Actinomycin D, C2 and VII, Inhibitors of GRB2-SHC Interaction Produced by Streptomyces.

Abstract Actinomycin D, C 2 and VII, cyclic peptides, inhibited Grb2 SH2 domain association (IC 50 5–7 μM) with a phosphotyrosine containing peptide derived from the Shc protein (pTyr317). Actinomycins are the first examples of nonphosphorylated natural ligands of SH2 domain.