Linked Life Data

2162838

Source:http://linkedlifedata.com/resource/pubmed/id/2162838

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1990-8-1
pubmed:abstractText
It is now well established that autophosphorylation of a threonine residue located next to each calmodulin-binding domain in the subunits of type II Ca2+/calmodulin-dependent protein kinase causes the kinase to remain active, although at a reduced rate, after Ca2+ is removed from the reaction. This autophosphorylated form of the kinase is still sensitive to Ca2+/calmodulin, which is required for a maximum catalytic rate. After removal of Ca2+, new sites are autophosphorylated by the partially active kinase. Autophosphorylation of these sites abolishes sensitivity of the kinase to Ca2+/calmodulin (Hashimoto, Y., Schworer, C. M., Colbran, R. J., and Soderling, T. R. (1987) J. Biol. Chem. 262, 8051-8055). We have identified two pairs of homologous residues, Thr305 and Ser314 in the alpha subunit and Thr306 and Ser315 in the beta subunit, that are autophosphorylated only after removal of Ca2+ from an autophosphorylation reaction. The sites were identified by direct sequencing of labeled tryptic phosphopeptides isolated by reverse-phase high pressure liquid chromatography. Thr305-306 is rapidly dephosphorylated by purified protein phosphatases 1 and 2A, whereas Ser314-315 is resistant to dephosphorylation. We have shown by selective dephosphorylation that the presence of phosphate on Thr305-306 blocks sensitivity of the kinase to Ca2+/calmodulin. In contrast, the presence of phosphate on Ser314-315 is associated with an increase in the Kact for Ca2+/calmodulin of only about 2-fold, producing a relatively small decrease in sensitivity to Ca2+/calmodulin.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11204-12
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:2162838-Adenosine Triphosphate, pubmed-meshheading:2162838-Amino Acid Sequence, pubmed-meshheading:2162838-Animals, pubmed-meshheading:2162838-Binding Sites, pubmed-meshheading:2162838-Calcium, pubmed-meshheading:2162838-Calcium-Calmodulin-Dependent Protein Kinases, pubmed-meshheading:2162838-Calmodulin, pubmed-meshheading:2162838-Cattle, pubmed-meshheading:2162838-Chromatography, High Pressure Liquid, pubmed-meshheading:2162838-Enzyme Activation, pubmed-meshheading:2162838-Kinetics, pubmed-meshheading:2162838-Molecular Sequence Data, pubmed-meshheading:2162838-Peptide Fragments, pubmed-meshheading:2162838-Phosphorylation, pubmed-meshheading:2162838-Phosphoserine, pubmed-meshheading:2162838-Phosphothreonine, pubmed-meshheading:2162838-Protein Kinases, pubmed-meshheading:2162838-Rabbits, pubmed-meshheading:2162838-Rats, pubmed-meshheading:2162838-Threonine, pubmed-meshheading:2162838-Trypsin
pubmed:year
1990
pubmed:articleTitle
Activation of type II calcium/calmodulin-dependent protein kinase by Ca2+/calmodulin is inhibited by autophosphorylation of threonine within the calmodulin-binding domain.
pubmed:affiliation
Division of Biology, California Institute of Technology, Pasadena 91125.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't