Diversity of marine protists: single cell genomics and imaging for Tara Oceans

最近的研究发现了海洋浮游原生生物（原生动物和其他真核微生物）具有巨大多样性的证据，与海洋细菌和古细菌的惊人多样性相匹配或超过。了解这种多样性与海洋生态系统功能之间的关系对于人类应对气候变暖和海洋酸化等全球变化的影响至关重要。该项目的两个总体目标是：1)发现和比较不同海洋梯度的海洋原生生物的多样性；2)生成优势的、未培养的原生生物分类类群的参考基因组，为广泛的科学界提供资源。这个概念验证项目将Bigelow海洋科学实验室的新单细胞基因组学中心与Tara海洋探险队联合起来，探索重要海洋梯度上的原生生物多样性。塔拉海洋是一个独立资助的为期三年的环球考察项目，目的是描述海洋浮游生物的多样性（ocean.taraexpeditions.org）。这艘名为塔拉的帆船是一艘110英尺长的现代帆船，配有干湿实验室和全套海洋仪器。探险队正在为基因组测序的高通量管道以及原生生物形态学的数字成像收集样本。单个原体细胞将从塔拉收集的样本中进行分类。测序后的单个原生细胞基因组将被扩增，这些单扩增基因组（SAGs）将使用DNA条形码进行系统发育筛选，以确定最丰富和最多样化的类群，以进一步进行基因组鉴定。法国国家测序中心Genoscope已同意对数百个sag进行测序（该项目无需任何费用），以形成后续社区水平分子分析的参考基因组（平行样本也将由Tara Oceans的其他合作伙伴使用最先进的方法（如宏基因组学、元转录组学和pyrotagging）进行测序）。该项目的更广泛影响包括培养本科生和博士后，并参与Bigelow实验室和Tara海洋平台的各种既定教育和推广计划。此外，该项目还将建立一个大型海洋原生生物sag库，存档并与其他有兴趣筛选特定基因或在未来进行全基因组测序的研究人员共享。

Recent studies have uncovered evidence for a huge store of diversity in marine planktonic protists (protozoa and other eukaryotic microorganisms), matching or exceeding the incredible diversity observed for marine bacteria and archaea. Understanding relationships between this diversity and ocean ecosystem function is critical as humans navigate the effects of global change such as climate warming and ocean acidification. The two overall goals of this project are: 1) to discover and compare the diversity of marine protists across ocean gradients, and 2) to generate reference genomes of dominant, uncultured protist taxonomic groups, to serve as a resource for a broad scientific community.This proof-of-concept project teams Bigelow Laboratory for Ocean Sciences' new Single Cell Genomics Center with the Tara Oceans Expedition to explore protistan diversity across important oceanographic gradients. Tara Oceans is an independently-funded, three-year, circum-global expedition to describe the diversity of marine plankton (oceans.taraexpeditions.org). The boat, Tara, is a modern 110-ft sailing schooner with wet and dry laboratories and a complete suite of oceanographic instruments. The expedition is collecting samples for high-throughput pipelines for genome sequencing as well as digital imaging protist morphology. Single protistan cells will be sorted from samples collected on Tara. The genomes of sorted single protist cells will be amplified, and these single amplified genomes (SAGs) will be phylogentically screened using DNA bar codes to identify the most abundant and diversed taxa for further genomic characterization. The French national sequencing center, Genoscope, has agree to sequence hundreds of SAGs (at no cost to this project) to form reference genomes for subsequent community-level molecular analyses (parallel samples will also be sequenced by other Tara Oceans partners using state-of the-art methods such as metagenomics, meta-transcriptomics, and pyrotagging). The broader impacts of this project include the training of undergraduate and postdoctoral students, and involvement in various established education and outreach programs at Bigelow Laboratory and via the Tara Oceans platform. In addition the project will create a large library of marine protist SAGs to be archived and shared with other researchers interested in screening them for specific genes or performing whole genome sequencing in the future.