The Translation Product of the Presumptive Thermococcus celer TATA-binding Protein Sequence Is a Transcription Factor Related in Structure and Function to Methanococcus Transcription Factor B

A gene for a putative homolog of TATA-binding protein (TBP) from Thermococcus celer has been expressed in Escherichia coli, and the function of the purified recombinant protein was studied in a Methanococcus-derived cell-free transcription system. Thermococcus TBP can replace archaeal transcription factor B (aTFB) in cell-free transcription reactions. This transcriptional activation is TATA box-dependent and occurs both on tRNA(Val) and protein-encoding genes as templates indicating that Thermococcus TBP is a general transcription factor. Antibodies raised against Thermococcus TBP bind to Methanococcus aTFB and inhibit a TFB activity. These findings demonstrate that Thermococcus TBP (like eucaryal TBPs) can direct specific transcription from TATA boxes.