Archaeal TFEα/β is a hybrid of TFIIE and the RNA polymerase III subcomplex hRPC62/39
- University College London, United Kingdom
- Max Planck Institute for Terrestrial Microbiology, Germany
Abstract
Transcription initiation of archaeal RNA polymerase (RNAP) and eukaryotic RNAPII is assisted by conserved basal transcription factors. The eukaryotic transcription factor TFIIE consists of α and β subunits. Here we have identified and characterised the function of the TFIIEβ homologue in archaea that on the primary sequence level is related to the RNAPIII subunit hRPC39. Both archaeal TFEβ and hRPC39 harbour a cubane 4Fe-4S cluster, which is crucial for heterodimerization of TFEα/β and its engagement with the RNAP clamp. TFEα/β stabilises the preinitiation complex, enhances DNA melting, and stimulates abortive and productive transcription. These activities are strictly dependent on the β subunit and the promoter sequence. Our results suggest that archaeal TFEα/β is likely to represent the evolutionary ancestor of TFIIE-like factors in extant eukaryotes.
Article and author information
Author details
Reviewing Editor
- Patrick Cramer, Max Planck Institute for Biophysical Chemistry, Germany
Version history
- Received: April 28, 2015
- Accepted: June 11, 2015
- Accepted Manuscript published: June 12, 2015 (version 1)
- Version of Record published: July 8, 2015 (version 2)
Copyright
© 2015, Blombach et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Archaeal TFEα/β is a hybrid of TFIIE and the RNA polymerase III subcomplex hRPC62/39
eLife 4:e08378.
https://doi.org/10.7554/eLife.08378
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