Plays an important role in the regulation of rRNA transcription. Binds to rDNA promoter fragments. Interacts with cdc10. Belongs to the MYBBP1A family. Was originally thought to belong to the DNA polymerase type-B family based on conserved motifs (PubMed:12093911). Has later been shown to be unrelated to B class DNA polymerases (PubMed:12695662).