B-myb proto-oncogene products interact in vivo with each other via the carboxy-terminal conserved region

Using the yeast two-hybrid assay and in vivo binding assay, we investigated whether B-myb oncogene products (B-myb) can associate with each other. Spe cificity tests of the yeast two-hybrid system showed a self-association of B-myb proteins in yeast, Cotransfection experiments demonstrated that B-myb proteins form a complex in vivo. Deletion analysis revealed that this bind ing was sufficiently mediated by the carboxy-terminal conserved region of B -myb, In addition, the B-myb self-association is directly dependent on the amount of expressed B-myb b in cells and slightly increased by the dephosph orylation state. These results suggested that B-myb could form a complex an d influence its transcriptional activity. (C) 1999 Federation of European B iochemical Societies.