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The Flo8 transcription factor is essential for hyphal development and virulence in Candida albicans. Mol Biol Cell

State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
Molecular Biology of the Cell (Impact Factor: 4.55). 02/2006; 17(1):295-307. DOI: 10.1091/mbc.E05-06-0502
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ABSTRACT The transcription factor Flo8 is essential for filamentous growth in Saccharomyces cerevisiae and is regulated under the cAMP/protein kinase A (PKA) pathway. To determine whether a similar pathway/regulation exists in Candida albicans, we have cloned C. albicans FLO8 by its ability to complement S. cerevisiae flo8. Deleting FLO8 in C. albicans blocked hyphal development and hypha-specific gene expression. The flo8/flo8 mutant is avirulent in a mouse model of systemic infection. Genome-wide transcription profiling of efg1/efg1 and flo8/flo8 using a C. albicans DNA microarray suggests that Flo8 controls subsets of Efg1-regulated genes. Most of these genes are hypha specific, including HGC1 and IHD1. We also show that Flo8 interacts with Efg1 in yeast and hyphal cells by in vivo immunoprecipitation. Similar to efg1/efg1, flo8/flo8 and cdc35/cdc35 show enhanced hyphal growth under an embedded growth condition. Our results suggest that Flo8 may function downstream of the cAMP/PKA pathway, and together with Efg1, regulates the expression of hypha-specific genes and genes that are important for the virulence of C. albicans.

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    • "Cells lacking any of these repressors constitutively grow as long pseudohyphae, as the expression of hyphal-specific genes is not inhibited (Kadosh and Johnson, 2005; Murad et al., 2001; Sudbery, 2011). The up-regulation of the expression of hyphal-specific genes is accomplished by several transcription factors, including Efg1, Chp1, Cph2, Tec1, Flo8, Czf1, Rim101 and Ndt80 (Shapiro et al., 2011; Sudbery, 2011; Stoldt et al., 1997; Lane et al., 2001; Cao et al., 2006; Davis et al., 2000; Sellam et al., 2010). Efg1 is necessary for the formation of hyphae in response to serum, neutral pH, CO 2 and GlcNAc in liquid media and on solid spider media. "
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    Fungal Genetics and Biology 07/2013; 60. DOI:10.1016/j.fgb.2013.07.001 · 3.26 Impact Factor
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    • "Consistent with the phenotype observed in the bcr1/ bcr1 cyr1/cyr1 double mutant, two major transcription regulators downstream of cAMP signalling, Efg1 and Flo8, are also required for hyper-filamentation of the bcr1/bcr1 mutant. Filamentous-specific G1 cyclin-related protein Hgc1 is transcriptionally regulated by the cAMP pathway and the Efg1 and Flo8 transcription regulators (Zheng and Wang, 2004; Cao et al., 2006). HGC1 is essential for opaque cell filamentation in the bcr1/bcr1 mutant (Fig. 8A). "
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    Molecular Microbiology 06/2013; DOI:10.1111/mmi.12310 · 5.03 Impact Factor
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    • "Well-established DNA array technology allows efficient analysis of the genome-wide expression of multiple strains, mutants and different growth conditions. Much work has been published about issues such as the yeast-to-hypha transition (Nantel et al. 2002), cyclic AMP signalling (Harcus et al. 2004), the regulation of morphogenesis and metabolism by APSES proteins (Doedt et al. 2004), the role of the FLO8 transcription factor in hyphal development (Cao et al. 2006), the convergent regulation of virulence by Cph1p, Cph2p and Efg1p (Lane et al. 2001), the Tac1p regulon (Liu et al. 2007), the response to steroids (Banerjee et al. 2007), etc. Despite such a large body of information, we still lack the transcriptomes of C. albicans obtained under standard and well defined sets of conditions. "
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