CBF binds to the core site, 5'-PYGPYGGT-3', of a number of enhancers and promoters, including murine leukemia virus, polyomavirus enhancer, T-cell receptor enhancers, LCK, IL-3 and GM-CSF promoters. The alpha subunit binds DNA and appears to have a role in the development of normal hematopoiesis. Isoform AML-1L interferes with the transactivation activity of RUNX1. Acts synergistically with ELF4 to transactivate the IL-3 promoter and with ELF2 to transactivate the BLK promoter. Inhibits KAT6B-dependent transcriptional activation. Controls the anergy and suppressive function of regulatory T-cells (Treg) by associating with FOXP3. Activates the expression of IL2 and IFNG and down-regulates the expression of TNFRSF18, IL2RA and CTLA4, in conventional T-cells (By similarity). Positively regulates the expression of RORC in T-helper 17 cells (By similarity). Heterodimer with CBFB. RUNX1 binds DNA as a monomer and through the Runt domain. DNA-binding is increased by heterodimerization. Interacts with TLE1 and ALYREF/THOC4. Interacts with ELF1, ELF2 and SPI1. Interacts via its Runt domain with the ELF4 N-terminal region. Interaction with ELF2 isoform 2 (NERF-1a) may act to repress RUNX1-mediated transactivation. Interacts with KAT6A and KAT6B. Interacts with SUV39H1, leading to abrogation of transactivating and DNA-binding properties of RUNX1. Interacts with YAP1 and HIPK2. Interaction with CDK6 prevents myeloid differentiation, reducing its transcription transactivation activity. Found in a complex with PRMT5, RUNX1 and CBFB. Interacts with FOXP3. Interacts with TBX21. Interacts with DPF2 (By similarity). Expressed in skeletal muscle. Expression increases following denervation. A proline/serine/threonine rich region at the C-terminus is necessary for transcriptional activation of target genes. Phosphorylated in its C-terminus upon IL-6 treatment. Phosphorylation enhances interaction with KAT6A (By similarity). Methylated. Phosphorylated in Ser-249 Thr-272 and Ser-275 by HIPK2 when associated with CBFB and DNA. This phosphorylation promotes subsequent EP300 phosphorylation (By similarity).