The Role of α-CTD in the Genome-Wide Transcriptional Regulation of the <i>Bacillus subtilis</i> Cells

<div><p>The amino acid sequence of the RNA polymerase (RNAP) α-subunit is well conserved throughout the Eubacteria. Its C-terminal domain (α-CTD) is important for the transcriptional regulation of specific promoters in both <i>Escherichia coli</i> and <i>Bacillus subtilis</i>, through interactions with transcription factors and/or a DNA element called the “UP element”. However, there is only limited information regarding the α-CTD regulated genes in <i>B</i>. <i>subtilis</i> and the importance of this subunit in the transcriptional regulation of <i>B</i>. <i>subtilis</i>. Here, we established strains and the growth conditions in which the α-subunit of RNAP was replaced with a C-terminally truncated version. Transcriptomic and ChAP-chip analyses revealed that α-CTD deficiency reduced the transcription and RNAP binding of genes related to the utilization of secondary carbon sources, transition state responses, and ribosome synthesis. In <i>E</i>. <i>coli</i>, it is known that α-CTD also contributes to the expression of genes related to the utilization of secondary carbon sources and ribosome synthesis. Our results suggest that the biological importance of α-CTD is conserved in <i>B</i>. <i>subtilis</i> and <i>E</i>. <i>coli</i>, but that its specific roles have diversified between these two bacteria.</p>