Biology and evolution of the ascophyllum symbiosis

这项研究计划将调查一个复杂的共生基于周围的褐藻，Ascophyllum nodosum。 本种是北大西洋冷温带的岩石潮间带海岸的主要光合生物，包括加拿大大西洋沿岸的大部分地区。 共生关系包括：i）互惠真菌（Mycophycias ascophylli），其总是存在于宿主组织中; ii）常见的红色真菌，其是Ascophyllum上的专性附生植物; iii）专性附生棕色真菌（Elachista fucicola），其通常在Ascophyllum上丰富;以及iv）迄今描述的最丰富的海洋昆虫（Halocladius variabilis），其主要限于Elachista。 该研究计划将重点关注这个共生群落的藻类和真菌成分，使用生态，生理和分子工具来了解这些物种之间相互作用的性质。 此外，从共生群落的整个分布的不同组成部分的分子进化研究将提供重要的见解冰后期北大西洋和北冰洋的海洋地理学。此外，由于Ascophyllum是加拿大东部主要收获和加工工业的基础，因此在农业应用中使用的所得产品的性质可能来自真菌共生体。 这项研究计划将有助于解决这一基本问题，通过与工业（阿斯塔纳海洋植物有限公司）合作。并让他们可以利用这些文化。总的来说，这项研究计划将提供新的见解潮间带生态学，并使Ascophyllum海洋共生的主要模式系统。

This research program will investigate a complex symbiosis based around the brown seaweed, Ascophyllum nodosum. This species is the dominant photosynthetic organism of rocky intertidal shores of the cold-temperate North Atlantic Ocean, including large parts of coastal Atlantic Canada. The symbiosis includes: i) a mutualistic fungus (Mycophycias ascophylli), which is always present in the host tissues; ii) a common red alga that is an obligate epiphyte on Ascophyllum; iii) an obligate epiphytic brown alga (Elachista fucicola) that is often abundant on Ascophyllum; and iv) the most abundant marine insect yet described (Halocladius variabilis), that is largely restricted to Elachista. The research program will focus on the algal and fungal components of this symbiotic community using ecological, physiological and molecular tools to understand the nature of the interactions among these species. In addition, the molecular-evolutionary studies of the different components of the symbiotic community from throughout its distribution will provide important insights into the post-glacial biogeography of the North Atlantic and Arctic Oceans. Furthermore, since Ascophyllum is the basis of a major harvesting and processing industry in eastern Canada, it is possible that properties of the resulting products used in agricultural applications are derived from the fungal symbiont. This research program will help address this fundamental issue by collaborating with industry (Acadian Seaplants Ltd.) and making cultures available to them. Overall, this research program will provide new insights into intertidal ecology, and make Ascophyllum a major model system for marine symbioses.