Crystal structure of the 14-subunit RNA polymerase I

Nature. 2013 Oct 31;502(7473):644-9. doi: 10.1038/nature12636. Epub 2013 Oct 23.

Abstract

Protein biosynthesis depends on the availability of ribosomes, which in turn relies on ribosomal RNA production. In eukaryotes, this process is carried out by RNA polymerase I (Pol I), a 14-subunit enzyme, the activity of which is a major determinant of cell growth. Here we present the crystal structure of Pol I from Saccharomyces cerevisiae at 3.0 Å resolution. The Pol I structure shows a compact core with a wide DNA-binding cleft and a tightly anchored stalk. An extended loop mimics the DNA backbone in the cleft and may be involved in regulating Pol I transcription. Subunit A12.2 extends from the A190 jaw to the active site and inserts a transcription elongation factor TFIIS-like zinc ribbon into the nucleotide triphosphate entry pore, providing insight into the role of A12.2 in RNA cleavage and Pol I insensitivity to α-amanitin. The A49-A34.5 heterodimer embraces subunit A135 through extended arms, thereby contacting and potentially regulating subunit A12.2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalytic Domain
  • Crystallography, X-Ray
  • DNA / chemistry
  • DNA / metabolism
  • Models, Molecular
  • Peptide Chain Elongation, Translational
  • Protein Binding
  • Protein Conformation
  • Protein Multimerization
  • Protein Subunits / chemistry*
  • RNA Polymerase I / chemistry*
  • RNA Polymerase II / chemistry
  • RNA Polymerase III / chemistry
  • Saccharomyces cerevisiae / enzymology*
  • Transcription, Genetic

Substances

  • Protein Subunits
  • DNA
  • RNA Polymerase II
  • RNA Polymerase I
  • RNA Polymerase III

Associated data

  • PDB/4C3H
  • PDB/4C3I
  • PDB/4C3J