Linked Life Data

12062056

Source:http://linkedlifedata.com/resource/pubmed/id/12062056

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2002-6-13
pubmed:abstractText
The role of the PI 3-kinase cascade in regulation of cell growth is well established [1]. PKB (protein kinase B) is a key downstream effector of the PI 3-kinase pathway and is best known for its antiapoptotic effects [2,3] and the role it plays in initiation of S phase [4]. Here, we show that PKB activity is high in the G2/M phase of the cell cycle in epithelial cells. Inhibition of the PI 3-kinase pathway in MDCK cells induces apoptosis at the G2/M transition, prevents activation of cyclin B-associated kinase, and prohibits entry of the surviving cells into mitosis. All of these consequences of the inhibition of PI 3-kinase are relieved by expression of a constitutively active form of PKB (caPKB), indicating that PKB plays a role in regulation of the G2/M phase. Inhibition of PI 3-kinase results in activation of Chk1, whereas caPKB inhibits the ability of Chk1 to become activated in response to treatment with hydroxyurea. Preliminary data show that PKB phosphorylates the Chk1 polypeptide in vitro on serine 280. These results not only implicate PKB activity in transition through the G2/M stage of the cell cycle, but they also suggest the existence of crosstalk between the PI 3-kinase pathway and the key regulators of the DNA damage checkpoint machinery.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0960-9822
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
919-24
pubmed:dateRevised
2011-11-2
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
A role for PI 3-kinase and PKB activity in the G2/M phase of the cell cycle.
pubmed:affiliation
Cancer Research Institute, University of California-San Francisco, San Francisco, CA 94143-0128, USA. shtivelman@cc.ucsf.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't