Molecular analysis of the ets genes and their products

Organisms from human to Drosophila have been found to contain cellular sequences and transcripts that are homologous to the ets region of the avian retrovirus, E26. Ets-related sequences are present on at least two distinct functional loci in chickens and mammals, and have been designated ets-1 and ets-2. The E26 virus transduced sequences from the chicken ets-1 locus, which encompasses over 60 kb of DNA. The ets genes characterized so far from sea urchin and Drosophila are most closely related to the 3' end of the known ets genes. The predicted viral and avian ets proteins are very similar, except at the termini. The similarity between the predicted ets proteins so far described is discussed. The ets proteins have been identified and localized by immunoprecipitation and immunofluorescence. While the ets-1 proteins are found in the nuclear and cytoplasmic fractions, the viral gag-myb-ets protein (p135) and the ets-2 proteins are nuclear. The ets-1 and ets-2 genes are differentially regulated in different cell types, probably reflecting unique controlling elements. Because chromosomal translocations have been associated with different human leukemias, studies addressing the possible association with the ETS1 (11q23) or ETS2 (21q22.3) loci are reviewed.