202

Source:http://linkedlifedata.com/resource/pubmed/id/9334202

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
42
pubmed:dateCreated
1997-11-17
pubmed:abstractText
Protein kinase C (PKC) is activated at the nucleus during the G2 phase of cell cycle, where it is required for mitosis. However, the mechanisms controlling cell cycle-dependent activation of nuclear PKC are not known. We now report that nuclear levels of the major physiologic PKC activator diacylglycerol (DAG) fluctuate during cell cycle. Specifically, nuclear DAG levels in G2/M phase cells are 2. 5-3-fold higher than in G1 phase cells. In synchronized cells, nuclear DAG levels rise to a peak coincident with the G2/M phase transition and return to basal levels in G1 phase cells. This increase in DAG level is sufficient to stimulate betaII PKC-mediated phosphorylation of its mitotic nuclear envelope substrate lamin B in vitro. Isolated nuclei from G2 phase cells contain an active phospholipase activity capable of generating DAG in vitro. Nuclear phospholipase activity is inhibited by the selective phosphatidylinositol-specific phospholipase C (PI-PLC) inhibitor 1-O-octadeyl-2-O-methyl-sn-glycero-3-phosphocholine and neomycin sulfate, but not by the phosphatidylcholine-PLC selective inhibitor D609 or inhibitors of phospholipase D-mediated DAG generation. Treatment of synchronized cells with 1-O-octadeyl-2-O-methyl-sn-glycero-3-phosphocholine leads to decreased nuclear PI-PLC activity and cell cycle blockade in the G2 phase, suggesting a role for nuclear PI-PLC in the G2/M phase transition. Our data are consistent with the hypothesis that nuclear PI-PLC generates DAG to activate nuclear betaII PKC, whose activity is required for mitosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26313-7
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
A role for nuclear phosphatidylinositol-specific phospholipase C in the G2/M phase transition.
pubmed:affiliation
Sealy Center for Oncology and Hematology, University of Texas Medical Branch, Galveston, Texas 77555-1048, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't