Molecular structure of the avian and mammalian ets genes

The ets gene was originally identified as a second cell derived sequence transduced by the avian transforming retrovirus, E26. E26 induces erythroblastosis and myeloblastosis in chickens and transforms erythroblasts and myeloid cells in culture. From sequence analysis of the cloned provirus, the p135 transforming protein was found to be tripartite, with gag, myb and ets sequences. We have determined the nucleotide sequence of the v-ets homologous regions contained in chicken genomic clones which define nine domains. Two of these domains are not transcribed and thus do not represent functional exons. To further explore the function of the ets gene, we have begun characterization of the mammalian ets genes. Unlike the chicken gene, the mammalian ets genes are present on two chromosomes. The mammalian homologs of the 5' v-ets domain, ets-1, were mapped to chromosome 11 in man, to chromosome 9 in mouse, and to chromosome D1 in cat. The homologs of the 3' v-ets domain, ets-2, were mapped to human chromosome 21, to mouse chromosome 16, and to feline chromosome C2. The assignment of the ets-2 gene to the Down syndrome associated chromosome 21 may have interesting implications. This oncogene, ets has been connected with leukemias in chickens, and therefore might have a role in the increased frequency of leukemias in Down patients.