rpoD, RNA polymerase sigma factor RpoD
Also Known as
RPOD_ECOLI, rpoD, alt
Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. This sigma factor is the primary sigma factor during exponential growth. Preferentially transcribes genes associated with fast growth, such as ribosomal operons, other protein-synthesis related genes, rRNA- and tRNA-encoding genes and prfB. Interacts transiently with the RNA polymerase catalytic core formed by RpoA, RpoB, RpoC and RpoZ (2 alpha, 1 beta, 1 beta' and 1 omega subunit) to form the RNA polymerase holoenzyme that can initiate transcription. Identified in a complex containing RpoD, the RNA polymerase subunits RpoA, RpoB and RpoZ, CRP and DNA. Interacts with Rsd; this prevents interaction with the RNA polymerase catalytic core and with promoter DNA, and as a consequence, promotes transcription from promoters that require alternative sigma factors. Interacts with phage T4 AsiA; this interferes with binding to DNA and to the RNA polymerase.