Linking microscopy-based identities to molecular identities for problem- or problematic protozoa.

地球上大多数复杂生命的主要群体不是动物、真菌、植物或藻类，而是各种自由生活的原生动物。这些单细胞捕食者在生态学上很重要，因为它们通常是细菌和单细胞藻类（构成海洋生态系统的基础）最重要的消费者。有些还能引起动物疾病（见下文）。该申请将支持三个不同的项目，涉及被忽视的原生动物的生物多样性、分布和/或进化。这些项目都涉及到将DNA数据与基于显微镜的鉴定联系起来。* *项目1：掠食性真glenids是沉积物中重要的原生动物，具有进化意义，但由于培养物很少，因此很难研究。例如，这里的DNA数据来自于比海水多5倍的盐)，其中包含了许多这种环境所特有的原生动物。然而，几乎所有这类研究使用的材料都来自人工或寿命较短的栖息地（例如太阳盐沼或小水池）。我们将调查大型永久大盐湖的原生动物，检查水和浅层沉积物样本。这项调查将使用光学显微镜，单细胞分离和培养，以及环境基因序列调查。这将测试从人工/短暂系统中培养的生物是否能很好地代表一般高盐系统中可培养和不可培养的多样性。我们还将能够与地中海海底奇怪的“深高盐缺氧盆地”推断的物种清单进行比较，以确定它们实际上有多不寻常。* *项目3：海带林是非常多产的栖息地，是鱼类的重要苗圃。海胆的放牧使新斯科舍省大西洋沿岸的大片海带森林变成了名副其实的“荒地”。海胆的数量水平是由一种致病的原生动物控制的，这是一种兼性寄生虫（即它也可以在宿主外生活和生长）。这种疾病非常依赖温度，在夏末发作，但人们不知道这种原生动物来自哪里，尤其是它是如何过冬的。我们将开发敏感的基于dna的方法来检测Paramoeba，并使用这些方法尝试在不同的环境水柱和沉积物样本中检测它。我们还将探索在不同地点发现的原生动物是否有不同的遗传菌株，或者对海胆的杀伤力是否不同。在气候变化的情况下，需要这些数据来准确预测其未来的范围和对大西洋地区海带森林的影响（以及它们提供的生态系统服务）。

Most of the major groups of complex life on Earth are not animals, fungi, plants or algae, but are instead varieties of free-living protozoa. These single celled predators are ecologically important because are often the most important consumers of bacteria and single-celled algae (which form the base of the ocean ecosystem). Some can also cause disease in animals (see below). This application is to support three distinct projects on the biodiversity, distribution and/or evolution of neglected protozoa. The projects all involve connecting DNA data to microscopy-based identification.* *Project 1: Predatory (phagotrophic) euglenids are important protozoa in sediments, and are of evolutionary interest, but have been difficult to study because there are very few cultures. For example, there are DNA data from 5 times more salt than seawater) harbor many protozoa that are unique to this environment. However, almost all such studies used material from artificial or short-lived habitats (e.g. solar salterns or tiny pools). We will survey the protozoa from the large permanent Great Salt Lake, examining water and shallow sediment samples. This survey will use light microscopy, single cell isolations, and culturing, along with an environmental gene-sequence survey. This will test whether the collection of organisms already cultured from artificial/ephemeral systems represents well the culturable and unculturable diversity from very salty systems in general. We will also be able to compare to species inventories inferred for the strange `deep hypersaline anoxic basins' on the Mediterranean Sea floor, to determine how unusual they actually are. * *Project 3: Kelp forests are very productive habitats that are important nurseries for fish. Grazing by sea urchins turns large areas of kelp forest on the Atlantic Coast of Nova Scotia into aptly-named `barrens' . The sea urchin population levels are controlled by a disease-causing protozoan, Paramoeba invadens, which is a facultative parasite (i.e. it can also live and grow outside the host). The disease is very temperature-dependent and strikes in late summer, but it is not known where the protozoan comes from, especially how it over-winters. We will develop sensitive DNA-based methods to detect the Paramoeba, and use these to try to detect it in different environmental water column and sediment samples over time. We will also explore whether there are different genetic strains of the protozoan, found in different locations, or that differ in lethality to sea urchins. This data is needed for making accurate predictions of its future extent and influence on kelp forests in the Atlantic region (and thus the ecosystem services they provide) under climate change.