Department of Biology , Arcadia University , 450 South Easton Road, Glenside, PA 19038 , USA.
AoB Plants. 2011;2011:plr001. doi: 10.1093/aobpla/plr001. Epub 2011 Jan 18.
Brown algae are critical components of marine ecosystems around the world. However, the genome of only one species of the class has so far been sequenced. This contrasts with numerous sequences available for model organisms such as higher plants, flies or worms. The present communication expands our coverage of DNA content information to 98 species of brown algae with a view to facilitating further genomic investigations of the class.
The DNA-localizing fluorochrome DAPI (4',6-diamidino-2-phenylindole) and the red blood cell (chicken erythrocyte) standard were used to estimate 2C values by static microspectrophotometry.
2C DNA contents are reported for 98 species of brown algae, almost doubling the number of estimates available for the class. The present results also expand the reported DNA content range to 0.2-3.6 pg, with several species of Fucales and Laminariales containing apparent polyploid genomes with 2C = 1.8-3.6 pg.
The data provide DNA content values for 12 of the 19 recognized orders of brown algae spanning the breadth of the class. Despite earlier contentions concerning DNA content and the presence of oogamy, the present results do not support a correlation between phylogenetic placement and genome size. The closest sister groups to the brown algae have genome sizes on the order of 0.3 pg (e.g. Schizocladiophyceae), suggesting that this may be the ancestral genome size. However, DNA content ranges widely across the class.
褐藻是全球海洋生态系统的重要组成部分。然而，迄今为止，仅对该纲的一个物种进行了基因组测序。这与高等植物、苍蝇或蠕虫等模式生物的大量序列形成了鲜明对比。本研究通过静态显微分光光度法，使用 DNA 定位荧光染料 DAPI（4'，6-二脒基-2-苯基吲哚）和鸡红细胞标准品，将 DNA 含量信息的覆盖范围扩大到 98 种褐藻，以期促进该纲的进一步基因组研究。
使用 DNA 定位荧光染料 DAPI（4'，6-二脒基-2-苯基吲哚）和鸡红细胞标准品，通过静态显微分光光度法来估计 2C 值。
报告了 98 种褐藻的 2C DNA 含量，几乎是该纲现有估计值的两倍。本研究结果还将报道的 DNA 含量范围扩展到 0.2-3.6pg，其中几个 Fucales 和 Laminariales 物种含有明显的多倍体基因组，2C=1.8-3.6pg。
这些数据为褐藻纲 19 个公认目中的 12 个提供了 DNA 含量值，涵盖了该纲的广泛范围。尽管先前有关于 DNA 含量和卵式生殖存在的论点，但本研究结果不支持系统发育位置与基因组大小之间的相关性。褐藻最接近的姐妹群的基因组大小约为 0.3pg（例如，Schizocladiophyceae），这表明这可能是原始的基因组大小。然而，该纲的 DNA 含量范围很广。
