Linked Life Data

19901967

Source:http://linkedlifedata.com/resource/pubmed/id/19901967

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2010-2-4
pubmed:abstractText
Translationally controlled tumour protein (TCTP) is a highly conserved protein present in all eukaryotic organisms. Various cellular functions and molecular interactions have been ascribed to this protein, many related to its growth-promoting and antiapoptotic properties. TCTP levels are highly regulated in response to various cellular stimuli and stresses. We have shown recently that the double-stranded RNA-dependent protein kinase, PKR, is involved in translational regulation of TCTP. Here we extend these studies by demonstrating that TCTP is downregulated in response to various proapoptotic treatments, in particular agents that induce Ca(++) stress, in a PKR-dependent manner. This regulation requires phosphorylation of protein synthesis factor eIF2alpha. Since TCTP has been characterized as an antiapoptotic and Ca(++)-binding protein, we asked whether it is involved in protecting cells from Ca(++)-stress-induced apoptosis. Overexpression of TCTP partially protects cells against thapsigargin-induced apoptosis, as measured using caspase-3 activation assays, a nuclear fragmentation assay, using fluorescence-activated cell sorting analysis, and time-lapse video microscopy. TCTP also protects cells against the proapoptotic effects of tunicamycin and etoposide, but not against those of arsenite. Our results imply that cellular TCTP levels influence sensitivity to apoptosis and that PKR may exert its proapoptotic effects at least in part through downregulation of TCTP via eIF2alpha phosphorylation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1476-5594
pubmed:author
pubmed:issnType
Electronic
pubmed:day
4
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
763-73
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Roles of the translationally controlled tumour protein (TCTP) and the double-stranded RNA-dependent protein kinase, PKR, in cellular stress responses.
pubmed:affiliation
Division of Basic Medical Sciences, St George's, University of London, London, UK. ubommer@uow.edu.au
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't