The pleckstrin homology domain of phospholipase C-delta 1 binds with high affinity to phosphatidylinositol 4,5-bisphosphate in bilayer membranes

Biochemistry. 1995 Dec 12;34(49):16228-34. doi: 10.1021/bi00049a039.


The pleckstrin homology (PH) domain of phospholipase C-delta 1 (PLC-delta 1) binds to phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) in phospholipid membranes with an affinity (Ka approximately 10(6) M-1) and specificity comparable to those of the native enzyme. PLC-delta 1 and its PH domain also bind inositol 1,4,5-trisphosphate, the polar head group of PI(4,5)P2, with comparable affinity and approximately 1:1 stoichiometry. A peptide corresponding to amino acids 30-43 of the PLC-delta 1 PH domain contains several basic residues predicted to bind PI(4,5)P2, but binds weakly and with little specificity for PI(4,5)P2; hence the tertiary structure of the isolated PH domain is required for high affinity PI(4,5)P2 binding. Our PI-(4,5)P2 binding results support the hypothesis that the intact PH domain, serving as a specific tether, directs PLC-delta 1 to membranes enriched in PI(4,5)P2 and permits the active site, located elsewhere in the protein, to hydrolyze multiple substrate molecules before this enzyme dissociates from the membrane surface.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Blood Proteins / chemistry*
  • Cloning, Molecular
  • Escherichia coli
  • Humans
  • Hydrogen-Ion Concentration
  • Isoenzymes / chemistry*
  • Isoenzymes / metabolism*
  • Kinetics
  • Lipid Bilayers
  • Molecular Sequence Data
  • Phospholipids / metabolism
  • Phosphoproteins*
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism*
  • Protein Structure, Tertiary
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Structure-Activity Relationship
  • Type C Phospholipases / chemistry*
  • Type C Phospholipases / metabolism*


  • Blood Proteins
  • Isoenzymes
  • Lipid Bilayers
  • Phospholipids
  • Phosphoproteins
  • Recombinant Proteins
  • platelet protein P47
  • Phosphotransferases (Alcohol Group Acceptor)
  • phosphatidylinositol 4,5-biphosphate kinase
  • Type C Phospholipases