The dynamic nature of genomes across the tree of life.
The dynamic nature of genomes across the tree of life.
复制标题
生命树上基因组的动态性质。
DOI：
10.1093/gbe/evu024
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发表时间：
2014
影响因子：
3.3
通讯作者：
Katz,LauraA
中科院分区：
文献类型：
--
作者：
Oliverio,AngelaM;Katz,LauraA
基因组在生命之树的谱系中是动态的。例如，在细菌和古生菌中，DNA含量在整个生命周期中都不同，不同谱系中的非二元细胞分裂表明需要协调基因组的遗传。这些观察结果与教科书上的观点形成了鲜明对比，即细菌和古生菌的基因组是单倍体的(即，单拷贝的)，并且在物种内和整个个体的一生中都是固定的。在这里，我们从代表不同的细菌和古菌谱系的样本中合成关于动态基因组的三个方面的信息：1)倍性水平变化，2)表观遗传机制，3)生命周期变化。例如，迄今分析的Eurya chaeota都是多倍体，EPulopiscium细菌也是如此，它包含多达数万个基因组副本，并通过胎生繁殖。耐辐射葡萄球菌和古盐生细菌。NRC-1可以在几小时内修复高度碎片化的基因组。此外，皮肤病和植物霉菌等细菌属分别通过分裂(即从一个细胞产生多个细胞)和发芽繁殖，突出了对这些谱系中基因组遗传进行调节的必要性。结合这些数据和我们之前在真核生物中广泛存在的基因组动力学的工作，我们假设动态基因组是生命之树上的一条规则，而不是例外。此外，我们推测，所有的结构域都可能具有区分胚系和体细胞DNA的能力，这种能力可能存在于最后一个普遍的共同祖先。
Genomes are dynamic in lineages across the tree of life. Among bacteria and archaea, for example, DNA content varies throughout life cycles, and nonbinary cell division in diverse lineages indicates the need for coordination of the inheritance of genomes. These observations contrast with the textbook view that bacterial and archaeal genomes are monoploid (i.e., single copied) and fixed both within species and throughout an individual’s lifetime. Here, we synthesize information on three aspects of dynamic genomes from exemplars representing a diverse array of bacterial and archaeal lineages: 1) ploidy level variation, 2) epigenetic mechanisms, and 3) life cycle variation. For example, the Euryarchaeota analyzed to date are all polyploid, as is the bacteriumEpulopisciumthat contains up to tens of thousands of copies of its genome and reproduces by viviparity. The bacteriumDeinococcus radioduransand the archaeonHalobacteriumsp. NRC-1 can repair a highly fragmented genome within a few hours. Moreover, bacterial genera such asDermocarpellaandPlanctomycesreproduce by fission (i.e., generating many cells from one cell) and budding, respectively, highlighting the need for regulation of genome inheritance in these lineages. Combining these data with our previous work on widespread genome dynamics among eukaryotes, we hypothesize that dynamic genomes are a rule rather than the exception across the tree of life. Further, we speculate that all domains may have the ability to distinguish germline from somatic DNA and that this ability may have been present the last universal common ancestor.