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Crosslinking mass spectrometry of yeast Pol I pre-initiation complex

ABSTRACT: In eukaryotic cells, ribosomal RNA is transcribed by RNA polymerase I (Pol I). To initiate transcription, Pol I requires the assembly of a multi-subunit pre-initiation complex (PIC). In yeast, the minimal PIC includes Pol I, the transcription factor Rrn3 and Core Factor (CF) composed of subunits Rrn6, Rrn7 and Rrn11. We have determined the cryo-EM structure of a 18-subunit yeast Pol I complex together with CF, Rrn3 and transcription scaffold. To aid in modeling the structure based on the cryo-EM map, we performed crosslinking mass spectrometry.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Katarzyna Buczak

LAB HEAD: Christoph Müller

PROVIDER: PXD006510 | Pride | 2017-07-31

REPOSITORIES: Pride

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Structural insights into transcription initiation by yeast RNA polymerase I.

Sadian Yashar Y Tafur Lucas L Kosinski Jan J Jakobi Arjen J AJ Wetzel Rene R Buczak Katarzyna K Hagen Wim Jh WJ Beck Martin M Sachse Carsten C Müller Christoph W CW

The EMBO journal 20170724 18

In eukaryotic cells, RNA polymerase I (Pol I) synthesizes precursor ribosomal RNA (pre-rRNA) that is subsequently processed into mature rRNA. To initiate transcription, Pol I requires the assembly of a multi-subunit pre-initiation complex (PIC) at the ribosomal RNA promoter. In yeast, the minimal PIC includes Pol I, the transcription factor Rrn3, and Core Factor (CF) composed of subunits Rrn6, Rrn7, and Rrn11. Here, we present the cryo-EM structure of the 18-subunit yeast Pol I PIC bound to a tr ...[more]

PMID: 28739580

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