Graf Louis, Kim Yae Jin, Cho Ga Youn, Miller Kathy Ann, Yoon Hwan Su
Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea.
National Institute of Biological Resources, Incheon, Korea.
PLoS One. 2017 Nov 2;12(11):e0187104. doi: 10.1371/journal.pone.0187104. eCollection 2017.
Coccophora langsdorfii (Turner) Greville (Fucales) is an intertidal brown alga that is endemic to Northeast Asia and increasingly endangered by habitat loss and climate change. We sequenced the complete circular plastid and mitochondrial genomes of C. langsdorfii. The circular plastid genome is 124,450 bp and contains 139 protein-coding, 28 tRNA and 6 rRNA genes. The circular mitochondrial genome is 35,660 bp and contains 38 protein-coding, 25 tRNA and 3 rRNA genes. The structure and gene content of the C. langsdorfii plastid genome is similar to those of other species in the Fucales. The plastid genomes of brown algae in other orders share similar gene content but exhibit large structural recombination. The large in-frame insert in the cox2 gene in the mitochondrial genome of C. langsdorfii is typical of other brown algae. We explored the effect of this insertion on the structure and function of the cox2 protein. We estimated the usefulness of 135 plastid genes and 35 mitochondrial genes for developing molecular markers. This study shows that 29 organellar genes will prove efficient for resolving brown algal phylogeny. In addition, we propose a new molecular marker suitable for the study of intraspecific genetic diversity that should be tested in a large survey of populations of C. langsdorfii.
郎氏囊孔藻（Coccophora langsdorfii (Turner) Greville）（墨角藻目）是一种潮间带褐藻，为东北亚特有物种，因栖息地丧失和气候变化而日益濒危。我们对郎氏囊孔藻的完整环状质体和线粒体基因组进行了测序。环状质体基因组为124,450碱基对，包含139个蛋白质编码基因、28个tRNA基因和6个rRNA基因。环状线粒体基因组为35,660碱基对，包含38个蛋白质编码基因、25个tRNA基因和3个rRNA基因。郎氏囊孔藻质体基因组的结构和基因内容与墨角藻目中的其他物种相似。其他目褐藻的质体基因组具有相似的基因内容，但表现出较大的结构重组。郎氏囊孔藻线粒体基因组中cox2基因的大框内插入是其他褐藻的典型特征。我们探究了这种插入对cox2蛋白结构和功能的影响。我们评估了135个质体基因和35个线粒体基因用于开发分子标记的有效性。本研究表明，29个细胞器基因将被证明对解析褐藻系统发育有效。此外，我们提出了一种适用于研究种内遗传多样性的新分子标记，应在对郎氏囊孔藻种群的大规模调查中进行测试。
