From specialist to generalist: biotic and abiotic and reservoirs of fungal pathogens

许多真菌病原体具有广泛的宿主范围，长寿命的环境阶段，和腐生性生长的潜力。这种类型的病原体需要新的模型，以提高我们理解这种独特，多样和丰富的病原体组的动态和影响的能力。该项目的总体目标是扩大我们对新兴真菌病原体在宿主内外的动态的理解。将进行实验室和现场实验和现场调查，以开发和适应疾病模型，利用两栖动物壶菌，Batrachochytrium dendrobatim（Bd），作为主要的模型系统。最近的证据表明，Bd可以感染各种各样的生物（除了两栖动物），Bd有能力形成生物膜（这可能会提高其环境持久性的潜力），使其成为该项目的理想模型系统。将开发真菌疾病模型并将其参数化，包括通用病原体、外部病原体储库（包括将病原体并入生物膜的可能性）以及腐生性病原体生长的潜力。这些模型将被用来探讨这些功能的真菌病原体的病原体流行和疾病的严重程度在目标宿主物种的影响，在两栖动物/Bd系统和其他新兴的真菌病原体系统。具体而言，研究小组将（1）对Bd可能在宿主外持续存在的替代宿主和环境宿主进行深入分析，（2）通过实验测试这些替代宿主和环境宿主对Bd生存和繁殖的作用，Bd在环境中的持久性，以及病原体向两栖动物的传播，（3）测试Bd生物膜的形成如何影响Bd的持久性和繁殖，（4）探索Bd生物膜在极端环境中的持久性（即温度），如果这影响了使用新方法的Bd的感染性（宏基因组学，元转录组学，元蛋白质组学），（5）改进基于真菌的疾病模型，以包括使用Bd作为案例研究的以生态系统为中心的方法，以及（6）创建新兴的真菌数据库，进行元分析，并将我们的疾病模型与其他新出现的真菌疾病相匹配。

Many fungal pathogens have broad host ranges, long-lived environmental stages, and the potential for saprotrophic growth. New models are needed for this type of pathogen, in order to improve our ability to understand the dynamics and impacts of this unique, diverse, and abundant group of pathogens. The overall aim of this project is to expand our understanding of the dynamics of emerging fungal pathogens both amongst and outside of their hosts. Laboratory and field experiments and field surveys will be conducted to develop and fit disease models, utilizing the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), as the primary model system. Recent evidence that Bd can infect a wide diversity of organisms (in addition to amphibians), and that Bd has the ability to form biofilms (which may enhance its potential for environmental persistence), makes this an ideal model system for this project. Fungal disease models will be developed and parameterized, including generalist pathogens, external pathogen reservoirs (including the possibility of incorporation of the pathogen into biofilms), and the potential for saprotrophic pathogen growth. The models will be used to explore the implications of these features of fungal pathogens on pathogen prevalence and disease severity in target host species, in the both the amphibian/Bd system and in other emerging fungal pathogen systems. Specifically, the research team will (1) perform an in-depth analysis of alternative hosts and environmental reservoirs where Bd may persist outside of the host, (2) test experimentally the role of these alternative hosts and environmental reservoirs on survival and reproduction of Bd, persistence of Bd in the environment, and in transmission of the pathogen to amphibians, (3) test how Bd biofilm formation affects Bd persistence and reproduction, (4) explore how Bd biofilms persist in extreme environments (i.e. temperatures) and if this affects the infectiousness of Bd using novel approaches (metagenomics, meta-transcriptomics, meta-proteomics), (5) improve the fungal-based disease model to include an ecosystem-centric approach using Bd as a case study, and (6) create an emerging fungal database, conduct a metanalysis, and fit our disease models to other emerging fungal diseases.