SNAP output for PDB entry 6xh8 [SNAP web server]

PDB-id

6xh8; SNAP-derived features in text and JSON formats; DNAproDB

Class

transcription-DNA-RNA

Method

cryo-EM (4.1 Å)

Summary

Cuer-transcription activation complex with RNA transcript

Reference

Shi W, Zhang B, Jiang Y, Liu C, Zhou W, Chen M, Yang Y, Hu Y, Liu B (2021): "Structural basis of copper-efflux-regulator-dependent transcription activation." Iscience, 24, 102449. doi: 10.1016/j.isci.2021.102449.

Abstract

The copper efflux regulator (CueR), a representative member of mercury resistance regulator (MerR) family metalloregulators, controls expression of copper homeostasis-regulating genes in bacteria. The mechanism of transcription activation by CueR and other MerR family regulators is bending the spacer domain of promoter DNA. Here, we report the cryo-EM structures of the intact CueR-dependent transcription activation complexes. The structures show that CueR dimer bends the 19-bp promoter spacer to realign the -35 and -10 elements for recognition by σ₇₀-RNA polymerase holoenzyme and reveal a previously unreported interaction between the DNA-binding domain (DBD) from one CueR subunit and the σ₇₀ nonconserved region (σNCR). Functional studies have shown that the CueR-σNCR interaction plays an auxiliary role in CueR-dependent transcription, assisting the activation mechanism of bending promoter DNA by CueR dimer. Because DBDs are highly conserved in sequence and structure, this transcription-activating mechanism could be generally used by MerR family regulators.