Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1994-7-14
pubmed:abstractText
In this study, we examined the role of insulin, protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) cascade in activation of protein phosphatase-1 (PP-1) by using three complementary approaches. First, differentiated L6 cells were acutely exposed to 12-O-tetradecanoylphorbol-13-acetate (TPA, 400 nM) to activate PKC. In these cells, TPA caused 32% stimulation of PP-1 activity. The PP-1 stimulation by TPA was comparable to stimulation by insulin (t1/2 = 1 min and EC50 = 5 nM) with a maximum effect in 5 min. The effects of insulin and TPA were not additive. Insulin and TPA also stimulated MAPK (> 2-fold increase over basal, with myelin basic protein as a substrate). ML-9, a myosin light chain kinase inhibitor, blocked the effects of insulin and TPA on both MAPK and PP-1 activation. In the second approach, PKC was down-regulated by chronic treatment with TPA. In these cells subsequent effects of insulin on MAPK and PP-1 activation were blocked, without an effect on basal enzyme levels. In the third approach, two selective inhibitors of PKC, calphostin and chelerythrine chloride, were used to inhibit PKC. These inhibitors completely prevented insulin and TPA stimulation of MAPK and PP-1 and blocked insulin-induced translocation of PKC to the plasma membranes. We conclude that PKC plays an important role in insulin stimulation of PP-1 via the activation of MAPK cascade.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Alkaloids, http://linkedlifedata.com/resource/pubmed/chemical/Azepines, http://linkedlifedata.com/resource/pubmed/chemical/Benzophenanthridines, http://linkedlifedata.com/resource/pubmed/chemical/Calcium-Calmodulin-Dependent..., http://linkedlifedata.com/resource/pubmed/chemical/Insulin, http://linkedlifedata.com/resource/pubmed/chemical/Isoenzymes, http://linkedlifedata.com/resource/pubmed/chemical/ML 9, http://linkedlifedata.com/resource/pubmed/chemical/Naphthalenes, http://linkedlifedata.com/resource/pubmed/chemical/Phenanthridines, http://linkedlifedata.com/resource/pubmed/chemical/Phosphoprotein Phosphatases, http://linkedlifedata.com/resource/pubmed/chemical/Polycyclic Compounds, http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C, http://linkedlifedata.com/resource/pubmed/chemical/Protein Phosphatase 1, http://linkedlifedata.com/resource/pubmed/chemical/Tetradecanoylphorbol Acetate, http://linkedlifedata.com/resource/pubmed/chemical/calphostin complex, http://linkedlifedata.com/resource/pubmed/chemical/chelerythrine
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16662-7
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:7515882-Alkaloids, pubmed-meshheading:7515882-Animals, pubmed-meshheading:7515882-Azepines, pubmed-meshheading:7515882-Benzophenanthridines, pubmed-meshheading:7515882-Blotting, Western, pubmed-meshheading:7515882-Calcium-Calmodulin-Dependent Protein Kinases, pubmed-meshheading:7515882-Cell Line, pubmed-meshheading:7515882-Cytosol, pubmed-meshheading:7515882-Enzyme Activation, pubmed-meshheading:7515882-Homeostasis, pubmed-meshheading:7515882-Insulin, pubmed-meshheading:7515882-Isoenzymes, pubmed-meshheading:7515882-Kinetics, pubmed-meshheading:7515882-Muscles, pubmed-meshheading:7515882-Naphthalenes, pubmed-meshheading:7515882-Phenanthridines, pubmed-meshheading:7515882-Phosphoprotein Phosphatases, pubmed-meshheading:7515882-Phosphorylation, pubmed-meshheading:7515882-Polycyclic Compounds, pubmed-meshheading:7515882-Protein Kinase C, pubmed-meshheading:7515882-Protein Phosphatase 1, pubmed-meshheading:7515882-Rats, pubmed-meshheading:7515882-Tetradecanoylphorbol Acetate
pubmed:year
1994
pubmed:articleTitle
Stimulation of protein phosphatase-1 activity by phorbol esters. Evaluation of the regulatory role of protein kinase C in insulin action.
pubmed:affiliation
Diabetes Research Laboratory, Winthrop University Hospital, Mineola, New York 11501.
pubmed:publicationType
Journal Article