Linked Life Data

9497384

Source:http://linkedlifedata.com/resource/pubmed/id/9497384

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1998-4-7
pubmed:abstractText
Various brain K+ channels, which may normally exist as complexes of alpha (pore-forming) and beta (auxiliary) subunits, were subjected to regulation by metabotropic glutamate receptors. Kv1.1/Kvbeta1.1 is a voltage-dependent K+ channel composed of alpha and beta proteins that are widely expressed in the brain. Expression of this channel in Xenopus oocytes resulted in a current that had fast inactivating and noninactivating components. Previously we showed that basal and protein kinase A-induced phosphorylation of the alpha subunit at Ser-446 decreases the fraction of the noninactivating component. In this study we investigated the effect of protein kinase C (PKC) on the channel. We showed that a PKC-activating phorbol ester (phorbol 12-myristate 13-acetate (PMA)) increased the noninactivating fraction via activation of a PKC subtype that was inhibited by staurosporine and bisindolylmaleimide but not by calphostin C. However, it was not a PKC-induced phosphorylation but rather a dephosphorylation that mediated the effect. PMA reduced the basal phosphorylation of Ser-446 significantly in plasma membrane channels and failed to affect the inactivation of channels having an alpha subunit that was mutated at Ser-446. Also, the activation of coexpressed mGluR1a known to activate phospholipase C mimicked the effect of PMA on the inactivation via induction of dephosphorylation at Ser-446. Thus, this study identified a potential neuronal pathway initiated by activation of metabotropic glutamate receptor 1a coupled to a signaling cascade that possibly utilized PKC to induce dephosphorylation and thereby to decrease the extent of inactivation of a K+ channel.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
273
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6495-502
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:9497384-Amino Acid Sequence, pubmed-meshheading:9497384-Animals, pubmed-meshheading:9497384-Cell Membrane, pubmed-meshheading:9497384-Electric Conductivity, pubmed-meshheading:9497384-Electrophysiology, pubmed-meshheading:9497384-Ion Channel Gating, pubmed-meshheading:9497384-Kv1.1 Potassium Channel, pubmed-meshheading:9497384-Molecular Sequence Data, pubmed-meshheading:9497384-Oocytes, pubmed-meshheading:9497384-Patch-Clamp Techniques, pubmed-meshheading:9497384-Phosphorylation, pubmed-meshheading:9497384-Potassium Channels, pubmed-meshheading:9497384-Potassium Channels, Voltage-Gated, pubmed-meshheading:9497384-Protein Binding, pubmed-meshheading:9497384-Protein Kinase C, pubmed-meshheading:9497384-Receptors, Metabotropic Glutamate, pubmed-meshheading:9497384-Signal Transduction, pubmed-meshheading:9497384-Tetradecanoylphorbol Acetate, pubmed-meshheading:9497384-Xenopus laevis
pubmed:year
1998
pubmed:articleTitle
Activation of a metabotropic glutamate receptor and protein kinase C reduce the extent of inactivation of the K+ channel Kv1.1/Kvbeta1.1 via dephosphorylation of Kv1.1.
pubmed:affiliation
Department of Physiology and Pharmacology, Sackler School of Medicine, Tel-Aviv University, 69978 Ramat Aviv, Israel.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't