Protein kinase C activation by phorbol esters: do cysteine-rich regions and pseudosubstrate motifs play a role?

Trends Biochem Sci. 1991 May;16(5):167-9. doi: 10.1016/0968-0004(91)90064-3.


A model for the binding of two activators of protein kinase C (PKC), the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and diacylglycerol, to the enzyme is proposed. It is suggested that each activator is hydrogen-bonded to sulfhydryl groups of cysteine residues and to the carbonyl of an asparagine within the cysteine-rich regions of PKC. This might induce a conformational change that would disrupt the association of the inhibitory pseudosubstrate sequence with the active center of PKC.

Publication types

  • Review

MeSH terms

  • Amino Acid Sequence
  • Cysteine / metabolism*
  • Diglycerides / metabolism
  • Enzyme Activation
  • Hydrogen Bonding
  • Models, Chemical
  • Molecular Sequence Data
  • Protein Kinase C / metabolism*
  • Sulfhydryl Compounds / metabolism
  • Tetradecanoylphorbol Acetate / metabolism*


  • Diglycerides
  • Sulfhydryl Compounds
  • Protein Kinase C
  • Cysteine
  • Tetradecanoylphorbol Acetate