Linked Life Data

1645716

Source:http://linkedlifedata.com/resource/pubmed/id/1645716

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
1991-7-10
pubmed:abstractText
A glycogen synthase phosphatase was purified from the yeast Saccharomyces cerevisiae. The purified yeast phosphatase displayed one major protein band which coincided with phosphatase activity on nondenaturing polyacrylamide gel electrophoresis. This phosphatase had a molecular mass of about 160,000 Da determined by gel filtration and was comprised of three subunits, termed A, B, and C. The subunit molecular weights estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were 60,000 (A), 53,000 (B), and 37,000 (C), indicating that this yeast glycogen synthase phosphatase is a heterotrimer. On ethanol treatment, the enzyme was dissociated to an active species with a molecular weight of 37,000 estimated by gel filtration. The yeast phosphatase dephosphorylated yeast glycogen synthase, rabbit muscle glycogen phosphorylase, casein, and the alpha subunit of rabbit muscle phosphorylase kinase, was not sensitive to heat-stable protein phosphatase inhibitor 2, and was inhibited 90% by 1 nM okadaic acid. Dephosphorylation of glycogen synthase, phosphorylase, and phosphorylase kinase by this yeast enzyme could be stimulated by histone H1 and polylysines. Divalent cations (Mg2+ and Ca2+) and chelators (EDTA and EGTA) had no effect on dephosphorylation of glycogen synthase or phosphorylase while Mn2+ stimulated enzyme activity by approximately 50%. The specific activity and kinetics for phosphorylase resembled those of mammalian phosphatase 2A. An antibody against a synthetic peptide corresponding to the carboxyl terminus of the catalytic subunit of rabbit skeletal muscle protein phosphatase 2A reacted with subunit C of purified yeast phosphatase on immunoblots, whereas the analogous peptide antibody against phosphatase 1 did not. These data show that this yeast glycogen synthase phosphatase has structural and catalytic similarity to protein phosphatase 2A found in mammalian tissues.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10925-32
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:1645716-Chromatography, Affinity, pubmed-meshheading:1645716-Chromatography, DEAE-Cellulose, pubmed-meshheading:1645716-Chromatography, Gel, pubmed-meshheading:1645716-Chromatography, Ion Exchange, pubmed-meshheading:1645716-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:1645716-Enzyme Activation, pubmed-meshheading:1645716-Ethers, Cyclic, pubmed-meshheading:1645716-Glycogen-Synthase-D Phosphatase, pubmed-meshheading:1645716-Immunoblotting, pubmed-meshheading:1645716-Kinetics, pubmed-meshheading:1645716-Macromolecular Substances, pubmed-meshheading:1645716-Molecular Weight, pubmed-meshheading:1645716-Okadaic Acid, pubmed-meshheading:1645716-Phosphoprotein Phosphatases, pubmed-meshheading:1645716-Protein Phosphatase 1, pubmed-meshheading:1645716-Protein Phosphatase 2, pubmed-meshheading:1645716-Saccharomyces cerevisiae, pubmed-meshheading:1645716-Substrate Specificity
pubmed:year
1991
pubmed:articleTitle
Identification of a glycogen synthase phosphatase from yeast Saccharomyces cerevisiae as protein phosphatase 2A.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Medical College of Ohio, Toledo 43699-0008.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't