The Chloroplast Genome of a Symbiodinium sp Clade C3 Isolate
The Chloroplast Genome of a Symbiodinium sp Clade C3 Isolate
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DOI：
10.1016/j.protis.2013.09.006
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发表时间：
2014-01-01
期刊：
影响因子：
2.5
通讯作者：
Howe, Christopher J.
中科院分区：
文献类型：
--
作者：
Barbrook, Adrian C.;Voolstra, Christian R.;Howe, Christopher J.
共生藻属的甲藻在珊瑚和其他底栖海洋动物中形成了重要的共生环境。与在植物和其他藻类中检测到的相比，甲藻的叶绿体基因组极少。在甲藻中，叶绿体基因位于小的质粒上，通常被称为“微环”。然而，甲藻的叶绿体基因组只有少数几个物种的广泛特征。也有证据表明，在这些被检查的物种中，叶绿体基因组组织存在相当大的差异。因此，我们对一种环境珊瑚分离物的叶绿体基因组进行了表征，在这种情况下，含有一种属于共生菌的共生体。Clade C3。基因组的基因内容与以前描述的基因组相比保存得很好。然而，与之前描述的甲藻类叶绿体基因组不同，我们没有发现任何“空的”微环。与其他藻类相比，该叶绿体基因组的序列显示出较高的进化速度。尤其值得注意的是，光系统I的核心多肽中有令人惊讶的高水平序列差异，其原因目前尚不清楚。该叶绿体基因组还具有独特的密码子使用和GC含量。这些特征表明，共生线虫的叶绿体基因组是高度可塑性的。(C)2013年禤浩焯·C·巴布鲁克。由Elsevier GmbH出版。版权所有。
Dinoflagellate algae of the genus Symbiodinium form important symbioses within corals and other benthic marine animals. Dinoflagellates possess an extremely reduced plastid genome relative to those examined in plants and other algae. In dinoflagellates the plastid genes are located on small plasmids, commonly referred to as 'minicircles'. However, the chloroplast genomes of dinoflagellates have only been extensively characterised from a handful of species. There is also evidence of considerable variation in the chloroplast genome organisation across those species that have been examined. We therefore characterised the chloroplast genome from an environmental coral isolate, in this case containing a symbiont belonging to the Symbiodinium sp. clade C3. The gene content of the genome is well conserved with respect to previously characterised genomes. However, unlike previously characterised dinoflagellate chloroplast genomes we did not identify any ` empty' minicircles. The sequences of this chloroplast genome show a high rate of evolution relative to other algal species. Particularly notable was a surprisingly high level of sequence divergence within the core polypeptides of photosystem I, the reasons for which are currently unknown. This chloroplast genome also possesses distinctive codon usage and GC content. These features suggest that chloroplast genomes in Symbiodinium are highly plastic. (C) 2013 Adrian C. Barbrook. Published by Elsevier GmbH. All rights reserved.