Skip to main content
Article thumbnail
Location of Repository

Regulation of Surface Localization of the Small Conductance Ca 2 �-activated Potassium Channel, Sk2, through Direct Phosphorylation by cAMP-dependent Protein Kinase *□S

By Yajun Ren, Lyndon F. Barnwell, Jon C. Alex, Farah D. Lubin, John P. Adelman, Paul J. Pfaffinger, Laura A. Schrader and Anne E. Anderson

Abstract

channels (SK channels) are widely expressed in diverse tissues; however, little is known about the molecular regulation of SK channel subunits. Direct alteration of ion channel subunits by kinases is a candidate mechanism for functional modulation of these channels. We find that activation of cyclic AMP-dependent protein kinase (PKA) with forskolin (50 �M) causes a dramatic decrease in surface localization of the SK2 channel subunit expressed in COS7 cells due to direct phosphorylation of the SK2 channel subunit. PKA phosphorylation studies using the intracellular domains of the SK2 channel subunit expressed as glutathione S-transferase fusion protein constructs showed that both the amino-terminal and carboxylterminal regions are PKA substrates in vitro. Mutational analysis identified a single PKA phosphorylation site within the amino-terminal of the SK2 subunit at serine 136. Mutagenesis and mass spectrometry studies identified four PKA phosphorylation sites: Ser 46

Year: 2009
OAI identifier: oai:CiteSeerX.psu:10.1.1.134.7854
Provided by: CiteSeerX
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://citeseerx.ist.psu.edu/v... (external link)
  • http://www.jbc.org/cgi/reprint... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.