Linked Life Data

19343040

Source:http://linkedlifedata.com/resource/pubmed/id/19343040

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2009-8-17
pubmed:abstractText
Cellular FLICE-inhibitory protein (c-FLIP) proteins are crucial regulators of the death-inducing signaling complex (DISC) and caspase-8 activation. To date, three c-FLIP isoforms with distinct functions and regulation have been identified. Our previous studies have shown that the stability of c-FLIP proteins is subject to isoform-specific regulation, but the underlying molecular mechanisms have not been known. Here, we identify serine 193 as a novel in vivo phosphorylation site of all c-FLIP proteins and demonstrate that S193 phosphorylation selectively influences the stability of the short c-FLIP isoforms, as S193D mutation inhibits the ubiquitylation and selectively prolongs the half-lives of c-FLIP short (c-FLIP(S)) and c-FLIP Raji (c-FLIP(R)). S193 phosphorylation also decreases the ubiquitylation of c-FLIP long (c-FLIP(L)) but, surprisingly, does not affect its stability, indicating that S193 phosphorylation has a different function in c-FLIP(L). The phosphorylation of this residue is operated by the protein kinase C (PKC), as S193 phosphorylation is markedly increased by treatment with 12-O-tetradecanoylphorbol-13-acetate and decreased by inhibition of PKCalpha and PKCbeta. S193 mutations do not affect the ability of c-FLIP to bind to the DISC, although S193 phosphorylation is increased by death receptor stimulation. Instead, S193 phosphorylation affects the intracellular level of c-FLIP(S), which then determines the sensitivity to death-receptor-mediated apoptosis. These results reveal that the differential stability of c-FLIP proteins is regulated in an isoform-specific manner by PKC-mediated phosphorylation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1476-5403
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1215-26
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
PKC-mediated phosphorylation regulates c-FLIP ubiquitylation and stability.
pubmed:affiliation
Turku Centre for Biotechnology, University of Turku and Abo Akademi University, FIN-20521, Turku, Finland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't