The C-Terminus of the B Cell Activator Oct-2 Functions as an Activation Domain in Yeast

Oct-1 and Oct-2 are human transcriptional activators that bind to the same DNA element but activate distinct sets of genes. We expressed these factors in S.cerevisiae and observed greater than 5-fold stimulation of a lacZ reporter gene only with Oct-2. Transfer of the Oct-2 C-terminal domain onto either Oct-1 (Oct1.2) or a nonactivating DNA-binding domain from GAL4 created activators capable of greater than 15 and 10-fold stimulation of activity, respectively. Thus, the C-terminus of Oct-2 is sufficient to confer activation potential to nonactive DNA-binding fragments in yeast.