Sterile alpha motif (SAM)/Pointed domain of ERG transcription factor
SAM Pointed domain of ERG subfamily of ETS transcriptional regulators is a putative protein-protein interaction domain. It may participate in formation of homodimers or heterodimers with ETS-2, Fli-1, ER81, and Pu-1. However, dimeric forms are inactive and SAM Pointed domain is not essential for dimerization, since ER81 and Pu-1 do not have it. In mouse, a regulator of this type binds the ESET histone H3-specific methyltransferase (human homolog is SETDB1), which leads to modification of the local chromatin structure through histone methylation. ERG regulators are involved in endothelial cell differentiation, bone morphogenesis and neural crest development. The Erg gene is a proto-oncogene. It is a target of chromosomal translocations resulting in fusions with other neighboring genes. Chimeric proteins were found in solid tumors such as myeloid leukemia or Ewing's sarcoma. Members of this subfamily are potential targets for cancer therapy.