Functions of the aconitase family in Fusarium proliferatum

Abstract:

[Objective] Fusarium proliferatum is one of the major pathogens causing root rot of alfalfa. This study aims to investigate the function of the aconitase family in F. proliferatum and give insights into the molecular mechanisms underlying the physiological metabolism of this pathogen. [Methods] We employed the hmmsearch tool to identify the proteins containing the aconitase domain in F. proliferatum and then carried out the phylogenetic analysis. real-time PCR and SWISS-MODEL were employed to analyze the expression profiles of FpACO genes and the protein structures, respectively. The homologous recombination method was used to construct the FpACO-deleted mutants of F. proliferatum. Furthermore, we explored the growth, sporulation, spore morphology, stress responses, and pathogenicity of ΔFpACO3, ΔFpACO4-1, and ΔFpACO4-2 and measured the mitochondrial metabolism indicators of the mutants. [Results] FpACO4-1 and FpACO4-2 were involved in sporulation and spore morphogenesis. FpACO3, FpACO4-1, and FpACO4-2 were responsible for regulating the sensitivity of F. proliferatum to cell wall stress and metal ion stress. Moreover, FpACO3, FpACO4-1, and FpACO4-2 affected the mitochondrial metabolism indicators, including the total aconitase activity, the ATP level, the hydrogen peroxide level, and the expression of key genes in the tricarboxylic acid cycle. [Conclusion] The aconitase family members are involved in the regulation of the processes such as sporulation, spore morphogenesis, response to cell wall stress and metal ion stress, and mitochondrial metabolism in F. proliferatum.