The long and short of doubling down: polyploidy, epigenetics, and the temporal dynamics of genome fractionation.
The long and short of doubling down: polyploidy, epigenetics, and the temporal dynamics of genome fractionation.
复制标题
DOI：
10.1016/j.gde.2018.01.004
复制
发表时间：
2018-04
影响因子：
4
通讯作者：
J. Wendel;D. Lisch;Guan-jing Hu;A. Mason
中科院分区：
文献类型：
--
作者：
J. Wendel;D. Lisch;Guan-jing Hu;A. Mason
我们考虑快速发展的植物进化基因组学学科，重点是多倍体基因组的进化。在许多谱系中，多倍体之后伴随着“有偏见的分离”，即祖先基因组中基因的不平等丢失。从机理上讲，偏向分离是由基因附近表观遗传格局的变化引起的，可能是由转座元件介导的。这些表观遗传变化导致复制体之间的基因表达不平等，建立了差异适应度，从而导致相对于祖先基因组的偏向基因丢失。基于这个模型，我们提出了一个统一的概念框架和一系列可检验的假设，将基因组大小、转座元件与基因的接近程度、表观遗传重编程、染色质可及性和基因表达联系起来。
We consider the rapidly advancing discipline of plant evolutionary genomics, with a focus on the evolution of polyploid genomes. In many lineages, polyploidy is followed by ‘biased fractionation’, the unequal loss of genes from ancestral progenitor genomes. Mechanistically, it has been proposed that biased fractionation results from changes in the epigenetic landscape near genes, likely mediated by transposable elements. These epigenetic changes result in unequal gene expression between duplicates, establishing differential fitness that leads to biased gene loss with respect to ancestral genomes. We propose a unifying conceptual framework and a set of testable hypotheses based on this model, relating genome size, the proximity of transposable elements to genes, epigenetic reprogramming, chromatin accessibility, and gene expression.