c-Myb and v-Myb Proteins 

    A linear representation of the chicken c-Myb protein sequence is shown. The three Myb repeats are shown in blue and the central acidic region is shown in red. The negative regulatory domain has been proposed to inhibit both transcriptional activation and DNA binding. P indicates a phosphorylation site. HLR indicates a heptad leucine repeat, mutation of which alters the function of the negative regulatory domain. Ex9A indicates the position of insertion of an alternatively spliced exon present in some forms of c-Myb. The portions of the c-Myb protein present in v-Myb of AMV and in Gag-Myb-Ets of E26 virus are shown at the bottom.

For review, see Lipsick and Wang, Oncogene 18:3047-55 (1999). [pdf]