Association of protein kinase Cμ with type II phosphatidylinositol 4- kinase and type I phosphatidylinositol-4-phosphate 5-kinase Academic Article uri icon

Overview

MeSH Major

  • Diagnostic Techniques and Procedures
  • Laboratories
  • Magnetics

abstract

  • Protein kinase Cmu (PKCmu), also named protein kinase D, is an unusual member of the PKC family that has a putative transmembrane domain and pleckstrin homology domain. This enzyme has a substrate specificity distinct from other PKC isoforms (Nishikawa, K., Toker, A., Johannes, F. J., Songyang, Z., and Cantley, L. C. (1997) J. Biol. Chem. 272, 952-960), and its mechanism of regulation is not yet clear. Here we show that PKCmu forms a complex in vivo with a phosphatidylinositol 4-kinase and a phosphatidylinositol-4-phosphate 5-kinase. A region of PKCmu between the amino-terminal transmembrane domain and the pleckstrin homology domain is shown to be involved in the association with the lipid kinases. Interestingly, a kinase-dead point mutant of PKCmu failed to associate with either lipid kinase activity, indicating that autophosphorylation may be required to expose the lipid kinase interaction domain. Furthermore, the subcellular distribution of the PKCmu-associated lipid kinases to the particulate fraction depends on the presence of the amino-terminal region of PKCmu including the predicted transmembrane region. These results suggest a novel model in which the non-catalytic region of PKCmu acts as a scaffold for assembly of enzymes involved in phosphoinositide synthesis at specific membrane locations.

publication date

  • September 4, 1998

Research

keywords

  • Academic Article

Identity

Digital Object Identifier (DOI)

  • 10.1074/jbc.273.36.23126

Additional Document Info

start page

  • 23126

end page

  • 33

volume

  • 273

number

  • 36