Rate, spectrum, and evolutionary dynamics of spontaneous epimutations.

Autor: van der Graaf, Adriaan, Wardenaar, René, Neumann, Drexel A., Taudt, Aaron, Shaw, Ruth G., Jansen, Ritsert C., Schmitz, Robert J., Colomé-Tatché, Maria, Johannes, Frank
Předmět:
Zdroj: Proceedings of the National Academy of Sciences of the United States of America; 5/26/2015, Vol. 112 Issue 21, p6676-6681, 6p
Abstrakt: Stochastic changes in cytosine methylation are a source of heritable epigenetic and phenotypic diversity in plants. Using the model plant Arabidopsis thaliana, we derive robust estimates of the rate at which methylation is spontaneously gained (forward epimutation) or lost (backward epimutation) at individual cytosines and construct a comprehensive picture of the epimutation landscape in this species. We demonstrate that the dynamic interplay between forward and backward epimutations is modulated by genomic context and show that subtle contextual differences have profoundly shaped patterns of methylation diversity in A. thaliana natural populations over evolutionary timescales. Theoretical arguments indicate that the epimutation rates reported here are high enough to rapidly uncouple genetic from epigenetic variation, but low enough for new epialleles to sustain long-term selection responses. Our results provide new insights into methylome evolution and its population-level consequences. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index