THE TATA BOX-BINDING PROTEIN-1 (TBP-1) OF MAIZE DISPLAYS PROMOTER-SPECIFIC DNA-BINDING AFFINITIES

Recombinant TATA box binding protein (TBP) of maize was analysed by DNA footprinting and electrophoretic mobility shift experiments to assess its affinity to TATA box containing Po/II promoter fragments of several plant genes and a Po/I gene promoter. While the proximal zein promoter P2 and the viral 35S promoter easily form in vitro complexes with TBP, the distal zein promoter P1, the Shrunken promoter and a maize rRNA gene promoter required the assistance of a yeast protein fraction with TFIIA activity. This latter capability demonstrates the potential of yeast general transcription factors as tools for studies on the formation of plant transcriptional complexes.