Department of Anatomy and Cell Biology, Western University, London, Canada.
Department of Biology, Concordia University, Montreal, Canada.
Elife. 2023 Oct 27;12:e81406. doi: 10.7554/eLife.81406.
an opportunistic human pathogen, poses a significant threat to human health and is associated with significant socio-economic burden. Current antifungal treatments fail, at least in part, because can initiate a strong drug tolerance response that allows some cells to grow at drug concentrations above their minimal inhibitory concentration. To better characterize this cytoprotective tolerance program at the molecular single-cell level, we used a nanoliter droplet-based transcriptomics platform to profile thousands of individual fungal cells and establish their subpopulation characteristics in the absence and presence of antifungal drugs. Profiles of untreated cells exhibit heterogeneous expression that correlates with cell cycle stage with distinct metabolic and stress responses. At 2 days post-fluconazole exposure (a time when tolerance is measurable), surviving cells bifurcate into two major subpopulations: one characterized by the upregulation of genes encoding ribosomal proteins, rRNA processing machinery, and mitochondrial cellular respiration capacity, termed the Ribo-dominant () state; and the other enriched for genes encoding stress responses and related processes, termed the Stress-dominant () state. This bifurcation persists at 3 and 6 days post-treatment. We provide evidence that the ribosome assembly stress response (RASTR) is activated in these subpopulations and may facilitate cell survival.
一种机会性人体病原体,对人类健康构成重大威胁,并与重大的社会经济负担有关。目前的抗真菌治疗至少在部分情况下会失败,因为 可以引发强烈的药物耐受反应,使一些细胞能够在药物浓度高于其最小抑制浓度的情况下生长。为了在分子单细胞水平上更好地描述这种细胞保护耐受程序,我们使用纳升液滴式转录组学平台对数千个单个真菌细胞进行了分析,并确定了它们在没有和存在抗真菌药物时的亚群特征。未处理细胞的图谱显示出与细胞周期阶段相关的异质表达,具有不同的代谢和应激反应。在氟康唑暴露后 2 天(可以测量耐受时),存活的细胞分为两个主要亚群:一个以核糖体蛋白、rRNA 加工机制和线粒体细胞呼吸能力的基因上调为特征,称为核糖体主导( )状态;另一个富含应激反应和相关过程的基因,称为应激主导( )状态。这种二分法在治疗后 3 天和 6 天持续存在。我们提供的证据表明,核糖体组装应激反应(RASTR)在这些亚群中被激活,可能有助于细胞存活。