Towards Understanding Basal Angiosperm Diversification: Recent Insights Using Rapidly Evolving Genomic Regions

Borsch T, Löhne C, Müller KF, Hilu KW, Wanke S, Worberg A, Barthlott W, Neinhuis C, Quandt D

Forschungsartikel (Zeitschrift)

Zusammenfassung

The prevailing view in molecular phylogenetics is that relationships at deeper levels, for example among major angiosperm lineages, should be inferred using rather conserved genes. Rapidly evolving DNA has been deemed unsuitable because of putative high levels of homoplasy caused by multiple substitutions and frequent microstructural mutations resulting in their non-alignability. Recent analyses of rapidly evolving spacers and introns in the chloroplast genome from basal angiosperms show that extreme sequence variability is confined to certain mutational hotspots. These hotspots correlate with structural elements (stem loops), where selective pressure is low. Phylogenetic trees of basal angiosperms inferred from rapidly evolving genomic regions are well resolved and highly supported statistically. Reasons are not only greater amounts of informative sites in rapidly evolving DNA, but also differing levels of homoplasy that can result in better phylogenetic signal per informative site. Based on these findings, perspectives for further utilizing non-coding DNA in angiosperm phylogenetic studies are explored.

Details zur Publikation

Seiten: 26
Veröffentlichungsjahr: 2005
Sprache, in der die Publikation verfasst ist: Englisch