Runt domain

The Runt domain is an evolutionary conserved protein domain.^[1] The AML1/RUNX1 gene is rearranged by the t(8;21) translocation in acute myeloid leukemia.^[2] The gene is highly similar to the Drosophila melanogaster segmentation gene runt and to the mouse transcription factor PEBP2 alpha subunit gene.^[2] The region of shared similarity, known as the Runt domain, is responsible for DNA-binding and protein-protein interaction.

In addition to the highly conserved Runt domain, the AML-1 gene product carries a putative ATP-binding site (GRSGRGKS), and has a C-terminal region rich in proline and serine residues. The protein, commonly referred to as RUNX1 (also known as acute myeloid leukemia 1 protein, AML-1, or the core-binding factor alpha-B subunit) binds to the core site, 5'-pygpyggt-3', of a number of enhancers and promoters.

The functional protein forms a heterodimer composed of an alpha and a beta subunit. The alpha subunit can bind DNA on its own and plays an essential role in the development of normal hematopoiesis (blood cell formation). CBF is a nuclear protein expressed in numerous tissue types, except brain and heart; highest levels have been found to occur in thymus, bone marrow and peripheral blood.

This domain occurs towards the N-terminus of the proteins in this entry.