The protein products of the ets-1 and ets-2 genes have been identified and characterized with polyclonal anti-peptide antibodies and with a monoclonal antibody prepared against a bacterially-expressed human ets-2 protein. The ets-1 protein is 52 kDa and found primarily in cells of lymphoid origin; the p56 ets-2 protein was found to be widely distributed and located in the nucleus. In addition, a nuclear p60 and p53 were identified as ets- 2-related proteins which share a limited homology by two- dimensional peptide mapping. The nuclear p56 was purified to homogeneity and its N-terminal 20 amino acid sequence determined. An oligonucleotide probe was made from this sequence to reprobe cDNA and genomic libraries for additional clones of ets-2-related proteins. The next part of the work is to purify the native form of the ets-2 protein in order to give insight into its function.