RNA polymerase (RNAP) is an extensively studied multisubunit enzyme required for transcription of DNA into RNA, yet the δ subunit of RNAP remains an enigmatic protein whose physiological roles have not been fully elucidated. Here, we identify a novel, so far unrecognized function of δ from Bacillus subtilis. We demonstrate that δ affects the regulation of RNAP by the concentration of the initiating nucleoside triphosphate ([iNTP]), an important mechanism crucial for rapid changes in gene expression in response to environmental changes. Consequently, we demonstrate that δ is essential for cell survival when facing a competing strain in a changing environment. Hence, although δ is not essential per se, it is vital for the cell's ability to rapidly adapt and survive in nature. Finally, we show that two other proteins, GreA and YdeB, previously implicated to affect regulation of RNAP by [iNTP] in other organisms, do not have this function in B. subtilis.

• MeSH
• Bacillus subtilis enzymology   genetics   physiology   MeSH
• Bacterial Proteins chemistry   genetics   metabolism   MeSH
• DNA-Directed RNA Polymerases chemistry   genetics   metabolism   MeSH
• Gene Expression MeSH
• Adaptation, Physiological MeSH
• Transcription, Genetic MeSH
• Gene Knockout Techniques MeSH
• Microbial Viability MeSH
• Protein Subunits MeSH
• Promoter Regions, Genetic genetics   MeSH
• Gene Expression Regulation, Bacterial genetics   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Bacterial Proteins MeSH
• DNA-Directed RNA Polymerases MeSH
• Protein Subunits MeSH