GENOMIC STRUCTURE OF THE MAIZE TATA-BOX BINDING-PROTEIN-1 (TBP-1) - CONSERVED EXON INTRON STRUCTURE IN EUKARYOTIC TBP GENES/

The gene system of the TATA-box binding protein (TBP) is well suited f or the study of the evolutionary conservation of essential components of eukaryotic transcription initiation. In this context we have isolat ed and sequenced the maize TBP gene for a comparison with TBP genes fr om other organisms. In particular, a molecular phylogenetic analysis o f the exon/intron structure of these genes including the archaeal TBP homolog (Thermococcus celer) was performed, revealing that the intron insertion probably occurred after the early appearance of the characte ristic tandem repeat within the highly conserved C-terminal domain of all known TBPs, but before separation of the eukaryotic progenitor int o the different kingdoms.