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Published on: April 26, 2013
Molecular gymnastics: distortion of an RNA polymerase sigma factor
1Laboratory of Molecular and Cellular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, MD 20892-0830, USA. dhinton@helix.nih.gov
Abstract:
A recent structure obtained by nuclear magnetic resonance (NMR) spectroscopy shows that the binding of a small phage factor to the sigma(70) subunit of Escherichia coli RNA polymerase induces an unprecedented remodeling of a region of sigma(70), converting a DNA-binding helix-turn-helix into a continuous pseudohelix. This conformational change suggests how the phage factor can function both as an inhibitor and co-activator of transcription.
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