The phalloidin binding site of F-actin

EMBO J. 1985 Nov;4(11):2815-8. doi: 10.1002/j.1460-2075.1985.tb04008.x.

Abstract

Tritium-containing affinity-labelling derivatives of phalloidin, an alkylating iodoacetyl compound (EAL) and a photolabile, carbene generating diazirine (PAL), have been reacted with rabbit muscle actin, the former after protection of thiol groups with N-ethylmaleimide. Labelled peptides generated by tryptic and/or thermolysin digestion were isolated by paper peptide mapping and characterized by determination of their amino acid sequences. EAL binds to methionine-119 and methionine-355; PAL binds to glutamic acid-117. These residues are located in regions with extremely conserved amino acid sequences. The cleft between the two domains of the actin monomer is suggested as the possible binding site for phalloidin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / isolation & purification
  • Actins / metabolism*
  • Affinity Labels
  • Amino Acid Sequence
  • Amino Acids / analysis
  • Animals
  • Binding Sites
  • Muscles / metabolism
  • Oligopeptides / metabolism*
  • Peptide Fragments / analysis
  • Phalloidine / metabolism*
  • Protein Binding
  • Rabbits
  • Trypsin

Substances

  • Actins
  • Affinity Labels
  • Amino Acids
  • Oligopeptides
  • Peptide Fragments
  • Phalloidine
  • Trypsin