title: Differential roles of pyruvate decarboxylase in aerial and embedded mycelia of the ascomycete Gibberella zeae.
abstract: The pyruvate-acetaldehyde-acetate (PAA) pathway has diverse roles in eukaryotes. Our previous study on acetyl-coenzyme A synthetase 1 (ACS1) in Gibberella zeae suggested that the PAA pathway is important for lipid production, which is required for perithecia maturation. In this study, we deleted all three pyruvate decarboxylase (PDC) genes, which encode enzymes that function upstream of ACS1 in the PAA pathway. Results suggest PDC1 is required for lipid accumulation in the aerial mycelia, and deletion of PDC1 resulted in highly wettable mycelia. However, the total amount of lipids in the PDC1 deletion mutants was similar to that of the wild-type strain, likely due to compensatory lipid production processes in the embedded mycelia. PDC1 was expressed both in the aerial and embedded mycelia, whereas ACS1 was observed only in the aerial mycelia in a PDC1-dependent manner. PDC1 is also involved in vegetative growth of embedded mycelia in G. zeae, possibly through initiating the ethanol fermentation pathway. Thus, PDC1 may function as a key metabolic enzyme crucial for lipid production in the aerial mycelia, but play a different role in the embedded mycelia, where it might be involved in energy generation by ethanol fermentation.
authors.affiliation: Department of Agricultural Biotechnology, Center for Fungal Pathogenesis, Seoul National University, Seoul, Korea.
authors.forename: Hokyoung
authors.initials: H
authors.lastname: Son
authors.forename: Kyunghun
authors.initials: K
authors.lastname: Min
authors.forename: Jungkwan
authors.initials: J
authors.lastname: Lee
authors.forename: Gyung Ja
authors.initials: GJ
authors.lastname: Choi
authors.forename: Jin-Cheol
authors.initials: JC
authors.lastname: Kim
authors.forename: Yin-Won
authors.initials: YW
authors.lastname: Lee
mesh_terms: D000431:Ethanol / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005874:Gibberella / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D050356:Lipid Metabolism; D053858:Metabolic Networks and Pathways; D025282:Mycelium / Q000145:classification / Q000201:enzymology / Q000378:metabolism*; D011767:Pyruvate Decarboxylase / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins; D000431:Ethanol; D011767:Pyruvate Decarboxylase