Roles of zinc-binding domain of bacterial RNA polymerase in transcription.

Transcription is an essential and multistep process carried out by RNA polymerase (RNAP). In bacterial RNAP, in addition to the catalytic core domain, multiple other conserved domains are also identified to play regulatory roles in transcription. One such domain is the zinc-binding domain (ZBD) located at the N terminus of the largest subunit β' in bacterial RNAP, whose homolog is also reported in eukaryotic RNAPs. Recent structural and biochemical studies have revealed various key roles of the conserved β' ZBD during different steps of transcription. In this review, we summarize recent progress on the regulatory roles of this β' ZBD in bacterial transcription.