Pre-termination Transcription Complex: Structure and Function.
Mol Cell
; 81(2): 281-292.e8, 2021 01 21.
Article
em En
| MEDLINE
| ID: mdl-33296676
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.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fatores de Transcrição
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RNA Polimerases Dirigidas por DNA
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Regulação Bacteriana da Expressão Gênica
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Fatores de Alongamento de Peptídeos
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Proteínas de Escherichia coli
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Fatores de Elongação da Transcrição
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Escherichia coli
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Terminação da Transcrição Genética
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article