FIG. 4.

The expression of six secreted A. fumigatus proteases is markedly reduced by deletion of prtT. Dormant conidia were incubated for 12, 24, 48, and 72 h in liquid SM medium at 37°C, after which total RNA was isolated and used in RT-PCR. Expression was determined by RT-PCR using primers shown in Table 1. Expression of prtT in the prtTΔ mutant strain was undetectable (prtT panel). RT-PCR with primers for gpdA, a housekeeping gene, was used as a control for the loading (gpdA panel). Three biological repeats of this experiment gave similar results.