Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1997-6-16
pubmed:abstractText
Chronic stimulation of WB rat liver epithelial cells by angiotensin II (Ang II) resulted in the down-regulation of both type I and type III myo-inositol 1,4,5-trisphosphate receptors (IP3Rs). Stimulation with vasopressin, bradykinin, epidermal growth factor, or 12-O-tetradecanoylphorbol-13-acetate was without effect. Ang II-induced down-regulation of IP3Rs could be detected within 2 h and resulted in an inhibition of IP3-induced Ca2+ release from permeabilized cells. IP3R down-regulation was reversible, and both homo- and heterooligomers of IP3Rs were equally susceptible to Ang II-induced degradation. Chloroquine and NH4Cl increased the basal levels of IP3Rs by 2-fold, suggesting that the basal turnover of IP3Rs occurs via a lysosomal pathway. However, Ang II-induced degradation of IP3R was not affected by these inhibitors, suggesting that stimulated degradation of IP3Rs occurs via a non-lysosomal pathway. The cysteine protease and proteasomal inhibitor N-acetyl-Leu-Leu-norleucinal completely prevented Ang II-mediated down-regulation of IP3Rs, whereas the structural analog N-acetyl-Leu-Leu-methioninal was without effect. Lactacystin, a highly specific proteasome inhibitor, also blocked Ang II-mediated IP3R degradation. Stimulation with Ang II increased the amount of IP3R immunoprecipitated by anti-ubiquitin antibodies. We conclude that Ang II-stimulated IP3R degradation involves enhanced ubiquitination of the protein and degradation by the proteasome pathway.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Acetylcysteine, http://linkedlifedata.com/resource/pubmed/chemical/Angiotensin II, http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels, http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Endopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Proteinase Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Inositol 1,4,5-Trisphosphate, http://linkedlifedata.com/resource/pubmed/chemical/Inositol 1,4,5-Trisphosphate..., http://linkedlifedata.com/resource/pubmed/chemical/Multienzyme Complexes, http://linkedlifedata.com/resource/pubmed/chemical/Proteasome Endopeptidase Complex, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cytoplasmic and Nuclear, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitins, http://linkedlifedata.com/resource/pubmed/chemical/lactacystin
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12454-61
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Angiotensin II-induced down-regulation of inositol trisphosphate receptors in WB rat liver epithelial cells. Evidence for involvement of the proteasome pathway.
pubmed:affiliation
Department of Pathology, Thomas Jefferson University School of Medicine, Philadelphia, Pennsylvania 19107, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.