Regulated nucleocytoplasmic transport of protein kinase D in response to G protein-coupled receptor activation

J Biol Chem. 2001 Dec 28;276(52):49228-35. doi: 10.1074/jbc.M109395200. Epub 2001 Oct 18.

Abstract

Protein kinase D (PKD)/protein kinase C mu is a serine/threonine protein kinase activated by growth factors, antigen-receptor engagement, and G protein-coupled receptor (GPCR) agonists via a phosphorylation-dependent mechanism that requires protein kinase C (PKC) activity. In order to investigate the dynamic mechanisms associated with GPCR signaling, the intracellular distribution of PKD was analyzed in live cells by imaging fluorescent protein-tagged PKD and in fixed cells by immunocytochemistry. We found that PKD shuttled between the cytoplasm and the nucleus in both fibroblasts and epithelial cells. Cell stimulation with mitogenic GPCR agonists that activate PKD induced a transient nuclear accumulation of PKD that was prevented by inhibiting PKC activity. The nuclear import of PKD requires its cys2 domain in conjunction with a nuclear import receptor, while its nuclear export requires its pleckstrin homology domain and a competent Crm1-dependent nuclear export pathway. This study thus characterizes the regulated nuclear transport of a signaling molecule in response to mitogenic GPCR agonists and positions PKD as a serine kinase whose kinase activity and intracellular localization is coordinated by PKC.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3T3 Cells
  • Actins / genetics
  • Actins / metabolism
  • Active Transport, Cell Nucleus*
  • Animals
  • Bombesin / pharmacology
  • Cell Nucleus / metabolism*
  • Cytoplasm / metabolism
  • GTP-Binding Proteins / metabolism*
  • Green Fluorescent Proteins
  • Immunohistochemistry
  • Luminescent Proteins / metabolism
  • Mice
  • Protein Kinase C / metabolism*
  • Protein Structure, Tertiary
  • Receptors, Cell Surface / metabolism*
  • Recombinant Fusion Proteins / metabolism*
  • Red Fluorescent Protein
  • Vasopressins / pharmacology

Substances

  • Actins
  • Luminescent Proteins
  • Receptors, Cell Surface
  • Recombinant Fusion Proteins
  • Vasopressins
  • Green Fluorescent Proteins
  • protein kinase D
  • Protein Kinase C
  • GTP-Binding Proteins
  • Bombesin