Based on studies in developing mouse megakaryocytes and T cells, SRC phosphorylates RUNX1 at seven tyrosine residues in the negative regulatory domain (Y254, Y258, Y260, Y376, Y379, Y380 and Y387). Endogenous human RUNX1 is tyrosine phosphorylated, and tyrosine residues in murine Runx1 that are phosphorylated by Src are conserved in human RUNX1. SRC-mediated phosphorylation interferes with binding of RUNX1 to GATA1, thus negatively regulating differentiation of hematopoietic progenitors. SRC-mediated phosphorylation promotes association of RUNX1 with the SWI/SNF complex (Huang et al. 2012).