大规模的基因组缩小早于Symbiodiniaceae dinoflagellates 的分歧
Sarah Shah1, Katherine E Dougan1, Yibi Chen1
1Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia.
The ISME journal
|April 24, 2024
概括
恐龙鞭毛动物的基因组缩小早于共生,挑战了以前的假设. 自由生活的Effrenium属保留了祖先的特征,揭示了对Symbiodiniaceae基因组进化和多样化的关键见解.
科学领域:
- 海洋生物学 海洋生物学
- 基因组学就是基因组学.
- 进化生物学是进化的生物学.
背景情况:
- 交生科 (Symbiodiniaceae) 是一种与珊瑚共存的藻类,有着多样性.
- 人们认为共生 (symbiogenesis) 在这个家族中已经进化了多次.
- 对共生对Symbiodiniaceae基因组进化的影响仍然在很大程度上未被探索.
研究的目的:
- 调查自由生活的恐龙鞭属Effrenium的基因组演变.
- 确定Effrenium是否由于缺乏共生而保留了祖先的Symbiodiniaceae特征.
- 将Effrenium基因组与共生亲属进行比较,以了解生活方式驱动的基因组变化.
主要方法:
- 三个Effrenium voratum分离物 (1.2-1.9 Gbp) 的新基因组组.
- 对Effrenium voratum的转录组数据生成.
- 与16种Symbiodiniaceae种类和其他恐龙鞭状动物进行比较基因组分析.
主要成果:
- 基因组缩小早于Symbiodiniaceae的起源,与预期相反.
- 与共生种群相比,Effrenium表现出较长的内核,广泛的mRNA编辑,较少的谱系特异性基因 (~30%),以及较低的伪基因化 (~10%).
- 这些基因组特征将自由生活的Effrenium与其共生亲属区分开来.
结论:
- 基因组缩小不仅仅是Symbiodiniaceae中的共生生活方式的结果.
- 自由生活的Effrenium血统为祖先的恐龙鞭动物基因组特征提供了一个窗口.
- 基因组减少和生活方式适应是交织在一起的Symbiodiniaceae多样化的驱动因素.
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