GSE75080
Transcriptome analysis of the C. glutamicum deletion mutant of rnc, which encodes an RNase III homolog
The Corynebacterium glutamicum R cgR_1959 gene encodes an endoribonuclease of the RNase III family. Deletion mutant of cgR_1959 (?rnc mutant) showed an elongated cell shape, and presence of several lines on the cell surface, indicating a required of RNase III for maintaining normal cell morphology in C. glutamicum. The level of mraZ mRNA was increased, whereas cgR_1596 mRNA encoding a putative cell wall hydrolase  and ftsEX mRNA were decreased in the ?rnc mutant. The half-life of mraZ mRNA was significantly prolonged in the ?rnc and the ?pnp mutant strains. This indicated that the degradation of mraZ mRNA was performed by RNase III and the 3'-to-5' exoribonuclease, PNPase. Northern hybridization and primer extension analysis revealed that the cleavage site for mraZ mRNA by RNase III is in the coding region. Overproduction of MraZ resulted in an elongated cell shape. The expression of ftsEX decreased while that of cgR_1596 unchanged in an MraZ-overexpressing strain. An electrophoretic mobility shift assay and a transcriptional reporter assay indicate that MraZ is a transcriptional repressor of ftsEX in C. glutamicum. These results indicate that RNase III is required for efficient expression of MraZ-dependent ftsEX and MraZ-independent cgR_1596. Overall design: Gene expression profile of the wild type at the exponential phase was compared with that of the rnc mutant. Three indepent experiments were performed.