Anthraquinone evolution in lichenised fungi

“生活在沙漠和高海拔地区的地衣真菌面临着强烈紫外线的挑战，众所周知，紫外线会导致DNA损伤。最近，我们已经证明，在近1000个物种的子囊菌科中，终裂菌科（Teloschistales）经历了100万年的适应性辐射，其中四科之一的终裂菌科经历了从树皮到岩石以及从背阴到阳光暴露的栖息地的转换，从而增加了多样化率。我们的假设是，对阳光充足的栖息地的适应可能是由同一时期关键的新型表型创新实现的：蒽醌的产生，这是一种次生代谢物，已知可以抵御紫外线。因此，两个生态因素（阳光照射和岩石基质）和表型创新（蒽醌类）似乎可能是端裂科（大型地衣形成真菌谱系之一）成功的原因。目的：1)重建远裂门及其姐妹分支的基因组水平系统发育，以测试当前分类群是否为单系，并反映分支/物种形成率变化等进化过程；ii)对次生代谢物生物合成基因簇进行注释，检验蒽醌生物合成的新表型创新是否与新基因簇的进化有关；iii)测试哪些因素控制了端裂鱼的代谢组变化，例如系统发育、气候条件（特别是太阳辐射水平和干旱程度）、底物偏好和地理分布因素；iv)对来自端血吸虫的蒽醌进行化学基因组分析，以确定其抗真菌的作用方式；v)利用其抗真菌作用方式的信息，说明端裂菌和姐妹分支之间的差异如何解释对蒽醌类的自然抗性；vi)描述Teloschistales地衣微生物组的多样性，并对其基因组进行功能性注释，以测试它们是否与其他地衣家族不同，以及它们是否具有代谢活性。”

"Lichenised fungi living in deserts and high-altitude regions face a challenge from intense UV light, which is known to cause DNA damage. Recently, we have shown that the order Teloschistales (Ascomycota), a group of >1,000 species, underwent an adaptive radiation _100 Mya, with one of the four families within this order, Teloschistaceae, experiencing an increase in diversification rates associated with a switch from bark to rock and from shady to sun-exposed habitats. Our hypothesis is that the adaptation to sunny habitats is likely to have been enabled by a contemporaneous key novel phenotypic innovation: the production of anthraquinones, secondary metabolites known to protect against UV light. Hence, two ecological factors (sun exposure and rock substrate) and the phenotypic innovation (anthraquinones) seem likely to be responsible for the success of the Teloschistaceae, one of the larges lichen-forming fungal lineages.Objectives: i) To reconstruct a genome-level phylogeny for the Teloschistales and sister clades to test whether current taxa are monophyletic and reflect evolutionary processes such as changes in branching/speciation rates; ii) Annotate secondary metabolite biosynthetic gene clusters to test whether the novel phenotypic innovation of anthraquinone biosynthesis is related to the evolution of new gene clusters; iii) Test which factors control metabolome variation in the Teloschistales e.g. phylogeny, climatic conditions (especially solar radiation levels and aridity), substrate preference and geographical distribution factors; iv) Carry out a chemogenomic assay of anthraquinones from the Teloschistales to determine their antifungal mode of action; v) Use information on their antifungal mode of action to inform how differences between Teloschistales and sister clades explain natural resistance to anthraquinones; vi) Describe the diversity of Teloschistales lichen microbiomes and functional annotate their genomes to test whether they are distinct from other lichen families and if they are metabolically active."