DegrAAAded into silence.

Wellcome Trust Centre for Cell Biology, University of Edinburgh, Kings Buildings, Michael Swann Building, Mayfield Road, Edinburgh, EH9 3JR, UK.

Cell 2007 May 18

In fission yeast, RNA interference (RNAi)-dependent heterochromatin formation silences transgenes inserted at centromeres. In this issue, Bühler et al. (2007) demonstrate that the RNAi machinery directly targets transgene transcripts. Furthermore, they link transgene silencing to a protein complex resembling the TRAMP complex of budding yeast, which promotes transcript degradation via the exosome. Thus, RNAi-independent transcript degradation may also contribute to heterochromatin gene silencing.