Transcriptional activator; DNA-binding protein that specifically recognize the sequence 5'-YAAC[GT]G-3'. Plays an important role in the control of proliferation and differentiation of hematopoietic progenitor cells. Binds to HIPK1 (By similarity). Interacts with HIPK2, MAF, MYBBP1A and NLK. Comprised of 3 domains; an N-terminal DNA-binding domain, a centrally located transcriptional activation domain and a C-terminal domain involved in transcriptional repression. C-terminal truncated mutants display increased transactivation. Ubiquitinated; mediated by SIAH1 and leading to its subsequent proteasomal degradation. Phosphorylated by NLK on multiple sites, which induces proteasomal degradation. Phosphorylated by HIPK1. This phosphorylation reduces MYB transcription factor activity but not MYB protein levels (By similarity).