Linked Life Data

2375770

Source:http://linkedlifedata.com/resource/pubmed/id/2375770

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-8-30
pubmed:abstractText
The microbial alkaloid staurosporine is a member of a recently described family of protein kinase inhibitors. [N,N-dimethyl-3H]N-dimethylstaurosporine ([3H]DMS) was prepared from staurosporine by methylation with [3H]methyl iodide. Since staurosporine inhibits protein kinase C (PKC) most potently, the binding of [3H]DMS to this enzyme was examined. Unlike [20-3H(N)]phorbol-12,13-dibutyrate ([3H]PDBu) binding to PKC, [3H]DMS binding was not calcium or phosphatidylserine (PS) dependent. Binding was reversible, with a T1/2 of 69 min and a Koff of 0.01/min. Non-specific binding was defined by a 500-fold molar excess of staurosporine and was less than 10% of total [3H]DMS binding. Specific binding of [3H]DMS was consistent with a single class of binding sites with a Kd of 3.8 +/- 0.6 nM and a Bmax of 675 +/- 30 pmol/g tissue. In competition experiments, staurosporine inhibited [3H]DMS binding with a Ki of 4.7 +/- 0.6 nM, indicating that the two alkaloids had a similar potency for PKC. Also, unlabeled DMS and staurosporine inhibited [3H]DMS binding and PKC catalysis with equivalent potencies. Highly purified rat brain PKC bound equimolar amounts of [3H]PDBu and [3H]DMS. In contrast, crude rat brain PKC, which had been proteolysed to generate a PS and Ca2+ independent enzyme (PK-M) retained the ability to bind [3H]DMS, but not [3H]PDBu. In addition, the kinase inhibitors K-252a and H-7 [1-(5-isoquinolinesulfonyl)-2-methylpiperazine] inhibited [3H]DMS binding, whereas PDBu did not. These results indicate that [3H]DMS is a useful ligand to identify catalytic inhibitors of kinase activity and to explore their mechanisms of action.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2952
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
343-50
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Characterization of specific [3H]dimethylstaurosporine binding to protein kinase C.
pubmed:affiliation
Medical Products Department, E. I. du Pont de Nemours & Co., Inc., Wilmington, DE 19898.
pubmed:publicationType
Journal Article