Figure 2. Expression of Mma mgtC and upstream genes in high Mg²⁺ and low Mg²⁺ conditions.

(A) RT-PCR experiment on RNA isolated from M. marinum strains grown in high or low Mg²⁺ with primers specific for mgtC, MMAR_2686, MMAR_2683 (PPE31) and sigA. Experiment was carried out with wild-type strain, mgtC mutant strain and complemented strain. Controls where reverse transcriptase was omitted (indicated by RT -) are done to verify the absence of genomic DNA contamination in the RNA sample. The sigA gene is used as control. (B) Quantification of mgtC, MMAR_2686 and MMAR_2683 RNA by Q-RT-PCR experiment using RNA isolated from M. marinum strains grown in high or low Mg²⁺. The sigma factor sigA was used as an internal standard. Results are expressed as means+standard deviations (SD) from a representative experiment performed in triplicate.