Summary information and primary citation
- PDB-id
-
6xav;
DSSR-derived features in text and
JSON formats
- Class
- transcription
- Method
- cryo-EM (7.7 Å)
- Summary
- Cryoem structure of e. coli rho-dependent transcription
pre-termination complex bound with nusg
- Reference
-
Hao Z, Epshtein V, Kim KH, Proshkin S, Svetlov V,
Kamarthapu V, Bharati B, Mironov A, Walz T, Nudler E
(2021): "Pre-termination
Transcription Complex: Structure and Function."
Mol.Cell, 81, 281. doi:
10.1016/j.molcel.2020.11.013.
- Abstract
- Rho is a general transcription termination factor
playing essential roles in RNA polymerase (RNAP) recycling,
gene regulation, and genomic stability in most bacteria.
Traditional models of transcription termination postulate
that hexameric Rho loads onto RNA prior to contacting RNAP
and then translocates along the transcript in pursuit of
the moving RNAP to pull RNA from it. Here, we report the
cryoelectron microscopy (cryo-EM) structures of two
termination process intermediates. Prior to interacting
with RNA, Rho forms a specific "pre-termination complex"
(PTC) with RNAP and elongation factors NusA and NusG, which
stabilize the PTC. RNA exiting RNAP interacts with NusA
before entering the central channel of Rho from the distal
C-terminal side of the ring. We map the principal
interactions in the PTC and demonstrate their critical role
in termination. Our results support a mechanism in which
the formation of a persistent PTC is a prerequisite for
termination.
