Vanneste Kevin, Maere Steven, Van de Peer Yves
Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium Genomics Research Institute (GRI), University of Pretoria, 0028 Pretoria, South Africa
Philos Trans R Soc Lond B Biol Sci. 2014 Aug 5;369(1648). doi: 10.1098/rstb.2013.0353.
Genome sequencing has demonstrated that besides frequent small-scale duplications, large-scale duplication events such as whole genome duplications (WGDs) are found on many branches of the evolutionary tree of life. Especially in the plant lineage, there is evidence for recurrent WGDs, and the ancestor of all angiosperms was in fact most likely a polyploid species. The number of WGDs found in sequenced plant genomes allows us to investigate questions about the roles of WGDs that were hitherto impossible to address. An intriguing observation is that many plant WGDs seem associated with periods of increased environmental stress and/or fluctuations, a trend that is evident for both present-day polyploids and palaeopolyploids formed around the Cretaceous-Palaeogene (K-Pg) extinction at 66 Ma. Here, we revisit the WGDs in plants that mark the K-Pg boundary, and discuss some specific examples of biological innovations and/or diversifications that may be linked to these WGDs. We review evidence for the processes that could have contributed to increased polyploid establishment at the K-Pg boundary, and discuss the implications on subsequent plant evolution in the Cenozoic.
基因组测序表明，除了频繁的小规模重复外，在生命进化树的许多分支上都发现了大规模重复事件，如全基因组重复（WGD）。特别是在植物谱系中，有证据表明存在反复发生的WGD，事实上，所有被子植物的祖先很可能是一个多倍体物种。在已测序的植物基因组中发现的WGD数量，使我们能够研究一些关于WGD作用的问题，而这些问题以前是无法解决的。一个有趣的观察结果是，许多植物WGD似乎与环境压力增加和/或波动的时期有关，这一趋势在现今的多倍体和大约6600万年前白垩纪-古近纪（K-Pg）灭绝事件前后形成的古多倍体中都很明显。在这里，我们重新审视标志着K-Pg边界的植物中的WGD，并讨论一些可能与这些WGD相关的生物创新和/或多样化的具体例子。我们回顾了可能导致K-Pg边界多倍体建立增加的过程的证据，并讨论了其对新生代后续植物进化的影响。
