RRC ID 11759
Author Pellicer J, Garcia S, Canela MA, Garnatje T, Korobkov AA, Twibell JD, Vallès J.
Title Genome size dynamics in Artemisia L. (Asteraceae): following the track of polyploidy.
Journal Plant Biol (Stuttg)
Abstract Polyploidy is a key factor in the evolution of higher plants and plays an important role in the variation of plant genomes, leading to speciation in some cases. During polyploidisation, different balancing processes take place at the genomic level that can promote variation in nuclear DNA content. We estimated genome size using flow cytometry in 84 populations of 67 Artemisia species and one population of Crossostephium chinense. A total of 73 sequences of nrDNA ITS and 3'-ETS were newly generated and analysed, together with previously published sequences, to address the evolution of genome size in a phylogenetic framework. Differences in 2C values were detected among some lineages, as well as an increase of genome size heterogeneity in subgenera whose phylogenetic relationships are still unclear. We confirmed that the increase in 2C values in Artemisia polyploids was not proportional to ploidy level, but 1Cx genome size tended to decrease significantly when high ploidy levels were reached. The results lead us to hypothesise that genome size in polyploids tends to a maximum as it follows saturation behaviour, in agreement with the Michaelis-Menten model. We tested different arithmetic functions with our dataset that corroborated a non-linear relationship of genome size increase in polyploids, allowing us to suggest a theoretical upper limit for the DNA content of this genus.
Volume 12(5)
Pages 820-30
Published 2010-9-1
DOI 10.1111/j.1438-8677.2009.00268.x
PMID 20701707
MeSH Artemisia / genetics* DNA, Plant / genetics DNA, Ribosomal Spacer Flow Cytometry Genome, Plant* Phylogeny Polyploidy* Sequence Analysis, DNA
IF 2.393
Times Cited 49