Ets-1: ProductsEts-1 (E26 TransformationSpecific 1; also p54 and c-ets-1) is a 52-54 kDa member of the ETS family of proteins. It is found in multiple cell types and serves as a transcriptional regulator (generally activator) of multiple target genes, including prolactin, the transferrin receptor, and Cyclin E. By upregulating Cyclin E and CDK2 genes, it promotes cell-cycle progression. Ets-1 forms complexes with both transcriptional activators (AP-1 and GHF-1) and repressors (MafB and Daxx). Human Ets-1 is 441 amino acids (aa) in length. It contains one PNT domain (aa 51-136) that binds ERK2, and a DNAbinding ETS domain (aa 335-415). There are two SUMOylation sites, plus four utilized phosphorylation and acetylated lysine sites. At least four potential isoform variants are reported. One shows a deletion of aa 244-330 (termed isoform 1B), a second shows a deletion of aa 262-331, a third contains a deletion of aa 28-244, and a fourth possesses an 11 aa substitution for aa 262-441. Over aa 127-230, human Ets-1 shares 95% aa identity with mouse Ets-1.