Abi1/Hssh3bp1 pY213 links Abl kinase signaling to p85 regulatory subunit of PI-3 kinase in regulation of macropinocytosis in LNCaP cells

FEBS Lett. 2010 Aug 4;584(15):3279-86. doi: 10.1016/j.febslet.2010.06.029. Epub 2010 Jun 23.


Macropinocytosis is regulated by Abl kinase via an unknown mechanism. We previously demonstrated that Abl kinase activity is, itself, regulated by Abi1 subsequent to Abl kinase phosphorylation of Abi1 tyrosine 213 (pY213) [1]. Here we show that blocking phosphorylation of Y213 abrogated the ability of Abl to regulate macropinocytosis, implicating Abi1 pY213 as a key regulator of macropinocytosis. Results from screening the human SH2 domain library and mapping the interaction site between Abi1 and the p85 regulatory domain of PI-3 kinase, coupled with data from cells transfected with loss-of-function p85 mutants, support the hypothesis that macropinocytosis is regulated by interactions between Abi1 pY213 and the C-terminal SH2 domain of p85-thereby linking Abl kinase signaling to p85-dependent regulation of macropinocytosis.

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

  • Adaptor Proteins, Signal Transducing / metabolism*
  • Amino Acid Substitution / genetics
  • Cell Line, Tumor
  • Cyclic AMP / analogs & derivatives
  • Cyclic AMP / metabolism
  • Cytoskeletal Proteins / metabolism*
  • Humans
  • Male
  • Mutation / genetics
  • Phosphatidylinositol 3-Kinases / chemistry
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Phosphopeptides / metabolism
  • Phosphorylation / drug effects
  • Phosphotyrosine / metabolism*
  • Pinocytosis* / drug effects
  • Protein Binding / drug effects
  • Protein Kinase Inhibitors / pharmacology
  • Protein Structure, Tertiary
  • Proto-Oncogene Proteins c-abl / metabolism*
  • Signal Transduction* / drug effects


  • ABI1 protein, human
  • Adaptor Proteins, Signal Transducing
  • Cytoskeletal Proteins
  • Phosphopeptides
  • Protein Kinase Inhibitors
  • Phosphotyrosine
  • 8-aminohexylamino cAMP
  • Cyclic AMP
  • Phosphatidylinositol 3-Kinases
  • Proto-Oncogene Proteins c-abl