RT Journal Article
SR Electronic
T1 Mutation rates in seeds and seed-banking influence substitution rates across the angiosperm phylogeny
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 156398
DO 10.1101/156398
A1 Marcel Dann
A1 Sidonie Bellot
A1 Sylwia Schepella
A1 Hanno Schaefer
A1 Aurélien Tellier
YR 2017
UL http://biorxiv.org/content/early/2017/06/27/156398.abstract
AB Background Seed-banking (the ability to persist in the soil over many generations) is usually considered as a dormant stage where genotypes are “stored” as a bet-hedging strategy in response to unpredictable environments. However, seed dormancy may instead have consequences for the integrity of the DNA and generate novel mutations.Methods We address this paradox by building phylogenies based on the plastomes and nuclear ITS of species belonging to ten angiosperm clades. In each clade, the substitution rate (branch-length) of a seed-banking species is compared with that of a closely-related non-seed-banking species.Results Seed-banking species show as high or higher substitution rates than non-seedbanking species, and therefore mutations occur in dormant seeds at a rate at least as high as in above-ground plants. Moreover, seed born mutations have the same probability to reach fixation as those from above ground. Our results are robust to differences in selection, generation time, and polymorphism.Conclusions Mutations occurring in seeds, and thus seed-banking, affect the population diversity of plant species, and are observable at the macro-evolutionary scale. Our study has consequences for seed storage projects, since the stored seeds are likely to accumulate mutations at a higher rate than previously thought.