Characterization of the DNA binding and transcriptional activation domains of the erg protein

erg, an ets related gene encodes a sequence specific DNA binding transcriptional activator protein. We have identified four functional domains of erg protein that are responsible for DNA binding, transcriptional activation and negative regulation of transcriptional activation. Deletion analysis revealed that the 3'-ets domain of the erg protein is sufficient for DNA binding activity. Analysis of these deletion mutants also revealed the presence of two autonomous transcriptional activation domains, one at the amino and the other at the carboxyterminal region. This aminoterminal transcriptional activator domain (5'-ets domain) is conserved in six of the ets genes suggesting that it (ETA, ets Transcriptional Activation domain) may contribute to a common function among these genes. The transcriptional activation function of the carboxy terminal transcriptional activation domain (CTA) was inhibited by the presence of a Negative Regulatory Transcriptional activation domain (NRT), which is located at the amino terminal region of erg DNA binding domain. These results may help in understanding the structure/function relationship of other erg/ets related proteins.