Aspergillus fumigatus FhdA transcription factor is important for mitochondrial activity and codon usage regulation during the caspofungin paradoxical effect

<em>Aspergillus fumigatus </em>is the main etiological agent of aspergillosis. The antifungal drug caspofungin (CSP) can be used against <em>A. fumigatus</em> and CSP tolerance is observed. We have previously shown that the transcription factor FhdA is important for mitochondrial activity. Here, we show FhdA regulates genes transcribed by RNA polymerase II and III. FhdA influences the expression of tRNAs that are important for mitochondrial function upon CSP. Our results show a completely novel mechanism that is impacted by CSP.