QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online 24 June 2008
doi: 10.1242/jcs.027698

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: jcs.027698v1 121/14/2339    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JCS Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Verbeek, D. S. Articles by Reits, E. A. Search for Related Content PubMed PubMed Citation Articles by Verbeek, D. S. Articles by Reits, E. A. Social Bookmarking                         What's this?

PKC mutations in spinocerebellar ataxia type 14 affect C1 domain accessibility and kinase activity leading to aberrant MAPK signaling

¹ Department of Cell Biology and Histology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
² Section Molecular Cytology, Swammerdam Institute for Life Sciences, Centre for Advanced Microscopy, University of Amsterdam, The Netherlands
³ Department of Biomedical Genetics, University Medical Center Utrecht, University of Utrecht, The Netherlands

^* Author for correspondence (e-mail: D.S.Verbeek{at}medgen.umcg.nl)

Accepted 22 April 2008

Spinocerebellar ataxia type 14 (SCA14) is a neurodegenerative disorder caused by mutations in the neuronal-specific protein kinase C gamma (PKC) gene. Since most mutations causing SCA14 are located in the PKC C1B regulatory subdomain, we investigated the impact of three C1B mutations on the intracellular kinetics, protein conformation and kinase activity of PKC in living cells. SCA14 mutant PKC proteins showed enhanced phorbol-ester-induced kinetics when compared with wild-type PKC. The mutations led to a decrease in intramolecular FRET of PKC, suggesting that they `open' PKC protein conformation leading to unmasking of the phorbol ester binding site in the C1 domain. Surprisingly, SCA14 mutant PKC showed reduced kinase activity as measured by phosphorylation of PKC reporter MyrPalm-CKAR, as well as downstream components of the MAPK signaling pathway. Together, these results show that SCA14 mutations located in the C1B subdomain `open' PKC protein conformation leading to increased C1 domain accessibility, but inefficient activation of downstream signaling pathways.

Key words: Spinocerebellar ataxia, Protein kinase C gamma, GFP, FLIM, FRET

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

Related articles in JCS:

PKC opens up in ataxia

JCS 2008 121: 1404. [Full Text]  

This article has been cited by other articles:

				H. Asai, M. Hirano, K. Shimada, T. Kiriyama, Y. Furiya, M. Ikeda, T. Iwamoto, T. Mori, K. Nishinaka, N. Konishi, et al. Protein kinase C{gamma}, a protein causative for dominant ataxia, negatively regulates nuclear import of recessive-ataxia-related aprataxin Hum. Mol. Genet., October 1, 2009; 18(19): 3533 - 3543. [Abstract] [Full Text] [PDF]

				M. M. Wouters, J. L. Roeder, V. S. Tharayil, J. E. Stanich, P. R. Strege, S. Lei, M. R. Bardsley, T. Ordog, S. J. Gibbons, and G. Farrugia Protein Kinase C{gamma} Mediates Regulation of Proliferation by the Serotonin 5-Hydroxytryptamine Receptor 2B J. Biol. Chem., August 7, 2009; 284(32): 21177 - 21184. [Abstract] [Full Text] [PDF]

				J. Goedhart and T. W.J Gadella Jr Fluorescence resonance energy transfer imaging of PKC signalling in living cells using genetically encoded fluorescent probes J R Soc Interface, February 6, 2009; 6(Suppl_1): S27 - S34. [Abstract] [Full Text] [PDF]