Evolution of lichen-forming fungi, algae, and secondary metabolites

覆盖北方生态系统的大片地衣形成了藻类和真菌（共生体）之间相互作用（共生体）的马赛克。这些地衣的广泛成功可能归因于藻类共生体和真菌次级代谢产物（聚酮化合物）。光合作用产生的藻类碳水化合物被转移到真菌伴侣中并用于聚酮化合物的合成。聚酮化合物具有生态效益，如光屏蔽和抗菌活性，有助于地衣在其栖息地生存，但它们也可能在生物技术中应用。这项研究计划的长期目标是了解地衣共生体及其聚酮化合物在地衣占主导地位的栖息地的功能生态学和进化。 我将调查的生态模式，在藻类共生体和真菌聚酮化合物的生产在4个石蕊物种分布在大陆和沿海栖息地。这些物种的不同化学型将测试2个硕士项目的假设，即藻类共生体和气候影响聚酮化合物的生产。由于地衣共生体的重要性，有助于保护地衣免受不利条件的聚酮化合物应在共生体相互作用的早期阶段产生。因此，我的第二个目标是博士和2个理学士项目是比较转录活性PKS基因在2个培养处理;真菌单独生长和真菌和真菌相互作用在一起。这项研究将揭示在存在和不存在的PKS基因的活性。由于生长条件已被假设影响聚酮化合物的生产，博士，3理学士和PDF项目的第三个目标是比较C。在不同条件下生长的rangiferina，以确定差异转录的PKS基因，提供深入了解基因功能，导致进一步的生物技术研究。 我的研究计划提供了一个更好的理解地衣共生在地衣为主的栖息地的进化和适应策略，但这项拟议中的研究将解决的作用，在聚酮合成，建立PKS基因转录的早期阶段的相互作用，并检查生态效益和分离的PKS基因的生物技术。10个HQP被整合在拟议的研究中，用于解决当今问题的前沿技术培训-发现新的生物活性分子和环境变化对维持北极生物多样性的影响。

Large expanses of lichens that cover northern ecosystems form a mosaic of interactions (symbioses) between algae and fungi (symbionts). The widespread success of these lichens may be attributed to the algal symbiont and fungal secondary metabolites (polyketides). Algal carbohydrates from photosynthesis are transferred to the fungal partner and used in polyketide synthesis. Polyketides have ecological benefits such as light screening and antimicrobial activity that help the lichen survive in its habitat, but they may also have applications in biotechnology. The long-term goal of this research program is to understand the functional ecology and evolution of lichen symbionts and their polyketides in lichen dominated habitats. I will investigate ecological patterns in the algal symbiont and fungal polyketide production in 4 Cladonia species distributed among continental and coastal habitats. The varied chemotypes of these species will test hypotheses for 2 MSc projects that the algal symbiont and climate influence polyketide production. Since the alga is essential for the lichen symbiosis, polyketides that help protect the alga from adverse conditions should be produced in early stages of the symbiont interaction. Therefore, my second objective for a PhD and 2 BSc projects is to compare transcriptionally active PKS genes in 2 culture treatments; the fungus growing alone and the fungus and alga interacting together. This study will reveal active PKS genes in the presence and absence of the alga. Since growing conditions have been hypothesized to affect polyketide production, the third objective for a PhD, 3 BSc, and PDF projects is to compare transcriptomes from C. rangiferina grown under different conditions to identify the differentially transcribed PKS genes providing insights into gene function leading to further biotechnology studies. My research program has provided a better understanding of the evolutionary and adaptive strategies of lichen symbioses in lichen-dominated habitats but this proposed research will address the role of the alga in polyketide synthesis, establish PKS gene transcription at early stages in the interaction, and examine ecological benefits and isolation of PKS genes for biotechnology. Ten HQP are integrated within the proposed research for training in leading edge technology on topics addressing current day issues - discovery of new bioactive molecules and impact of environmental change on the maintenance of arctic biodiversity.