Myristoylated [formula omitted]-oncogene products are potently detected by the monoclonal antibody to the NH 2-terminal myristoyl-Gly-Ser-Ser-Lys [formula omitted]-peptide

Abstract

Monoclonal antibodies were raised against a synthetic NH 2-terminal myristoyl tetrapeptide ( N -myristoyl-Gly-Ser-Ser-Lys) which is characteristic of an NH 2-terminal portion of pp60 src , the transforming protein of src -oncogene. The antibody reacted with the albumin conjugated with both the N -myristoyl and N -lauroyl-tetrapeptides, but concentrations at which 50% of the immunoreaction was inhibited were 5 pmol for the N -myristoyl and 830 pmol for N -lauroyl tetrapeptidyl albumin. On the other hand, N -palmitoyl tetrapeptidyl and underivatized albumin, and Gly-Ser-Ser-Lys-Ser-Lys-Pro-Lys octapeptide had no effects. These results suggest a high affinity of the antibody for an N -myristoyl-Gly-Ser-Ser-Lys moiety. src -Oncogene products in Rous sarcoma virus-transformed cells and human colon carcinoma tumor cells were selectively identified as myristoylated pp60 src by immunoprecipitation analyses with the antibody.