Evidence for self‐association of the alternative sigma factor σ54. (11th February 2013)

• Record Type: Journal Article
• Authors: Sabbatini, Massimo; Vezzoli, Alessandro; Milani, Mario; Bertoni, Giovanni
• Is Part Of: FEBS journal. Volume 280:Number 5(2013)
• Page Start: 1371
• Page End: 1378
• Publication Date: 2013-02-11
• Subjects: Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pathology, Molecular -- Periodicals; 572
• DOI: 10.1111/febs.12129
• Languages: English
• ISSNs: 1742-464X

Abstract

<abstract abstract-type="main" id="febs12129-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="febs12129-sec-0001" sec-type="section"> <p>Sigma factor σ<sup>54</sup> has a distinct <italic>modus operandi</italic> for mediating the activation of bacterial RNA polymerase (RNAP) at promoter recognition motifs 12 and 24 bp upstream from transcription start sites. σ<sup>54</sup> was thought to act as monomer in all transcription steps. However, we provide evidence that σ<sup>54</sup> of <italic>Pseudomonas putida</italic> interacts stably with itself. The interface between monomers involves contacts in σ<sup>54</sup> regions I and III, sequences that play key roles in the transcription activation of σ<sup>54</sup>–RNAP holoenzyme. These roles include interactions with activator proteins and the −12 and −24 motifs. In particular, we detected inter‐monomer contacts between region I, and between region I and the C–terminal portion of region III. Our results suggest a new auto‐antagonistic regulatory state of σ<sup>54</sup>.</p> </sec> <sec id="febs12129-sec-0002" sec-type="section"> <title>Structured digital abstract</title> <p> <list id="febs12129-list-0001" list-type="bullet"> <list-item> <p>σ54 and σ54 bind by molecular sieving (View Interaction: 1, 2)</p> </list-item> <list-item> <p>σ54 and σ54 bind by blue native page (View interaction)</p> </list-item> <list-item> <p>P. aeruginosa σ54 physically interacts with P. aeruginosa σ54 by two hybrid (View interaction)</p> </list-item> <list-item> <p>σ54 physically interacts with σ54 by two hybrid (View Interaction: 1, 2, 3)</p> </list-item> <list-item> <p>p53 physically interacts with SV40T by two hybrid (View interaction)</p> </list-item> </list> </p> </sec> </abstract>