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Protein kinase A signaling and calcium ions are major players in PAF mediated toxicity against Aspergillus niger.

ABSTRACT: The Penicillium chrysogenum antifungal protein PAF is toxic against potentially pathogenic Ascomycetes. We used the highly sensitive aequorin-expressing model Aspergillus niger to identify a defined change in cytoplasmic free Ca(2+) dynamics in response to PAF. This Ca(2+) signature depended on an intact positively charged lysine-rich PAF motif. By combining Ca(2+) measurements in A. niger mutants with deregulated cAMP/protein kinase A (PKA) signaling, we proved the interconnection of Ca(2+) perturbation and cAMP/PKA signaling in the mechanistic function of PAF. A deep understanding of the mode of action of PAF is an invaluable prerequisite for its future application as new antifungal drug.

SUBMITTER: Binder U

PROVIDER: S-EPMC4424949 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Protein kinase A signaling and calcium ions are major players in PAF mediated toxicity against Aspergillus niger.

Binder Ulrike U Benčina Mojca M Fizil Ádám Á Batta Gyula G Chhillar Anil K AK Marx Florentine F

FEBS letters 20150414 11

The Penicillium chrysogenum antifungal protein PAF is toxic against potentially pathogenic Ascomycetes. We used the highly sensitive aequorin-expressing model Aspergillus niger to identify a defined change in cytoplasmic free Ca(2+) dynamics in response to PAF. This Ca(2+) signature depended on an intact positively charged lysine-rich PAF motif. By combining Ca(2+) measurements in A. niger mutants with deregulated cAMP/protein kinase A (PKA) signaling, we proved the interconnection of Ca(2+) per ...[more]

PMID: 25882631

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