Mechanistic basis of differential cellular responses of phosphatidylinositol 3,4-bisphosphate- and phosphatidylinositol 3,4,5-trisphosphate-binding pleckstrin homology domains

J Biol Chem. 2007 Nov 2;282(44):32093-105. doi: 10.1074/jbc.M703517200. Epub 2007 Sep 6.

Abstract

Phosphatidylinositol 3,4-bisphosphate (PtdIns(3,4)P2) and phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3) are lipid second messengers that regulate various cellular processes by recruiting a wide range of downstream effector proteins to membranes. Several pleckstrin homology (PH) domains have been reported to interact with PtdIns(3,4)P2 and PtdIns(3,4,5)P3. To understand how these PH domains differentially respond to PtdIns(3,4)P2 and PtdIns(3,4,5)P3 signals, we quantitatively determined the PtdIns(3,4)P2 and PtdIns(3,4,5)P3 binding properties of several PH domains, including Akt, ARNO, Btk, DAPP1, Grp1, and C-terminal TAPP1 PH domains by surface plasmon resonance and monolayer penetration analyses. The measurements revealed that these PH domains have significant different phosphoinositide specificities and affinities. Btk-PH and TAPP1-PH showed genuine PtdIns(3,4,5)P3 and PtdIns(3,4)P2 specificities, respectively, whereas other PH domains exhibited less pronounced specificities. Also, the PH domains showed different degrees of membrane penetration, which greatly affected the kinetics of their membrane dissociation. Mutational studies showed that the presence of two proximal hydrophobic residues on the membrane-binding surface of the PH domain is important for membrane penetration and sustained membrane residence. When NIH 3T3 cells were stimulated with platelet-derived growth factor to generate PtdIns(3,4,5)P3, reversible translocation of Btk-PH, Grp1-PH, ARNO-PH, DAPP1-PH, and its L177A mutant to the plasma membrane was consistent with their in vitro membrane binding properties. Collectively, these studies provide new insight into how various PH domains would differentially respond to cellular PtdIns(3,4)P2 and PtdIns(3,4,5)P3 signals.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Membrane / metabolism
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Intracellular Membranes / metabolism
  • Mice
  • Models, Molecular
  • NIH 3T3 Cells
  • Phosphatidylinositol Phosphates / chemistry
  • Phosphatidylinositol Phosphates / metabolism*
  • Protein Structure, Tertiary
  • Receptors, Cytoplasmic and Nuclear / chemistry
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • Surface Plasmon Resonance

Substances

  • Phosphatidylinositol Phosphates
  • Receptors, Cytoplasmic and Nuclear
  • phosphatidylinositol 3,4,5-triphosphate
  • phosphatidylinositol 3,4-diphosphate
  • phosphatidylinositol receptors