**http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html
Whole-genome duplication (WGD), or polyploidy, followed by gene loss and
diploidization has long been recognized as an important evolutionary
force in animals, fungi and other organisms^1
<http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html#ref1>,
2
<http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html#ref2>,
3
<http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html#ref3>
, especially plants. The success of angiosperms has been attributed, in
part, to innovations associated with gene or whole-genome duplications^4
<http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html#ref4>,
5
<http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html#ref5>,
6
<http://www.nature.com/nature/journal/v473/n7345/full/nature09916.html#ref6>
, but evidence for proposed ancient genome duplications pre-dating the
divergence of monocots and eudicots remains equivocal in analyses of
conserved gene order. Here we use comprehensive phylogenomic analyses of
sequenced plant genomes and more than 12.6 million new
expressed-sequence-tag sequences from phylogenetically pivotal lineages
to elucidate two groups of ancient gene duplications—one in the common
ancestor of extant seed plants and the other in the common ancestor of
extant angiosperms. Gene duplication events were intensely concentrated
around 319 and 192 million years ago, implicating two WGDs in ancestral
lineages shortly before the diversification of extant seed plants and
extant angiosperms, respectively. Significantly, these ancestral WGDs
resulted in the diversification of regulatory genes important to seed
and flower development, suggesting that they were involved in major
innovations that ultimately contributed to the rise and eventual
dominance of seed plants and angiosperms.
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ying he
Tel:+32 (0)9 331 37 58 fax:+32 (0)9 3313809
VIB Department of Plant Systems Biology, Ghent University
Technologiepark 927, 9052 Gent, BELGIUM
yinhe(a)psb.vib-ugent.be http://bioinformatics.psb.ugent.be/
Left brain has nothing right, right brain has nothing left.
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