Arabidopsis phosphatidylinositol phosphate kinase 1 binds F-actin and recruits phosphatidylinositol 4-kinase beta1 to the actin cytoskeleton

J Biol Chem. 2007 May 11;282(19):14121-31. doi: 10.1074/jbc.M611728200. Epub 2007 Mar 21.

Abstract

The actin cytoskeleton can be influenced by phospholipids and lipid-modifying enzymes. In animals the phosphatidylinositol phosphate kinases (PIPKs) are associated with the cytoskeleton through a scaffold of proteins; however, in plants such an interaction was not clear. Our approach was to determine which of the plant PIPKs interact with actin and determine whether the PIPK-actin interaction is direct. Our results indicate that AtPIPK1 interacts directly with actin and that the binding is mediated through a predicted linker region in the lipid kinase. AtPIPK1 also recruits AtPI4Kbeta1 to the cytoskeleton. Recruitment of AtPI4Kbeta1 to F-actin was dependent on the C-terminal catalytic domain of phosphatidylinositol-4-phosphate 5-kinase but did not require the presence of the N-terminal 251 amino acids, which includes 7 putative membrane occupation and recognition nexus motifs. In vivo studies confirm the interaction of plant lipid kinases with the cytoskeleton and suggest a role for actin in targeting PIPKs to the membrane.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • 1-Phosphatidylinositol 4-Kinase / genetics
  • 1-Phosphatidylinositol 4-Kinase / metabolism*
  • Actins / metabolism*
  • Arabidopsis / enzymology*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Cytoskeleton / metabolism*
  • Glutathione Transferase / genetics
  • Glutathione Transferase / metabolism
  • Immunoblotting
  • Mass Spectrometry
  • Phosphatidylinositol Phosphates
  • Phosphotransferases (Alcohol Group Acceptor) / genetics
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism

Substances

  • Actins
  • Arabidopsis Proteins
  • Phosphatidylinositol Phosphates
  • Recombinant Fusion Proteins
  • Glutathione Transferase
  • Phosphotransferases (Alcohol Group Acceptor)
  • 1-Phosphatidylinositol 4-Kinase
  • 1-phosphatidylinositol-4-phosphate 5-kinase
  • PIPK10 protein, Arabidopsis