Detection of RNase III inactive mutant.

<p><b>A: Verification of RNase III inactive mutant by RT-PCR.</b> Total RNA of cells was extract and used as the template to amplify the <i>rnc</i> gene. In <i>Δrnc</i> strain, the <i>rnc</i> mRNA could not be detected like WT and rncR because the kana gene was inserted into the <i>rnc</i> gene of <i>Δrnc</i> genome. 16s rRNA was used as the internal control. WT (wild type, <i>S. aureus</i> 8325-4), <i>Δrnc</i>(an RNase III inactivation mutant from 8325-4) and rncR (the restoration of RNase III activity in <i>Δrnc</i>). <b>B: The growth curves of </b><b><i>S. aureus</i></b><b> strains.</b> There is no significant difference between WT and <i>Δrnc</i>. WT: wild type, <i>S. aureus</i> 8325-4; <i>Δrnc</i>: an RNase III inactivation mutant from 8325-4. The experiment has been repeated for three times. <b>C: qRT-PCR quantification of the expression level of </b><b><i>spa</i></b>. The total RNA of the cells cultured for 6 h was extracted and the mRNA level of <i>spa</i> was detected by qRT-PCR. In the <i>Δrnc</i> strain, the level of <i>spa</i> mRNA was significantly increased compared with WT. WT: wild type, <i>S. aureus</i> 8325-4; <i>Δrnc</i>: an RNase III inactivation mutant from 8325-4; rncR: the restoration of RNase III activity in <i>Δrnc</i>. (**: P<0.01).