Aspergillus fumigatus calcineurin interacts with a nucleoside diphosphate kinase

The Ca²⁺-calcineurin pathway affects virulence and morphogenesis in filamentous fungi. Here, we identified 37 CalA-interacting proteins that interact with the catalytic subunit of calcineurin (CalA) in Aspergillus fumigatus, including the nucleoside diphosphate kinase (SwoH). The in vivo interaction between CalA and SwoH was validated by bimolecular fluorescence complementation. A. fumigatus swoH is an essential gene. Therefore, a temperature-sensitive conditional mutant strain with a point mutation in the active site, SwoH^V83F, was constructed, which demonstrated reduced growth and increased sensitivity to elevated temperatures. The SwoH^V83F mutation did not cause a loss in virulence in the Galleria mellonella infection model. Taken together these results imply that CalA interacts with SwoH.