Linked Life Data

16301825

Source:http://linkedlifedata.com/resource/pubmed/id/16301825

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4-6
pubmed:dateCreated
2005-11-22
pubmed:abstractText
The KCNQ gene family comprises voltage-gated potassium channels expressed in epithelial tissues (KCNQ1, KCNQ5), inner ear structures (KCNQ1, KCNQ4) and the brain (KCNQ2-5). KCNQ4 is expressed in inner and outer hair cells of the inner ear where it determines electrical excitability. Accordingly, loss of function mutations of the KCNQ4 gene cause hearing loss. Several K+ channels including the closely related KCNQ1/KCNE1 channel are regulated by the serum- and glucocorticoid-inducible kinase (SGK) family. The present study utilized the Xenopus oocyte system to explore effects of SGK isoforms on KCNQ4 mediated K(+)-currents: KCNQ4 channels activated in a voltage dependent manner with half maximal activation at -10 mV. The peak channel activity was significantly increased by prepulsing. Coexpression of wild type SGK1 but not coexpression of the inactive mutant (K127N)SGK1 significantly increased current amplitudes (by 67 %) and significantly increased the resting potential of KCNQ4 expressing oocytes. Here we describe for the first time a prepulse dependence of KCNQ4 channels with increased currents after hyperpolarizing prepulses. Coexpression of SGK1 significantly attenuated the effect of prepulsing on peak currents. Mutation of Ser to Asp or Ala in the putative phosphorylation consensus sequence in KCNQ4 significantly decreased the sensitivity to SGK1-coexpression. In conclusion, SGK1 regulates current amplitudes and kinetic properties of KCNQ4 channel activity, an effect sensitive to mutations in the SGK1 consensus sequence of the channel.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1015-8987
pubmed:author
pubmed:copyrightInfo
(c) 2005 S. Karger AG, Basel
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
255-62
pubmed:dateRevised
2011-11-2
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Regulation of KCNQ4 potassium channel prepulse dependence and current amplitude by SGK1 in Xenopus oocytes.
pubmed:affiliation
Department of Physiology, University of Tuebingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't