Linked Life Data

11445557

Source:http://linkedlifedata.com/resource/pubmed/id/11445557

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
2001-8-20
pubmed:abstractText
Activation of Akt/PKB by growth factors requires multiple phosphorylation events. Phosphorylation of Thr(308) and Ser(473) of Akt by its upstream kinase(s) or autophosphorylation is critical for optimal activation of its kinase activity. Here, we present evidence that tyrosine phosphorylation is required for Akt activation. Epidermal growth factor treatment induces tyrosine phosphorylation of Akt in COS1 and PC3M cells, which is abrogated by PP2, a selective inhibitor for Src family tyrosine kinases. Elevated Akt activity is observed in v-Src transformed NIH3T3 cells, which is accompanied with increased tyrosine phosphorylation of Akt. Akt activity induced by growth factors is significantly reduced in SYF cells lacking Src, Yes, and Fyn, which can be restored by introducing c-Src, but not the kinase-inactive Src, back to these cells. Furthermore, we have identified two tyrosine residues near the activation loop of Akt that are important for its activation. Substitution of these residues with phenylalanine abolishes Akt kinase activity stimulated by growth factors. These two YF mutants fail to block Forkhead transcription factor activity in 293 cells and are unable to prevent apoptosis induced by matrix detachment. Our data suggest that, in addition to phosphorylation of Thr(308) and Ser(473), tyrosine phosphorylation of Akt may be essential for its biological function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
31858-62
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Regulation of Akt/PKB activation by tyrosine phosphorylation.
pubmed:affiliation
Department of Laboratory Medicine and Pathology and Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't