Analyzing the roles of the essential gene TRA1 and the novel extracellular vesicle EVP1 in regulating morphogenesis and the antifungal drug resistance response in the opportunistic fungal pathogen Candida albicans
Candida albicans is the leading cause of candidiasis, a systemic bloodstream infection with 40% mortality. The role of the essential gene TRA1 in C. albicans has not previously been studied. Using CRISPR strategies, we introduced three arginine to glutamine point mutations into TRA1, generating a tra1Q3 mutant. Phenotypic profiling of tra1Q3 revealed that the mutant is highly azole resistant, while subsequently demonstrating hypersensitivity to cell wall stressors, demonstrating an example of collateral sensitivities within fungi. RNA-seq analysis of tra1Q3 revealed 289 differentially expressed genes between tra1Q3 and the WT. From this data, we identified and further explored the gene Orf19.6741, which has not been studied in literature, and created a novel ΔOrf19.6741 knockout mutant Δevp1. Both tra1Q3 and Δevp1 demonstrated impaired filamentation and biofilm formation, antifungal sensitivity, and reduced macrophage evasion. Together, this work demonstrates the novel cellular roles of two previously uncharacterized genes in C. albicans.