Silencing of mitochondrial alternative oxidase gene of Aspergillus fumigatus enhances reactive oxygen species production and killing of the fungus by macrophages

• Published in: Journal of bioenergetics and biomembranes 2008-12, Vol.40 (6), p.631-636
• Main Authors: Magnani, Taisa, Soriani, Frederico Marianetti, Martins, Vicente de Paulo, Policarpo, Anna Carolina de Freitas, Sorgi, Carlos Artério, Faccioli, Lúcia Helena, Curti, Carlos, Uyemura, Sérgio Akira
• Format: Article
• Language: English
• Subjects: Alternative oxidase; Animal Anatomy; Animal Biochemistry; Apoptosis - physiology; Aspergillus fumigatus; Aspergillus fumigatus - cytology; Aspergillus fumigatus - genetics; Aspergillus fumigatus - metabolism; Biochemistry; Bioorganic Chemistry; Cells, Cultured; Chemistry; Chemistry and Materials Science; Enzymes; Fungi; Gene Silencing; Genes; Histology; Humans; Macrophage killing; Macrophages - immunology; Mitochondria; Mitochondria - enzymology; Mitochondrial Proteins; Morphology; Organic Chemistry; Oxidative stress; Oxidoreductases - genetics; Oxidoreductases - metabolism; Paraquat; Pathogens; Plant Proteins; Reactive Oxygen Species - metabolism; RNAi; Spores, Fungal
• ISSN: 0145-479X; 1573-6881
• DOI: 10.1007/s10863-008-9191-5

We previously demonstrated that conidia from Aspergillus fumigatus incubated with menadione and paraquat increases activity and expression of cyanide-insensitive alternative oxidase (AOX). Here, we employed the RNA silencing technique in A. fumigatus using the vector pALB1/aoxAf in order to down-regulate the aox gene. Positive transformants for aox gene silencing of A. fumigatus were more susceptible both to an imposed in vitro oxidative stress condition and to macrophages killing, suggesting that AOX is required for the A. fumigatus pathogenicity, mainly for the survival of the fungus conidia during host infection and resistance to reactive oxygen species generated by macrophages.