Structure of a bacterial RNA polymerase holoenzyme open promoter complex.
Initiation of transcription is a primary means for controlling gene expression. In bacteria, the RNA polymerase (RNAP) holoenzyme binds and unwinds promoter DNA, forming the transcription bubble of the open promoter complex (RPo). We have determined crystal structures, refined to 4.14 Å-resolution, of RPo containing Thermus aquaticus RNAP holoenzyme and promoter DNA that includes the full transcription bubble. The structures, combined with biochemical analyses, reveal key features supporting the formation and maintenance of the double-strand/single-strand DNA junction at the upstream edge of the -10 element where bubble formation initiates. The results also reveal RNAP interactions with duplex DNA just upstream of the -10 element and potential protein/DNA interactions that direct the DNA template strand into the RNAP active site. Addition of an RNA primer to yield a 4 base-pair post-translocated RNA:DNA hybrid mimics an initially transcribing complex at the point where steric clash initiates abortive initiation and σ(A) dissociation.
Laboratory for Molecular Biophysics, The Rockefeller University, New York, United States.
Brian
B
Bae
Laboratory for Molecular Biophysics, The Rockefeller University, New York, United States.
Andrey
A
Feklistov
Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, United States.
Agnieszka
A
Lass-Napiorkowska
Department of Biochemistry, University of Wisconsin-madison, Madison, United States.|Department of Bacteriology, University of Wisconsin-Madison, Madison, United States.
Robert
R
Landick
Laboratory for Molecular Biophysics, The Rockefeller University, New York, United States.
Seth A
SA
Darst
D018360:Crystallography, X-Ray; D004269:DNA, Bacterial / Q000737:chemistry* / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry* / Q000378:metabolism*; D020035:Holoenzymes / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011487:Protein Conformation; D013824:Thermus / Q000737:chemistry / Q000201:enzymology
D004269:DNA, Bacterial; D020035:Holoenzymes; D012321:DNA-Directed RNA Polymerases
E. coli; RNA polymerase; Thermus aquaticus; X-ray crystallography; biochemistry; biophysics; open promoter compex; structural biology; transcription