Symbiodinium (Pyrrhophyta) genome sizes (DNA content) are smallest among dinoflagellates
Symbiodinium (Pyrrhophyta) genome sizes (DNA content) are smallest among dinoflagellates
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DOI：
10.1111/j.0022-3646.2005.04231.x
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发表时间：
2005-08-01
影响因子：
2.9
通讯作者：
Galbraith, DW
中科院分区：
文献类型：
--
作者：
LaJeunesse, TC;Lambert, G;Galbraith, DW
使用流式细胞术分析的荧光，我们测量了18个培养的“自由生活”的物种和29个共生藻属的基因组大小。从石珊瑚、柳珊瑚、海葵、水母和巨蛤中培养的分离物。基因组大小与细胞大小直接相关，如先前对于大多数真核细胞系所记载的。在最小的甲藻中，共生甲藻属（Symbiodinium spp.）(6-15μ m）具有我们测量的最低DNA含量（1.5-4.8 pg.cell（-1））。在Alexandrum，Karenia，Pfiesteria和Prorocentrum属中的开花或潜在有害物种的基因组大小约为2至50倍。系统发育分析表明，在甲藻的进化过程中，基因组/细胞大小明显增加和减少反复。相比之下，亲缘关系较远和亲缘关系较近的共生藻属物种的基因组大小相对一致。这可能是产品的细胞内宿主栖息地施加强大的选择压力，限制了共生体的大小。
Using flow cytometric analysis of fluorescence, we measured the genome sizes of 18 cultured "free-living" species and 29 Symbiodinium spp. isolates cultured from stony corals, gorgonians, anemones, jellyfish, and giant clams. Genome size directly correlated with cell size, as documented previously for most eukaryotic cell lines. Among the smallest of dinoflagellates, Symbiodinium spp. (6-15 mu m) possessed the lowest DNA content that we measured (1.5-4.8 pg.cell(-1)). Bloom-forming or potentially harmful species in the genera Alexandrium, Karenia, Pfiesteria, and Prorocentrum possessed genomes approximately 2 to 50 times larger in size. A phylogenetic analysis indicated that genome/cell size has apparently increased and decreased repeatedly during the evolution of dinoflagellates. In contrast, genome sizes were relatively consistent across distantly and closely related Symbiodinium spp. This may be the product of intracellular host habitats imposing strong selective pressures that have restricted symbiont size.