Mao Yafei, Satoh Noriyuki
Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan.
Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan.
iScience. 2019 Mar 29;13:20-32. doi: 10.1016/j.isci.2019.02.001. Epub 2019 Feb 6.
Whole-genome duplication (WGD) has been recognized as a significant evolutionary force in the origin and diversification of multiple organisms. Acropora, a speciose reef-building coral genus, is suspected to have originated by polyploidy. Yet, there is no genetic evidence to support this hypothesis. Using comprehensive phylogenomic and comparative genomic approaches, we analyzed six Acroporid genomes and found that a WGD event likely occurred ∼31 million years ago in the most recent common ancestor of Acropora, concurrent with a worldwide coral extinction. We found that duplicated genes were highly enriched in gene regulation functions, including those of stress responses. The functional clusters of duplicated genes are related to the divergence of gene expression patterns during development. Some proteinaceous toxins were generated by WGD in Acropora compared with other cnidarian species. Collectively, this study provides evidence for an ancient WGD event in corals, which helps explain the origin and diversification of Acropora.
全基因组复制（WGD）已被公认为是多种生物起源和多样化过程中的一种重要进化力量。鹿角珊瑚属（Acropora）是一个种类繁多的造礁珊瑚属，人们怀疑它起源于多倍体。然而，目前尚无遗传证据支持这一假说。我们运用全面的系统发育基因组学和比较基因组学方法，分析了六个鹿角珊瑚科（Acroporid）基因组，发现全基因组复制事件可能在约3100万年前发生在鹿角珊瑚属的最近共同祖先中，这与一次全球性的珊瑚灭绝事件同时发生。我们发现，重复基因在基因调控功能中高度富集，包括应激反应相关的功能。重复基因的功能簇与发育过程中基因表达模式的差异有关。与其他刺胞动物物种相比，鹿角珊瑚属中的全基因组复制产生了一些蛋白质毒素。总的来说，这项研究为珊瑚中古老的全基因组复制事件提供了证据，这有助于解释鹿角珊瑚属的起源和多样化。
