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NusA interaction with the ? subunit of E. coli RNA polymerase is via the UP element site and releases autoinhibition.

ABSTRACT: Elongating Escherichia coli RNAP is modulated by NusA protein. The C-terminal domain (CTD) of the RNAP ? subunit (?CTD) interacts with the acidic CTD 2 (AR2) of NusA, releasing the autoinhibitory blockade of the NusA S1-KH1-KH2 motif and allowing NusA to bind nascent nut spacer RNA. We determined the solution conformation of the AR2:?CTD complex. The ?CTD residues that interface with AR2 are identical to those that recognize UP promoter elements A nusA-?AR2 mutation does not affect UP-dependent rrnH transcription initiation in vivo. Instead, the mutation inhibits Rho-dependent transcription termination at phage ?tR1, which lies adjacent to the ?nutR sequence. The Rho-dependent ?timm terminator, which is not preceded by a ?nut sequence, is fully functional. We propose that constitutive binding of NusA-?AR2 to ?nutR occludes Rho. In addition, the mutation confers a dominant defect in exiting stationary phase.

SUBMITTER: Schweimer K

PROVIDER: S-EPMC3134791 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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NusA interaction with the α subunit of E. coli RNA polymerase is via the UP element site and releases autoinhibition.

Schweimer Kristian K Prasch Stefan S Sujatha Pagadala Santhanam PS Bubunenko Mikhail M Gottesman Max E ME Rösch Paul P

Structure (London, England : 1993) 20110701 7

Elongating Escherichia coli RNAP is modulated by NusA protein. The C-terminal domain (CTD) of the RNAP α subunit (αCTD) interacts with the acidic CTD 2 (AR2) of NusA, releasing the autoinhibitory blockade of the NusA S1-KH1-KH2 motif and allowing NusA to bind nascent nut spacer RNA. We determined the solution conformation of the AR2:αCTD complex. The αCTD residues that interface with AR2 are identical to those that recognize UP promoter elements A nusA-ΔAR2 mutation does not affect UP-dependent ...[more]

PMID: 21742261

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Dataset Information

NusA interaction with the ? subunit of E. coli RNA polymerase is via the UP element site and releases autoinhibition.

Publications

NusA interaction with the α subunit of E. coli RNA polymerase is via the UP element site and releases autoinhibition.

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