Comparison of the expression profiles of the Clostridium difficile 630E strain and a spoIIID mutant after 15h of growth

ABSTRACT: Compartment-specific control of gene expression during Bacillus subtilis sporulation is governed by a cascade of four sigma factors, sigmaF and sigmaG in the forespore and sigmaE and sigmaK in the mother cell. In this work, we combined transcriptional analyses and transcriptional start site mapping to define the sigmaF, sigmaE, sigmaG and sigmaK regulons in Clostridium difficile. A total of about 225 genes were under the control of these sigma factors: 25 in the sigmaF regulon, 97 sigmaE-dependent genes, 50 sigmaG-governed genes and 56 genes specifically controlled by sigmaK. A significant fraction of genes in each regulon are of unknown function and we can propose new candidates for spore coat proteins synthesized under the control of sigmaE and sigmaK among proteins previously detected in the spore proteome (Lawley et al., 2009 (PMID 19542279)). Global analysis of developmental gene expression under the control of these sigma factors indicate deviations from the B. subtilis model regarding the communication between mother cell and forespore in C. difficile. We show that the expression of the sigmaE regulon in the mother cell is not strictly under the control of sigmaF despite the fact that the forespore product SpoIIR is required for the processing of pro-sigmaE. In addition, the sigmaK regulon is not controlled by sigmaG in C. difficile in connection with the lack of pro-sigmaK processing in this bacterium. However, a control of the forespore on sigmaK targets is maintained through a sigmaF-dependent regulation of sigmaK-controlled genes, a process that bypasses sigmaG. We also performed a transcriptome experiment of the spoIIID mutant compared to the 630E strain and showed that SpoIIID represses the expression of SigE target genes and activates the expression of sigK. Transcriptional profiling of the C. difficile 630E strain vs. a spoIIID mutant after 15h of growth in MS. Two-condition experiment: 630E strain 15h vs. spoIIID mutant 15h. 2 biological replicates for each condition.

ORGANISM(S): [Clostridium] difficile

SUBMITTER: Monot Marc 

PROVIDER: E-GEOD-45689 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress