Active DNA Demethylation in Plant Companion Cells Reinforces Transposon Methylation in Gametes

摘要: The Arabidopsis thaliana central cell, the companion cell of egg, undergoes DNA demethylation before fertilization, but targeting preferences, mechanism, and biological significance this process remain unclear. Here, we show that active mediated by DEMETER glycosylase accounts for all in preferentially targets small, AT-rich, nucleosome-depleted euchromatic transposable elements. vegetative sperm, also DEMETER-dependent similar sequences, lack cells causes reduced small RNA-directed methylation transposons sperm. Our results demonstrate reinforces transposon plant gametes likely contributes to stable silencing elements across generations.