Transposable elements and the evolution of genome size in eukaryotes
Transposable elements and the evolution of genome size in eukaryotes
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DOI：
10.1023/a:1016072014259
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发表时间：
2002-05-01
期刊：
影响因子：
1.5
通讯作者：
Kidwell, MG
中科院分区：
文献类型：
--
作者：
Kidwell, MG
人们普遍认为，在真核生物物种中观察到的基因组大小的广泛差异与重复DNA的数量的关系比与编码基因的数量的关系更密切。重复DNA的主要类型包括转座元件、卫星DNA、简单序列和串联重复序列，但很难获得这些不同类型对总基因组大小的相对贡献的可靠估计。随着基因组测序的出现，这类信息开始变得可用，但目前还不能从有限的数据中得出确切的结论。在这里，其中转座因子贡献直接和间接基因组大小变化的方式进行了探讨。有限的证据支持总转座元件DNA和基因组大小之间存在近似线性关系。在小基因组中，每个家族的拷贝数很低，而且在全球范围内受到限制，但在大基因组中差异很大。因此，转座元件拷贝数限制的部分释放似乎是大型基因组的主要特征。
It is generally accepted that the wide variation in genome size observed among eukaryotic species is more closely correlated with the amount of repetitive DNA than with the number of coding genes. Major types of repetitive DNA include transposable elements, satellite DNAs, simple sequences and tandem repeats, but reliable estimates of the relative contributions of these various types to total genome size have been hard to obtain. With the advent of genome sequencing, such information is starting to become available, but no firm conclusions can yet be made from the limited data currently available. Here, the ways in which transposable elements contribute both directly and indirectly to genome size variation are explored. Limited evidence is provided to support the existence of an approximately linear relationship between total transposable element DNA and genome size. Copy numbers per family are low and globally constrained in small genomes, but vary widely in large genomes. Thus, the partial release of transposable element copy number constraints appears to be a major characteristic of large genomes.