Related Experiment Video
Updated: Jul 10, 2026

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
Structural biology of RNA polymerase III: mass spectrometry elucidates subcomplex architecture
Kristina Lorenzen1, Alessandro Vannini, Patrick Cramer
1Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Chemistry, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands.
Abstract:
RNA polymerases (Pol) II and III synthesize eukaryotic mRNAs and tRNAs, respectively. The crystal structure of the 12 subunit Pol II is known, but only limited structural information is available for the 17 subunit Pol III. Using mass spectrometry (MS), we correlated masses of Pol II complexes with the Pol II structure. Analysis of Pol III showed that the complete enzyme contains a single copy of each subunit and revealed a 15 subunit form lacking the Pol III-specific subcomplex C53/37. DMSO treatment dissociated the C17/25 heterodimer of Pol III, confirming a peripheral location as its counterpart in Pol II. Tandem MS revealed the Pol III-specific subunits C82 and C34 dissociating as a heterodimer. C11 was retained, arguing against a stable trimeric subcomplex, C53/37/11. These data suggest that Pol III consists of a 10 subunit Pol II-like core; the peripheral heterodimers C17/25, C53/37, and C82/34; and subunit C31, which bridges between C82/34, C17/25, and the core.
More Related Videos
10:01Combining Chemical Cross-linking and Mass Spectrometry of Intact Protein Complexes to Study the Architecture of Multi-subunit Protein Assemblies
Published on: November 28, 2017
14:58Identification of Protein Complexes in Escherichia coli using Sequential Peptide Affinity Purification in Combination with Tandem Mass Spectrometry
Published on: November 12, 2012
Related Concept Videos
Eukaryotic RNA Polymerases
All three eukaryotic RNAPs require specific transcription factors, of which the...
Eukaryotic RNA Polymerases
All three eukaryotic RNAPs require specific transcription factors, of which the...
Transcription Initiation
The promoters and enhancers and their accessory proteins allow tight regulation of...
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
RNA Polymerase II Accessory Proteins