Collaborative Research: ATOL: A Phylogenetic and Genomic Investigation of the Algal Heterokont Tree

Robert A. Andersen （Bigelow海洋科学实验室，缅因州西布斯湾港），Rose Ann Cattolico和Gabrielle Rocap（华盛顿大学，华盛顿州西雅图），Robert Jansen， Elizabeth Ruck和Edward Theriot（德克萨斯大学，德克萨斯州奥斯汀），Matt Julius（圣克劳德州立大学，明尼苏达州圣克劳德），Stefano Draisma（国家植物标本馆和莱顿大学，荷兰莱顿）和Hiroshi Kawai（神户大学，神户）。（日本）通过生成两个大型分子数据集来确定异源类之间的关系。目前，异源藻类已被确定为14个分类类，所描述的种类超过10万种（据专家估计，总种类多达100万种）。常见的成员包括褐海藻（如海带）和硅藻。值得注意的是，尽管进行了两个世纪的光学显微镜研究，50年的电子显微镜研究和20年的分子研究，14个类之间的系统发育关系仍然未知。将获得270种异源藻和30种非藻近缘种的7个核、线粒体和叶绿体基因的DNA序列，并对30种异源藻的整个叶绿体基因组进行测序。基因组序列将为了解叶绿体及其起源提供重要的新数据，特别是因为这一领域的知识在很大程度上偏向于陆地植物。藻类是海洋中所有生物食物链的基础，大约占全球光合作用的一半，因此它们提供了我们呼吸的大约50%的氧气。异源藻的成员形态各异，从简单的单细胞到高度复杂的海藻。褐藻是海藻床的主要成分，作为食物资源和生物质资源具有很高的经济价值。许多异源藻对海洋生物有害。例如，一些藻类产生毒素，当集中在贝类中时，会杀死人类，而其他种类的异源藻是众所周知的鱼类杀手。相反，其他异交化合物作为人类的食物来源，它们被用于工业过程，它们在纳米技术工业中得到了新的认可。与异源共生藻类最近的亲戚是假真菌，其中包括许多植物病原体，例如导致爱尔兰马铃薯饥荒的真菌，以及各种霉菌和霉菌。来自不同文化和种族背景的研究生、本科生和博士后将在广泛的领域得到支持和培训，包括进化、基因组学、分子生物学、计算生物学和植物生物学。这项研究将与K-12教育工作者、公共博物馆和公园结合起来，利用几个参与机构已经建立的项目。Deep Brown网站已经建立，作为这个项目的一部分，它将得到极大的扩展。

An award has been made to Robert A. Andersen (Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, Maine), Rose Ann Cattolico and Gabrielle Rocap (University of Washington, Seattle, Washington), Robert Jansen, Elizabeth Ruck and Edward Theriot (University of Texas, Austin Texas), Matt Julius (St. Cloud State University, St. Cloud, Minnesota), Stefano Draisma (National Herbarium and Leiden University, Leiden, The Netherlands) and Hiroshi Kawai (Kobe University, Kobe, Japan) to determine the relationships among the heterokont classes by generating two large molecular data sets. Currently, 14 taxonomic classes of heterokont algae are recognized, and they include over 100,000 described species (as many as one million total species has been estimated by experts). Common members include brown seaweeds (e.g., kelp) and the diatoms. Remarkably, despite two centuries of light microscopic study, 50 years of electron microscopic study, and 20 years of molecular investigations, the phylogenetic relationships among the 14 classes remains unknown. DNA sequences of seven nuclear, mitochondrial, and chloroplast genes from 270 heterokont algal species and 30 nonalgal relatives will be obtained and, entire chloroplast genomes from 30 species will be sequenced. The genome sequences will provide important new data for understanding chloroplasts and their origin(s), especially since knowledge in this field is greatly biased toward land plants. Algae serve as the base of the food chain for all organisms that dwell in the ocean and account for approximately half of the global photosynthesis, and therefore they provide approximately 50% of the oxygen we breathe. Members of the heterokont algae vary in morphology from simple unicells to highly complex seaweeds. Brown algae are the principal elements of seaweed beds and these macroalgae have high economic values as food and biomass resources. A number of heterokont algae are harmful to marine life. For example, some algae produce toxins that when concentrated in shellfish kill humans, while other species of heterokonts are well-known fish killers. Conversely, other heterokonts serve as a human food source, they are used in industrial processes and they have found new recognition in the nanotechnology industry. The closest relatives to the heterokont algae are the pseudofungi, which include many plant pathogens, such as the fungus that caused the Irish potato famine, and various molds and mildews. Graduate and undergraduate students and postdoctoral fellows from diverse cultural and ethnic backgrounds will be supported and trained in a wide diversity of fields, including evolution, genomics, molecular biology, computational biology, and plant biology. The research will be integrated with K-12 educators, public museums and parks using already established programs at several of the participating institutions. A Deep Brown web site already has been established, and it will be greatly expanded as part of this project.