2RF4

Crystal structure of the RNA Polymerase I subcomplex A14/43

Summary for 2RF4

• Entry DOI: 10.2210/pdb2rf4/pdb
• Related: 1Y14 2CKZ
• Descriptor: DNA-directed RNA polymerase I subunit RPA4 (2 entities in total)
• Functional Keywords: transferase dna/rna, dna-binding, phosphorylation, rna polymerase i, pol i, poli, rpoli, nuclear protein, nucleolar protein, transcription, transferase, ddrp, rpb4/7, ribosome biogenesis, dna-directed rna polymerase, nucleus
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Cellular location: Nucleus, nucleolus : P46669 P50106
• Total number of polymer chains: 6
• Total formula weight: 101696.92

Authors

Geiger, S.R.,Kuhn, C.D.,Cramer, P. (deposition date: 2007-09-28, release date: 2008-01-15, Last modification date: 2024-11-20)

Primary citation

Kuhn, C.D.,Geiger, S.R.,Baumli, S.,Gartmann, M.,Gerber, J.,Jennebach, S.,Mielke, T.,Tschochner, H.,Beckmann, R.,Cramer, P.
Functional architecture of RNA polymerase I.
Cell(Cambridge,Mass.), 131:1260-1272, 2007

PubMed Abstract: Synthesis of ribosomal RNA (rRNA) by RNA polymerase (Pol) I is the first step in ribosome biogenesis and a regulatory switch in eukaryotic cell growth. Here we report the 12 A cryo-electron microscopic structure for the complete 14-subunit yeast Pol I, a homology model for the core enzyme, and the crystal structure of the subcomplex A14/43. In the resulting hybrid structure of Pol I, A14/43, the clamp, and the dock domain contribute to a unique surface interacting with promoter-specific initiation factors. The Pol I-specific subunits A49 and A34.5 form a heterodimer near the enzyme funnel that acts as a built-in elongation factor and is related to the Pol II-associated factor TFIIF. In contrast to Pol II, Pol I has a strong intrinsic 3'-RNA cleavage activity, which requires the C-terminal domain of subunit A12.2 and, apparently, enables ribosomal RNA proofreading and 3'-end trimming.

PubMed: 18160037
DOI: 10.1016/j.cell.2007.10.051

Experimental method

X-RAY DIFFRACTION (3.1 Å)