Compensatory change of interacting amino acids in the coevolution of transcriptional coactivator MBF1 and TATA-box-binding protein.

To elucidate the transcriptional regulation in eukaryotic genome network, it is important to understand coevolution of transcription factors, transcriptional coactivators, and TATA-box-binding protein (TBP). In this study, coevolution of transcriptional coactivator multiprotein-bridging factor 1 and its interacting target TBP was first evaluated experimentally by examining if compensatory amino acid changes took place at interacting sites of both proteins. The experiments were conducted by identifying interaction sites and comparing the amino acids at these sites among different organisms. Here, we provide evidence for compensatory changes of transcription coactivator and its interacting target, presenting the 1st report that transcription coactivator may have undergone coevolution with TBP.