A novel member of the human ETS oncogene family, ERG, has recently been identified. A specific antibody was produced in rabbits with erg protein expressed and purified from E. coli. With the antibody, a 52 kD nuclear protein, with a halflife of 21 hours, encoded by the ERG gene was identified in human cell lines. This protein was detected in very limited types of cells; it was phosphorylated after PMA treatment, and bound specifically to PEA3 oligonucleotides. The results suggested that the erg protein is a new ETS gene family member of the specific DNA binding protein which may mediate signals transmitted from the membrane. To further characterize ets oncogene products as transcriptional activators, this project will establish an in vitro transcription system, which will allow us to study 1) how ets proteins and basic transcriptional factors interact with each other to promote RNA polymerase II, and 2) how ets protein and other transcriptional activators cooperate to organize cellular response to stimuli, such as growth factors, oncogenes, etc.
