title: A common feature from different subunits of a homomeric AAA+ protein contacts three spatially distinct transcription elements.
abstract: Initiation of σ(54)-dependent transcription requires assistance to melt DNA at the promoter site but is impeded by numerous protein-protein and nucleo-protein interactions. To alleviate these inhibitory interactions, hexameric bacterial enhancer binding proteins (bEBP), a subset of the ATPases associated with various cellular activities (AAA+) protein family, are required to remodel the transcription complex using energy derived from ATP hydrolysis. However, neither the process of energy conversion nor the internal architecture of the closed promoter complex is well understood. Escherichia coli Phage shock protein F (PspF), a well-studied bEBP, contains a surface-exposed loop 1 (L1). L1 is key to the energy coupling process by interacting with Region I of σ(54) (σ(54)(RI)) in a nucleotide dependent manner. Our analyses uncover new levels of complexity in the engagement of a multimeric bEBP with a basal transcription complex via several L1s. The mechanistic implications for these multivalent L1 interactions are elaborated in the light of available structures for the bEBP and its target complexes.
authors: Division of Biology, Sir Alexander Fleming Building, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.
authors: Nan
authors: N
authors: Zhang
authors: Nicolas
authors: N
authors: Joly
authors: Martin
authors: M
authors: Buck
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry; D000595:Amino Acid Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D021122:Protein Subunits / Q000737:chemistry; D051877:RNA Polymerase Sigma 54 / Q000737:chemistry* / Q000378:metabolism; D015534:Trans-Activators / Q000737:chemistry* / Q000378:metabolism; D015533:Transcriptional Activation
chemical_list: D029968:Escherichia coli Proteins; D021122:Protein Subunits; C098954:PspF protein, E coli; D015534:Trans-Activators; D004247:DNA; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54; D000251:Adenosine Triphosphatases