Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D 06466 Gatersleben, Stadt Seeland, Germany.
Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D 06466 Gatersleben, Stadt Seeland, Germany.
Trends Plant Sci. 2016 Sep;21(9):749-757. doi: 10.1016/j.tplants.2016.06.003. Epub 2016 Jul 14.
The reason why the DNA content, chromosome number and shape, and gene content of eukaryotic genomes vary independently remains a matter of speculation. The same is true for the questions of whether there is a general tendency for increase or decrease of genome size and chromosome number and whether genome size and/or chromosome number have an adaptive value and, if so, what this value is. Here we assume that three strategies of genome evolution (shrinkage, expansion, and equilibrium) have developed to find the optimal balance between genomic stability and plasticity. We suggest various modes of DNA double-strand break (DSB) repair in combination with whole-genome duplication (WGD) and dysploid chromosome number alteration to explain the different strategies of genome size and karyotype evolution.
真核基因组的 DNA 含量、染色体数目和形状以及基因含量独立变化的原因仍然是推测的。基因组大小和染色体数目增加或减少的一般趋势是否存在，以及基因组大小和/或染色体数目是否具有适应性价值，如果有，其价值是什么，这些问题也是如此。在这里，我们假设已经开发出三种基因组进化策略（收缩、扩张和平衡），以在基因组稳定性和可塑性之间找到最佳平衡。我们提出了各种 DNA 双链断裂 (DSB) 修复模式，结合全基因组复制 (WGD) 和非整倍体染色体数目的改变，来解释基因组大小和核型进化的不同策略。
