No abstract

Transcription can be regulated by controlling the provision of transcriptional factors (TFs), because TFs determine the transcription process by specifying the binding of RNA polymerase holoenzyme on promoters. Manipulations, such as replacing endogenous TFs with mutants obtained through directed evolution (or rational design), and introducing compatible heterogeneous TFs, are effective ways to regulate transcription. Designing artificial TFs with desired properties by following the principles of protein design and reconstructing ancestral TFs with the information gained from a perspective of evolution by multiple sequence alignments of the related TFs, are feasible alternative options. The engineered TFs can be used to create inducible protein expression systems that respond to a specific stimulus. Moreover, the engineered TFs could lead to a transcriptional profile different from that of the wild-type strains. Accordingly, these engineered TFs could be utilized to construct strains resistant to adverse conditions, since the emergence of resistance generally requires global transcriptional changes at the transcriptomic scale. Meanwhile, these engineered TFs can also be employed in the construction of sophisticatedly designed genetic circuits for diverse purposes. In this paper, we reviewed the advances in the above-mentioned aspects.