title: cyp51A gene silencing using RNA interference in azole-resistant Aspergillus fumigatus.
abstract: An increasing number of reports have described the emergence of acquired resistance of Aspergillus fumigatus to azole compounds. The primary mechanism of resistance in clinical isolates is the mutation of the azole drug target enzyme, which is encoded by the cyp51A gene. The aim of this study was to evaluate the impact of silencing the cyp51A gene in azole-resistant A. fumigatus isolates. A 21-nucleotide small-interfering RNA (siRNA) was designed based on the cDNA sequence of the A. fumigatus cyp51A gene. After silencing the cyp51A gene in germinated conidia (15, 20, 25 and 50 nM), azole-resistant A. fumigatus was cultured on broth media and gene expression was analysed by measuring the cyp51A mRNA level using RT-PCR assay. Hyphae were successfully transfected by siRNA and expression of the cyp51A gene was significantly reduced by siRNA at the concentration of 50 nM (P ≤ 0.05). In addition, at this siRNA concentration, the minimum inhibitory concentration of itraconazole for the treated cells was decreased, compared with that for untreated control cells, from 16 to 4 μg/ml.
authors.affiliation: Department of Medical Mycology and parasitology/Invasive Fungi Research Center, School of Medicine Mazandaran University of Medical Sciences Sari, Sari, Iran.
authors.forename: Bita
authors.initials: B
authors.lastname: Mousavi
authors.affiliation: Department of Medical Mycology and parasitology/Invasive Fungi Research Center, School of Medicine Mazandaran University of Medical Sciences Sari, Sari, Iran.
authors.forename: Mohammad T
authors.initials: MT
authors.lastname: Hedayati
authors.affiliation: Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Ladan
authors.initials: L
authors.lastname: Teimoori-Toolabi
authors.affiliation: ENVA UPEC Dynamyc Research Group, Ecole nationale veterinaire d'Alfort, University Paris Est Creteil, Maisons Alfort, Creteil, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Guillot
authors.affiliation: Department of Epidemiology and Reproductive Health, Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.|Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ahad
authors.initials: A
authors.lastname: Alizadeh
authors.affiliation: Department of Medical Mycology and parasitology/Invasive Fungi Research Center, School of Medicine Mazandaran University of Medical Sciences Sari, Sari, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Badali
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001232:Aspergillus fumigatus / Q000187:drug effects* / Q000235:genetics*; D001393:Azoles / Q000494:pharmacology*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics; D025141:Drug Resistance, Fungal / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D025301:Hyphae / Q000187:drug effects / Q000235:genetics; D017964:Itraconazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D009154:Mutation; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D014162:Transfection
chemical_list: D000935:Antifungal Agents; D001393:Azoles; D018076:DNA, Complementary; D005656:Fungal Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D017964:Itraconazole; D003577:Cytochrome P-450 Enzyme System; C465526:cytochrome P-450 CYP51A, Aspergillus
keywords: Aspergillus fumigatus; Azole resistance; RNAi; cyp51A gene