Molecular CelL: Beringuer M, Di Croce L.

Linking Polycomb with Elongin. EPOP (elongin and polycomb-associated protein) binds to Polycomb repressive complex 2 (PRC2, in blue) and to Elongin BC (in yellow). In this issue, two papers by Beringer et al. (pp. 645–658) and by Liefke et al. (pp. 659–672) report that EPOP, a recently identified PRC2-associated factor, serves to bring Elongin BC to chromatin in embryonic stem cells. At genomic sites, EPOP and Elongin fine-tune chromatin architecture and expression levels of target genes. Cover image contributed by the Di Croce laboratory and designed by Iris Joval Granollers.