What's in a genome? The C-value enigma and the evolution of eukaryotic genome content
What's in a genome? The C-value enigma and the evolution of eukaryotic genome content
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DOI：
10.1098/rstb.2014.0331
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发表时间：
2015-09-26
影响因子：
6.3
通讯作者：
Gregory, T. Ryan
中科院分区：
文献类型：
--
作者：
Elliott, Tyler A.;Gregory, T. Ryan
除了一些值得注意的例外，真核基因组在许多方面与细菌和古生物的基因组不同，包括染色体结构和数量、重复DNA含量以及蛋白质编码区内含子的存在。真核生物和原核生物基因组之间最显著的区别之一是大小。与原核生物不同，真核生物在基因组大小上表现出巨大的(超过6万倍)的变异性，这并不是用基因数量的差异来解释的。众所周知，基因组大小与细胞大小和分裂速度相关，进而与新陈代谢、发育速度或身体大小等许多生物体水平的特征相关。基因组大小和基因组的其他性质之间的关系，如基因含量、转座元件含量、碱基对组成和相关特征，描述得较少。“完整的”基因组测序项目的迅速扩展，首次使人们有可能在广泛的真核生物中研究这些关系，以便对基因组大小多样性的原因和相互关系有新的了解。这项研究展示了500多种真核生物基因组数据的系统发育比较结果。描述了基因组大小和其他基因组参数之间的几个关系，并就如何在未来更广泛地扩展这些见解提出了一些建议。
Some notable exceptions aside, eukaryotic genomes are distinguished from those of Bacteria and Archaea in a number of ways, including chromosome structure and number, repetitive DNA content, and the presence of introns in protein-coding regions. One of the most notable differences between eukaryotic and prokaryotic genomes is in size. Unlike their prokaryotic counterparts, eukaryotes exhibit enormous (more than 60 000-fold) variability in genome size which is not explained by differences in gene number. Genome size is known to correlate with cell size and division rate, and by extension with numerous organism-level traits such as metabolism, developmental rate or body size. Less well described are the relationships between genome size and other properties of the genome, such as gene content, transposable element content, base pair composition and related features. The rapid expansion of 'complete' genome sequencing projects has, for the first time, made it possible to examine these relationships across a wide range of eukaryotes in order to shed new light on the causes and correlates of genome size diversity. This study presents the results of phylogenetically informed comparisons of genome data for more than 500 species of eukaryotes. Several relationships are described between genome size and other genomic parameters, and some recommendations are presented for how these insights can be extended even more broadly in the future.