Transcription Termination Factor Rho

From Proteopedia

Transcription termination factor Rho is a ring-shaped RNA-DNA helicase that induces release of transcription complexes at specific loci of bacterial genomes. Several structures of Rho in various liganded states haven been solved by X-ray crystallography by the J. M. Berger lab (Berkeley): 1a8v, 1pv4, 1pvo, 1xpr, 1xpu, 2a8v, and 2ht1.

The asymmetric unit solved as 2ht1 contains only two chains, so it represents only one third of the biological unit, which is a homo-hexamer. The scene here shows this (file Image:Rho1.pdb derived from [2ht1]] by symmetry operations).

Here is one representation showing the same Rho hexamer in a closed state and with .