title: Candida albicans ferric reductase FRP1 is regulated by direct interaction with Rim101p transcription factor.
abstract: The opportunistic pathogen Candida albicans develops different systems to acquire essential nutrients such as iron. The Rim101 pathway controls gene expression to adapt to different environments through transcription factor Rim101p. Ferric reductase genes are important for iron acquisition, but further work should be carried out to show about how ferric reductase genes are regulated. In this study we demonstrate that ferric reductase FRP1 expression is upregulated by alkaline pH and iron-limited conditions. Moreover, promoter deletion identified that the upregulated elements lie in -822 to 437 and 263 to -124 and the downregulated elements in -437 to -263 using a beta-galactosidase reporter system. Using electrophoretic mobility shift assay we also found that Rim101p can bind directly with two putative 5'-CCAAGAA-3' sites at the -157 and -629 sites. Interestingly, site-specific mutations show that only the -629 site, not the -157 site, plays an important role in FRP1 expression under iron-limited conditions.
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, Nankai University, Tianjin, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liang
authors.forename: Lei
authors.initials: L
authors.lastname: Gui
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Wei
authors.forename: Wen
authors.initials: W
authors.lastname: Zheng
authors.forename: Lai-Jun
authors.initials: LJ
authors.lastname: Xing
authors.forename: Ming-Chun
authors.initials: MC
authors.lastname: Li
mesh_terms: D000468:Alkalies / Q000378:metabolism; D019677:Artificial Gene Fusion; D002176:Candida albicans / Q000201:enzymology* / Q000502:physiology*; D004271:DNA, Fungal / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D038181:FMN Reductase / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D017930:Genes, Reporter; D007501:Iron / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D000468:Alkalies; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C489602:RIM101 protein, Candida albicans; D007501:Iron; D038181:FMN Reductase; C023903:ferric citrate iron reductase; D001616:beta-Galactosidase