Linked Life Data

1596288

Source:http://linkedlifedata.com/resource/pubmed/id/1596288

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1992-6-26
pubmed:abstractText
The bryostatins represent a unique class of activators of protein kinase C (PKC) which induce only a subset of the responses typical of the phorbol esters and block those responses to the phorbol esters which they themselves do not induce. To better understand the interaction of the bryostatins with PKC, we have synthesized [26-3H]bryostatin 4 and characterized its binding to PKC. [3H]Bryostatin 4 and [3H]phorbol 12,13-dibutyrate ([3H]PDBu) differed markedly in their binding to PKC reconstituted with phosphatidylserine (PS). The binding affinity of [3H]bryostatin 4 under these conditions was too high to measure and the rate of release of bound bryostatin was much slower than that of the phorbol esters, with a half-time of several hours. These properties caused bryostatin 1 to appear to inhibit [3H]PDBu binding under these conditions in a non-competitive fashion. Both the high potency and the slow rate of release of the bryostatins may contribute to their unique pattern of biological activity. By reconstituting PKC in a mixture of 1.5% Triton X-100:0.3% PS, we were able to establish reversible conditions for [3H]bryostatin 4 binding. Under these latter conditions, binding of [3H]bryostatin 4 was competitively inhibited by PDBu, consistent with both the bryostatin and phorbol esters binding to PKC in a qualitatively similar fashion. Binding affinities to PKC isozymes alpha, beta, and gamma were compared and little difference was found, suggesting that differential recognition by these isozymes does not account for the unique biological activity of the bryostatins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2952
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2007-14
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Binding of [3H]bryostatin 4 to protein kinase C.
pubmed:affiliation
Molecular Mechanisms of Tumor Promotion Section, National Cancer Institute, Bethesda, MD 20892.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't