title: Down-regulation of sidB gene by use of RNA interference in Aspergillus nidulans.
abstract: Introduction of the RNA interference (RNAi) machinery has guided the researchers to discover the function of essential vital or virulence factor genes in the microorganisms such as fungi. In the filamentous fungus Aspergillus nidulans, the gene sidB plays an essential role in septation, conidiation and vegetative hyphal growth. In the present study, we benefited from the RNAi strategy for down-regulating a vital gene, sidB, in the fungus A. nidulans.
  
  
  
  The 21-nucleotide small interfering RNA (siRNA) was designed based on the cDNA sequence of the sidB gene in A. nidulans. Transfection was performed through taking up siRNA from medium by 6 hour-germinated spores. To evaluate the morphologic effects of siRNA on the fungus, germ tube elongation was followed. Moreover, total RNA was extracted and quantitative changes in expression of the sidB gene were analyzed by measuring the cognate sidB mRNA level by use of a quantitative real-time RT-PCR assay.
  
  
  
  Compared to untreated-siRNA samples, a significant inhibition in germ tube elongation was observed in the presence of 25 nM of siRNA (42 VS 21 µM). In addition, at the concentration of 25 nM, a considerable decrease in sidB gene expression was revealed.
  
  
  
  Usage of RNAi as a kind of post-transcriptional gene silencing methods is a promising approach for designing new antifungal agents and discovering new drug delivery systems.
authors.affiliation: Dept. of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran. srezaie@tums.ac.ir.
authors.forename: Hamid
authors.initials: H
authors.lastname: Eslami
authors.affiliation: Dept. of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran. srezaie@tums.ac.ir.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Khorramizadeh
authors.affiliation: Dept. of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran. srezaie@tums.ac.ir.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Pourmand
authors.affiliation: Invasive Fungi Research Center/ Dept. of Medical Mycology and Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Moazeni
authors.affiliation: Dept. of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran. srezaie@tums.ac.ir.|Dept. of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Sassan
authors.initials: S
authors.lastname: Rezaie
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics*; D015536:Down-Regulation; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics*; D015870:Gene Expression; D034622:RNA Interference; D034741:RNA, Small Interfering; D014162:Transfection
chemical_list: D005656:Fungal Proteins; D034741:RNA, Small Interfering
keywords: Aspergillus nidulans; sidB; RNAi