Fig. 4
From: Epigenetic regulation of HIV-1 latency: focus on polycomb group (PcG) proteins
Schematic of types of PcG proteins: the PcG proteins are implicated in transcriptional silencing and formation of higher order chromatin structure. PcG proteins form three main complexes, PRC1, PRC2, and Pho-RC. Three principal PcG complexes have been described in D. melanogaster; and the human homologs are also shown. D. melanogaster proteins are shown in shapes (blue) while human homologs are drawn adjacent to these. PRC1 and PRC2 have been identified in mammals while PhoRC have only been characterized in D. melanogaster