The V5 domain of protein kinase C plays a critical role in determining the isoform-specific localization, translocation, and biological function of protein kinase C-delta and -epsilon

Research output: Contribution to journalArticle

Abstract

The catalytic domain of overexpressed protein kinase C (PKC)-delta mediates phorbol 12-myristate 13-acetate (PMA)-induced differentiation or apoptosis in appropriate model cell lines. To define the portions of the catalytic domain that are critical for these isozyme-specific functions, we constructed reciprocal chimeras, PKC-delta/epsilonV5 and -epsilon/deltaV5, by swapping the V5 domains of PKC-delta and -epsilon. PKC-delta/epsilonV5 failed to mediate PMA-induced differentiation of 32D cells, showing the essential nature of the V5 domain for PKC-delta's functionality. The other chimera, PKC-epsilon/deltaV5, endowed inactive PKC-epsilon with nearly all PKC-delta's apoptotic ability, confirming the importance of PKC-delta in this function. Green fluorescent protein (GFP)-tagged PKC-deltaV5 and -epsilon/deltaV5 in A7r5 cells showed substantial basal nuclear localization, while GFP-tagged PKC-epsilon and -delta/epsilonV5 showed significantly less, indicating that the V5 region of PKC-delta contains determinants critical to its nuclear distribution. PKC-epsilon/deltaV5-GFP showed much slower kinetics of translocation to membranes in response to PMA than parental PKC-epsilon, implicating the PKC-epsilonV5 domain in membrane targeting. Thus, the V5 domain is critical in several of the isozyme-specific functions of PKC-delta and -epsilon.

Details

Authors
  • QMJ Wang
  • GW Lu
  • WA Schlapkohl
  • A Goerke
  • Christer Larsson
  • H Mischak
  • PM Blumberg
  • JF Mushinski
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Cancer and Oncology
Original languageEnglish
Pages (from-to)129-140
JournalMolecular Cancer Research
Volume2
Issue number2
StatePublished - 2004
Peer-reviewedYes

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Tumour Cell Biology (013017530)