Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1986-9-17
pubmed:abstractText
The participation of calcium-activated, phospholipid-dependent protein kinase in the phosphorylation of endogenous islet proteins following the exposure of cultured, neonatal pancreatic islets to stimulatory glucose concentrations was investigated by two techniques. In the first technique, islets were prelabeled with 32Pi. The major endogenous substrates for glucose-induced phosphorylation had apparent molecular masses of 130,100 +/- 1010, 100,000 +/- 700, 80,400 +/- 890, 58,100 +/- 1200, 39,800 +/- 700, and 29,400 +/- 700 Da. In the presence of 12-O-tetradecanoylphorbol 13-acetate (2 microM), an activator of calcium-activated phospholipid-dependent kinase, there was enhanced phosphorylation of proteins of 80,000, 40,000, and 29,000 Da. In the second technique, exogenous phosphorylation by [gamma-32P]ATP of proteins in a postnuclear particulate fraction was studied in the presence and absence of cofactors for Ca2+-activated, phospholipid-dependent protein kinase (Ca2+, phosphatidylserine, and unsaturated diolein). These studies were performed in islets preexposed to low (1.7 mM) or high (16.7 mM) glucose concentration prior to preparation of the postnuclear particulate fraction. Following exposure of islets to low glucose concentration, three substrates (apparent molecular masses 40,500 +/- 600, 57,100 +/- 700, and 79,400 +/- 600 Da) in the postnuclear particulate fraction exhibited enhanced phosphorylation in the presence of calcium ions, phosphatidylserine, and unsaturated diolein. In preparations of islets preexposed to 16.7 mM glucose, the phosphorylation of the protein of molecular mass about 40,000 Da was significantly reduced, indicating prior phosphorylation of the acceptor sites on this substrate in response to glucose exposure. It is concluded that stimulation of neonatal cultured islets by glucose induces the acute changes in calcium ion, phospholipid, and diacylglycerol concentration required to activate the calcium-activated phospholipid-dependent protein kinase and that the islet postnuclear particulate fraction contains at least one specific substrate for this kinase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
248
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
562-9
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Glucose-induced phospholipid-dependent protein phosphorylation in neonatal rat islets.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't