Functional interaction between RNA polymerase alpha subunit C-terminal domain and sigma70 in UP-element- and activator-dependent transcription
Chen, H.; Tang, H.; Ebright, R.H.
Molecular Cell 11(6): 1621-1633
ISSN/ISBN: 1097-2765 PMID: 12820974 DOI: 10.1016/s1097-2765(03)00201-6
We show that the Escherichia coli RNA polymerase (RNAP) alpha subunit C-terminal domain (alphaCTD) functionally interacts with sigma(70) at a subset of UP-element- and activator-dependent promoters, we define the determinants of alphaCTD and sigma(70) required for the interaction, and we present a structural model for the interaction. The alphaCTD-sigma(70) interaction spans the upstream promoter and core promoter, thereby linking recognition of UP-elements and activators in the upstream promoter with recognition of the -35 element in the core promoter. We propose that the alphaCTD-sigma(70) interaction permits UP-elements and activators not only to "recruit" RNAP through direct interaction with alphaCTD, but also to "remodel" RNAP-core-promoter interaction through indirect, alphaCTD-bridged interactions with sigma(70).