3TJ1

Crystal Structure of RNA Polymerase I Transcription Initiation Factor Rrn3

Summary for 3TJ1

• Entry DOI: 10.2210/pdb3tj1/pdb
• Descriptor: RNA polymerase I-specific transcription initiation factor RRN3 (2 entities in total)
• Functional Keywords: heat repeat, transcription factor, nucleus, transcription
• Biological source: Saccharomyces cerevisiae (Baker's yeast)
• Cellular location: Nucleus : P36070
• Total number of polymer chains: 2
• Total formula weight: 149663.77

Authors

Blattner, C.,Jennebach, S.,Herzog, F.,Mayer, A.,Cheung, A.C.M.,Witte, G.,Lorenzen, K.,Hopfner, K.-P.,Heck, A.J.R.,Aebersold, R.,Cramer, P. (deposition date: 2011-08-23, release date: 2011-09-28, Last modification date: 2024-02-28)

Primary citation

Blattner, C.,Jennebach, S.,Herzog, F.,Mayer, A.,Cheung, A.C.,Witte, G.,Lorenzen, K.,Hopfner, K.P.,Heck, A.J.,Aebersold, R.,Cramer, P.
Molecular basis of Rrn3-regulated RNA polymerase I initiation and cell growth.
Genes Dev., 25:2093-2105, 2011

PubMed Abstract: Cell growth is regulated during RNA polymerase (Pol) I transcription initiation by the conserved factor Rrn3/TIF-IA in yeast/humans. Here we provide a structure-function analysis of Rrn3 based on a combination of structural biology with in vivo and in vitro functional assays. The Rrn3 crystal structure reveals a unique HEAT repeat fold and a surface serine patch. Phosphorylation of this patch represses human Pol I transcription, and a phospho-mimetic patch mutation prevents Rrn3 binding to Pol I in vitro and reduces cell growth and Pol I gene occupancy in vivo. Cross-linking indicates that Rrn3 binds Pol I between its subcomplexes, AC40/19 and A14/43, which faces the serine patch. The corresponding region of Pol II binds the Mediator head that cooperates with transcription factor (TF) IIB. Consistent with this, the Rrn3-binding factor Rrn7 is predicted to be a TFIIB homolog. This reveals the molecular basis of Rrn3-regulated Pol I initiation and cell growth, and indicates a general architecture of eukaryotic transcription initiation complexes.

PubMed: 21940764
DOI: 10.1101/gad.17363311

Experimental method

X-RAY DIFFRACTION (2.85 Å)