New romance between RNA degradation pathways: Mmi1 and RNAi meet on heterochromatic islands.
EMBO J 31 10, 2296–2308 (2012); published online April 20 2012 Meiosis is one of the most dramatic differentiation programmes a cell can undertake, since it leads to an irreversible reduction of the cell’s genetic content. It therefore comes as no surprise that meiosis should be tightly regulated. In this issue Hiriart et al (2012) identify a new layer of regulation in which the RNA interference (RNAi) pathway dampens the expression of meiotic genes during vegetative growth in fission yeast. Their study converges with a recent publication by Zofall et al (2012) to reveal how components of the RNAi pathway, the Mmi1 RNA elimination system and chromatin modifications contribute to the maintenance of the vegetative state until a decision is made to enter meiosis.
Holm LR, Thon G