title: RNA-mediated gene silencing in Candida albicans: inhibition of hyphae formation by use of RNAi technology.
abstract: The introduction of RNA silencing machinery in fungi has led to the promising application of RNAi methodology to knock down essential vital factor or virulence factor genes in the microorganisms. Efg1p is required for development of a true hyphal growth form which is known to be essential for interactions with human host cells and for the yeast's pathogenesis. In this paper, we describe the development of a system for presenting and studying the RNAi function on the EFG1 gene in C. albicans. The 19-nucleotide siRNA was designed on the basis of the cDNA sequence of the EFG1 gene in C. albicans and transfection was performed by use of a modified-PEG/LiAc method. To investigate EFG1 gene silencing in siRNA-treated cells, the yeasts were grown in human serum; to induce germ tubes a solid medium was used with the serum. Quantitative changes in expression of the EFG1 gene were analyzed by measuring the cognate EFG1 mRNA level by use of a quantitative real-time RT-PCR assay. Compared with the positive control, true hyphae formation was significantly reduced by siRNA at concentrations of 1 μM, 500 nM, and 100 nM (P < 0.05). In addition, siRNA at a concentration of 1 μM was revealed to inhibit expression of the EFG1 gene effectively (P < 0.05). On the basis of the potential of post-transcriptional gene silencing to control the expression of specific genes, these techniques may be regarded as promising means of drug discovery, with applications in biomedicine and functional genomics analysis.
authors.affiliation: Division of Molecular Biology, Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Moazeni
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Khoramizadeh
authors.forename: Parivash
authors.initials: P
authors.lastname: Kordbacheh
authors.forename: Zargham
authors.initials: Z
authors.lastname: Sepehrizadeh
authors.forename: Hojat
authors.initials: H
authors.lastname: Zeraati
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Noorbakhsh
authors.forename: Ladan
authors.initials: L
authors.lastname: Teimoori-Toolabi
authors.forename: Sassan
authors.initials: S
authors.lastname: Rezaie
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology; D001688:Biological Products / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D005656:Fungal Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D020869:Gene Expression Profiling; D006801:Humans; D025301:Hyphae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D034622:RNA Interference; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D014157:Transcription Factors / Q000037:antagonists & inhibitors* / Q000235:genetics
chemical_list: D000935:Antifungal Agents; D001688:Biological Products; D004268:DNA-Binding Proteins; C121438:EFG1 protein, Candida albicans; D005656:Fungal Proteins; D012331:RNA, Fungal; D034741:RNA, Small Interfering; D014157:Transcription Factors