Mechanisms of RNA-directed DNA methylation

Speaker: dr Andrzej T. Wierzbicki (University of Michigan Department of Molecular, Cellular, and Developmental Biology (MCDB), USA)

Talk: Mechanisms of RNA-directed DNA methylation

Time: 22 May 2017, 15pm

Venue: Intercollegiate Faculty of Biotechnology, Abrahama 58

RNA-directed DNA methylation is a conserved process where small RNAs target transposons and other sequences for repression by establishing chromatin modifications. A central element of this process is long noncoding RNA (lncRNA) which has been proposed to serve as a binding scaffold for small RNAs and associated proteins. In Arabidopsis thaliana, this lncRNA is produced by a specialized RNA polymerase known as Pol V. Pol V transcripts serve as a binding scaffold for several RNA-binding proteins, which mediate the recruitment of chromatin modifying enzymes. These enzymes contribute to the repression of transposon activity and help determine the boundaries between heterochromatic transposons and their euchromatic environment. RNA-directed DNA methylation has also been implicated in controlling organization of chromosomes, which may explain how it affects expression of distant genes.