Visualization of dynamic trafficking of a protein kinase C betaII/green fluorescent protein conjugate reveals differences in G protein-coupled receptor activation and desensitization.

Published

Journal Article

Protein kinase C (PKC) links various extracellular signals to intracellular responses and is activated by diverse intracellular factors including diacylglycerol, Ca2+, and arachidonic acid. In this study, using a fully functional green fluorescent protein conjugated PKCbetaII (GFP-PKCbetaII), we demonstrate a novel approach to study the dynamic redistribution of PKC in live cells in response to G protein-coupled receptor activation. Agonist-induced PKC translocation was rapid, transient, and selectively mediated by the activation of Gqalpha- but not Gsalpha- or Gialpha-coupled receptors. Interestingly, although the stimuli were continuously present, only one brief peak of PKC membrane translocation was observed, consistent with rapid desensitization of the signaling pathway. Moreover, when GFP-PKCbetaII was used to examine cross-talk between two Gqalpha-coupled receptors, angiotensin II type 1A receptor (AT1AR) and endothelin A receptor (ETAR), activation of ETARs resulted in a subsequent loss of AT1AR responsiveness, whereas stimulation of AT1ARs did not cause desensitization of the ETAR signaling. The development of GFP-PKCbetaII has allowed not only the real time visualization of the dynamic PKC trafficking in live cells in response to physiological stimuli but has also provided a direct and sensitive means in the assessment of activation and desensitization of receptors implicated in the phospholipase C signaling pathway.

Full Text

Duke Authors

Cited Authors

  • Feng, X; Zhang, J; Barak, LS; Meyer, T; Caron, MG; Hannun, YA

Published Date

  • April 24, 1998

Published In

Volume / Issue

  • 273 / 17

Start / End Page

  • 10755 - 10762

PubMed ID

  • 9553141

Pubmed Central ID

  • 9553141

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.273.17.10755

Language

  • eng

Conference Location

  • United States