白色-不透明转换的转录调控以及环境线索和菌株背景的调节作用
Transcriptional control of white-opaque switching and modulation by environmental cues and strain background.
作者信息
Sharma Anupam, Homayoon Ameen, Weyler Michael, Frazer Corey, Ramírez-Zavala Bernardo, Morschhäuser Joachim, Bennett Richard J
机构信息
Department of Molecular and Microbiology and Immunology, Brown University, Providence, Rhode Island, USA.
Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Bavaria, Germany.
出版信息
mBio. 2025 May 14;16(5):e0058125. doi: 10.1128/mbio.00581-25. Epub 2025 Apr 9.
The opportunistic fungal pathogen can undergo cellular transitions in response to environmental cues that impact its lifestyle and its interactions with the human host. This is exemplified by the white-opaque switch, which is a heritable transition between two phenotypic states that is regulated by a highly interconnected network of transcription factors (TFs). To obtain greater understanding of the transcriptional regulation of the switch, we generated a genome-wide, tetracycline-inducible TF library in the WO-1 strain background and identified those TFs whose forced expression induces white cells to switch to the opaque state. This set of opaque-inducing TFs was also evaluated for their ability to induce switching in a second strain background, that of the standard reference strain SC5314, as well as during growth on different laboratory media. These experiments identify 14 TFs that can drive white-to-opaque switching when overexpressed but that do so in a highly strain- and media-specific manner. In particular, changes in pH, amino acids, and zinc concentrations had marked effects on the ability of TFs to drive phenotypic switching. These results provide insights into the complex transcriptional regulation of switching in and reveal that an interplay between genetic and environmental factors determines TF function and cell fate.IMPORTANCEThe white-opaque switch in represents a model system for understanding an epigenetic switch in a eukaryotic pathogen. Here, we generated an inducible library of the set of transcription factors (TFs) present in and identify 14 TFs that can drive the white-to-opaque transition when ectopically expressed. We demonstrate that several of these TFs induce the switch in a highly strain- and media-specific manner. This highlights that both strain background and changes in experimental conditions (including different water sources) can profoundly impact the phenotypic consequences of TF overexpression. Moreover, the inducible TF library provides an invaluable tool for the further analysis of TF function in this important human pathogen.
机会性真菌病原体可根据影响其生活方式及其与人类宿主相互作用的环境线索进行细胞转变。白色-不透明转换就是一个例子,它是两种表型状态之间的可遗传转变,由一个高度互联的转录因子(TFs)网络调控。为了更深入了解这种转换的转录调控,我们在WO-1菌株背景下构建了一个全基因组的、四环素诱导型TF文库,并鉴定出那些强制表达能诱导白色细胞转变为不透明状态的TFs。还评估了这组诱导不透明的TFs在第二个菌株背景(标准参考菌株SC5314)中以及在不同实验室培养基上生长时诱导转换的能力。这些实验确定了14个TFs,它们在过表达时可驱动白色到不透明的转换,但这种转换具有高度的菌株和培养基特异性。特别是,pH值、氨基酸和锌浓度的变化对TFs驱动表型转换的能力有显著影响。这些结果为白色念珠菌转换的复杂转录调控提供了见解,并揭示了遗传和环境因素之间的相互作用决定了TF功能和细胞命运。
重要性
白色念珠菌中的白色-不透明转换代表了一个用于理解真核病原体中表观遗传转换的模型系统。在此,我们构建了白色念珠菌中存在的转录因子(TFs)的诱导型文库,并鉴定出14个TFs,它们在异位表达时可驱动白色到不透明的转变。我们证明其中几个TFs以高度菌株和培养基特异性的方式诱导转换。这突出表明菌株背景和实验条件的变化(包括不同的水源)都可深刻影响TF过表达的表型后果。此外,诱导型TF文库为进一步分析这种重要人类病原体中TF的功能提供了一个宝贵工具。