Essential Gene Identification and Drug Target Prioritization in Aspergillus fumigatus

作者：Wenqi Hu, Susan Sillaots, Sébastien Lemieux, John Davison, Sarah Kauffman, Anouk Breton, Annie Linteau, Chunlin Xin, Joel C. Bowman, Jeff Becker, Bo Jiang, Terry Roemer · 发表于：PLoS Pathogens · 年份：2007 · DOI：10.1371/journal.ppat.0030024 · 被引用次数：246 · 研究领域：Antifungal resistance and susceptibility、Fungal Biology and Applications、Microbial Natural Products and Biosynthesis

Aspergillus fumigatus is the most prevalent airborne filamentous fungal pathogen in humans, causing severe and often fatal invasive infections in immunocompromised patients. Currently available antifungal drugs to treat invasive aspergillosis have limited modes of action, and few are safe and effective. To identify and prioritize antifungal drug targets, we have developed a conditional promoter replacement (CPR) strategy using the nitrogen-regulated A. fumigatus NiiA promoter (pNiiA). The gene essentiality for 35 A. fumigatus genes was directly demonstrated by this pNiiA-CPR strategy from a set of 54 genes representing broad biological functions whose orthologs are confirmed to be essential for growth in Candida albicans and Saccharomyces cerevisiae. Extending this approach, we show that the ERG11 gene family (ERG11A and ERG11B) is essential in A. fumigatus despite neither member being essential individually. In addition, we demonstrate the pNiiA-CPR strategy is suitable for in vivo phenotypic analyses, as a number of conditional mutants, including an ERG11 double mutant (erg11BDelta, pNiiA-ERG11A), failed to establish a terminal infection in an immunocompromised mouse model of systemic aspergillosis. Collectively, the pNiiA-CPR strategy enables a rapid and reliable means to directly identify, phenotypically characterize, and facilitate target-based whole cell assays to screen A. fumigatus essential genes for cognate antifungal inhibitors.