The pyruvate dehydrogenase kinase 2 (PDK2) is associated with conidiation, mycelial growth, and pathogenicity in Fusarium graminearum

Abstract

Abstract Pyruvate dehydrogenase kinase (PDK) is a mitochondrial enzyme in a variety of eukaryotes, including the plant pathogen Fusarium graminearum. This enzyme can reduce the oxidation of glucose to acetyl-coA by phosphorylation and selectively inhibits the activity of pyruvate dehydrogenase (PDH), which is a kind of pyruvate dehydrogenase complex (PDC). In this study, we investigated the F. graminearum pyruvate dehydrogenase kinase encoded by FgPDK2, which is a homologue of Neurospora crassa PDK2. The disruption of the FgPDK2 gene led to several phenotypic defects including effects on mycelial growth, conidiation, pigmentation, and pathogenicity. The mutants also showed decreased resistance to osmotic stress and cell membrane/wall-damaging agents. The FgPDK2 deletion mutant exhibited reduced virulence. All of these defects were restored by genetic complementation of the mutant with the complete FgPDK2 gene. Overall, the results demonstrated that FgPDK2 is crucial for the growth of F. graminearum and can be exploited as a potential molecular target for novel fungicides to control Fusarium head blight caused by F. graminearum. Graphical abstract