Using cryo-EM to uncover mechanisms of bacterial

Transcription is the principal control point for bacterial gene expression, and it enables a global cellular response to an intracellular or environmental trigger. Transcriptional regulation is orchestrated by transcription factors, which activate or repress transcription of target genes by modulating the activity of RNA polymerase. Dissecting the nature and precise choreography of these interactions is essential for developing a molecular understanding of transcriptional regulation. While the contribution of X-ray crystallography has been invaluable, the 'resolution revolution' of cryo-electron microscopy has transformed our structural investigations, enabling large, dynamic and often transient transcription complexes to be resolved that in many cases had resisted crystallisation. In this review, we highlight the impact cryo-electron microscopy has had in gaining a deeper understanding of transcriptional regulation in bacteria. We also provide readers working within the field with an overview of the recent innovations available for cryo-electron microscopy sample preparation and image reconstruction of transcription complexes.

Automated summary

Transcription is a key control point for bacterial gene expression, with transcription factors playing a crucial role in activating or repressing target genes. The 'resolution revolution' of cryo-electron microscopy has significantly advanced structural investigations, allowing for the resolution of dynamic and transient transcription complexes. This technique has had a profound impact on gaining a deeper understanding of transcriptional regulation in bacteria.