Epigenetic silencing of transposable elements: a trade-off between reduced transposition and deleterious effects on neighboring gene expression.

ABSTRACT: Transposable elements (TEs) are ubiquitous genomic parasites. The deleterious consequences of the presence and activity of TEs have fueled debate about the evolutionary forces countering their expansion. Purifying selection is thought to purge TE insertions from the genome, and TE sequences are targeted by hosts for epigenetic silencing. However, the interplay between epigenetic and evolutionary forces countering TE expansion remains unexplored. Here we analyze genomic, epigenetic, and population genetic data from Arabidopsis thaliana to yield three observations. First, gene expression is negatively correlated with the density of methylated TEs. Second, the signature of purifying selection is detectable for methylated TEs near genes but not for unmethylated TEs or for TEs far from genes. T

SUBMITTER: Hollister JD 

PROVIDER: S-EPMC2720190 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature