MYB Binding Protein 1A (MYBBP1A)

The protooncogene MYB is predominantly expressed in immature hemopoietic cells where it plays an important role in hemopoietic cell proliferation and differentiation. Oncogenically activated forms of MYB are generally N- and/or C-terminal truncations of the normal MYB protein. Removal of the C terminus of MYB disrupts or deletes a region termed the negative regulatory domain (NRD), resulting in an increase in DNA binding, transactivation, and transformation by MYB. One feature of the NRD is a leucine zipper-like motif. Point mutations that disrupt this motif also enhance the transactivating and transforming potential of MYB. Murine Myb-binding protein-1a (Mybbp1a), originally called P160, was identified by its ability to interact specifically with Myb via this leucine zipper-like motif .