Pagenkopp Lohan Katrina M, Fleischer Robert C, Torchin Mark E, Ruiz Gregory M
Marine Invasions Research Laboratory, Smithsonian Environmental Research Center, Edgewater, MD 21037, USA; Center for Conservation Genomics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA.
Center for Conservation Genomics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA.
Protist. 2017 Apr;168(2):183-196. doi: 10.1016/j.protis.2016.12.003. Epub 2017 Jan 6.
Deciphering patterns of protistan taxa is a crucial step for understanding anthropogenic and environmental impacts on biogeography. We characterized and compared protistan communities from environmental samples collected along a major shipping corridor, the Panama Canal, and the Bocas del Toro archipelago. We used metabarcoding with high throughput sequencing (HTS) with the V4 hypervariable region of the ribosomal gene complex (rDNA). We detected many protistan taxa, including a variety of parasitic and toxic taxa. There were 1,296 OTUs shared across all three regions, with an additional 342-1,526 OTUs occurring across two or more regions, suggesting some mixing within the Caribbean and across the Isthmus. In general, this mixing did not impact community similarity, which was primarily distinct across regions. When OTUs identified as gregarines were analyzed separately, most samples grouped by region and communities were distinct across the Canal. Shipping traffic through the Panama Canal could move some taxa across regions; however, different environmental conditions in the two oceans may limit their establishment. Overall our results suggest that contemporary protistan biogeographic patterns are likely caused by a complex combination of factors, including anthropogenic dispersal and environmental tolerance.
解读原生生物分类群的模式是理解人为和环境对生物地理学影响的关键一步。我们对沿主要航运通道巴拿马运河和博卡斯德尔托罗群岛采集的环境样本中的原生生物群落进行了特征描述和比较。我们使用核糖体基因复合体（rDNA）的V4高变区进行高通量测序（HTS）的宏条形码分析。我们检测到许多原生生物分类群，包括各种寄生和有毒分类群。所有三个区域共有1296个操作分类单元（OTU），另外还有342 - 1526个OTU出现在两个或更多区域，这表明加勒比地区内部以及地峡两侧存在一些混合现象。总体而言，这种混合并未影响群落相似性，群落相似性主要在不同区域间存在差异。当单独分析被鉴定为簇虫的OTU时，大多数样本按区域分组，且运河两岸的群落各不相同。通过巴拿马运河的航运交通可能会使一些分类群跨区域移动；然而，两大洋不同的环境条件可能会限制它们的定殖。总体而言，我们的结果表明，当代原生生物生物地理模式可能是由包括人为扩散和环境耐受性在内的多种因素复杂组合导致的。
