Tayalé A, Parisod C
Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.
Cytogenet Genome Res. 2013;140(2-4):79-96. doi: 10.1159/000351318. Epub 2013 Jun 8.
The last decade highlighted polyploidy as a rampant evolutionary process that triggers drastic genome reorganization, but much remains to be understood about their causes and consequences in both autopolyploids and allopolyploids. Here, we provide an overview of the current knowledge on the pathways leading to different types of polyploids and patterns of polyploidy-induced genome restructuring and functional changes in plants. Available evidence leads to a tentative 'diverge, merge and diverge' model supporting polyploid speciation and stressing patterns of divergence between diploid progenitors as a suitable predictor of polyploid genome reorganization. The merging of genomes at the origin of a polyploid lineage may indeed reveal different kinds of incompatibilities (chromosomal, genic and transposable elements) that have accumulated in diverging progenitors and reduce the fitness of nascent polyploids. Accordingly, successful polyploids have to overcome these incompatibilities through non-Mendelian mechanisms, fostering polyploid genome reorganization in association with the establishment of new lineages. See also sister article focusing on animals by Collares-Pereira et al., in this themed issue.
过去十年凸显了多倍体作为一种普遍存在的进化过程，它引发了剧烈的基因组重组，但对于其在同源多倍体和异源多倍体中的成因及后果，仍有许多有待了解。在此，我们概述了当前关于导致不同类型多倍体的途径以及多倍体诱导的植物基因组重组和功能变化模式的知识。现有证据引出了一个初步的“分化、融合再分化”模型，该模型支持多倍体物种形成，并强调二倍体祖先之间的分化模式是多倍体基因组重组的合适预测指标。在多倍体系谱起源时基因组的融合确实可能揭示出在分化的祖先中积累的不同类型的不相容性（染色体、基因和转座元件），并降低新生多倍体的适应性。因此，成功的多倍体必须通过非孟德尔机制克服这些不相容性，在建立新谱系的过程中促进多倍体基因组重组。另见本期主题中Collares-Pereira等人关注动物的姊妹文章。
