Figure 1. Schematic representations of the organisation of the functional regions and domains of human B-Myb and p300.

Panel A shows the positions of functional domains in the transcriptional coactivator p300, as well as a partial list of proteins that bind to the CH3/E1A-binding region. Panel B illustrates the tripartite functional organisation of the B-Myb protein, which contains an N-terminal DNA binding region (DBD) formed by three highly homologous domains (R1, R2 and R3), a central transactivation domain (TAD), and towards the C-terminus a highly conserved region (CR) and negative regulatory domain (NRD).