RNA polymerase I structure and transcription regulation

@article{Engel2013RNAPI,
  title={RNA polymerase I structure and transcription regulation},
  author={Christoph Engel and Sarah Sainsbury and Alan C. M. Cheung and Dirk Kostrewa and Patrick Cramer},
  journal={Nature},
  year={2013},
  volume={502},
  pages={650-655}
}
Transcription of ribosomal RNA by RNA polymerase (Pol) I initiates ribosome biogenesis and regulates eukaryotic cell growth. The crystal structure of Pol I from the yeast Saccharomyces cerevisiae at 2.8 Å resolution reveals all 14 subunits of the 590-kilodalton enzyme, and shows differences to Pol II. An ‘expander’ element occupies the DNA template site and stabilizes an expanded active centre cleft with an unwound bridge helix. A ‘connector’ element invades the cleft of an adjacent polymerase… 
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TLDR
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TLDR
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TLDR
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TLDR
The results show that although general features of eukaryotic transcription initiation are conserved, Pol I and Pol II use them differently in their respective transcription initiation complexes.
Structural basis of RNA polymerase I pre-initiation complex formation and promoter melting
TLDR
The authors present the cryo-EM structure of a trapped early intermediate stage of promoter-recruited Pol I, which reveals the interactions of the basal rDNA transcription machinery with the native promoter, and discusses the mechanistic implications.
Structural basis of RNA polymerase I pre-initiation complex formation and promoter melting.
Transcription of the ribosomal RNA precursor by RNA polymerase (Pol) I is a prerequisite for the biosynthesis of ribosomes in eukaryotes. Compared to Pols II and III, the mechanisms underlying
Structural biology: Pivotal findings for a transcription machine
TLDR
The basic architecture of Pol I resembles those of Pol II and Pol III, but its DNA-binding cleft adopts a wider conformation than seen in the other RNA polymerases, and other unique features also provide insights into the functional roles of its components.
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