Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1987-10-26
pubmed:abstractText
The activity of inositol-1,4,5-trisphosphate 3-kinase in the cytosol fraction of guinea pig macrophages was assayed with special reference to the dependence on the free Ca2+ concentration. The enzyme activity, as assessed by the production of inositol 1,3,4,5-tetrakisphosphate was reversibly activated by free Ca2+ concentrations ranging from 10(-7) to 10(-6)M. The calmodulin antagonists, W-7 and chlorpromazine, inhibited the Ca2+-activated enzyme activity in a dose-dependent fashion, thereby indicating that calmodulin may be involved in the activation by Ca2+. The content of calmodulin in the cytosol fraction (about 2.8 micrograms/mg of cytosol protein) was markedly reduced to less than 0.03 microgram/mg of proteins by subfractionation by ammonium sulfate, followed by an anion-exchange chromatography. The subfraction obtained by the chromatography showed no Ca2+ dependence in the enzyme activity, while an exogenous addition of calmodulin with 10(-6)M Ca2+ increased the enzyme activity. The enzyme activity was retained on a calmodulin-affinity column in the presence of Ca2+, and was eluted from the column by lowering the free Ca2+ concentration by adding ethylene glycol bis(beta-aminoethyl ether)-N,N'-tetraacetic acid. These results clearly indicate that calmodulin activates the inositol-1,4,5-trisphosphate 3-kinase activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:volume
257
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
363-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Activation by calmodulin of inositol-1,4,5-trisphosphate 3-kinase in guinea pig peritoneal macrophages.
pubmed:affiliation
Department of Biochemistry, Faculty of Dentistry, Kyushu University, Fukuoka, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't