Skip to main content

Table 1 PcG proteins core complex components in D. melanogaster and human

From: Epigenetic regulation of HIV-1 latency: focus on polycomb group (PcG) proteins

PcG subunits in Drosophila melanogaster PcG subunits in humans Protein domains Biochemical functions
Polycomb-repressive complex 1 (PRC1)
 Polyhomeotic proximal (PH-P) and distal (PH-D) PHC-1/EDR1,
C2-C2 zinc-finger and SAM Domain Higher order interaction?
 Posterior sex comb (PSC)/suppressor 2 of Zeste (Su(z)2) BMI1/PCGF4
Ring finger domain
(C3HC4 Zinc-finger)
Co-factor for SCE and compacts chromatin
 Polycomb (PC) CBX2/HPC1
CBX6, CBX7 and CBX8/HPC3
Shadow domain and chromodomain Binds to H3K27 trimethylation marks and CBX4 is reported to be a SUMO E3-ligase
 Sex comb extra (SCE)/dRING RING1/RING1A, RNF1
Ring-finger domain
(C3HC4 Zinc-finger)
Ubiquitinates H2AK118 (H2AK119 in vertebrates) and compacts the chromatin
 Sex comb on midleg (SCM) SCMH1
MBTs, SAM, DUF3588 and Zinc-finger and SPM domain ?
Polycomb-repressive complex 2 (PRC2)
 Enhancer of Zeste (E(z)) EZH1 and EZH2/KMT6 CXC domain, SET domain, SANT and homolog domain I and II Catalyzes trimethylation (H3K27)
 Suppressor of Zeste 12 (Su(z)12) SUZ12 C2-H2 Zinc-finger, VEFS Box, alanine rich and Glycine rich Enhances the enzymatic activities of EZ and also important for nucleosome binding
 Extra sex comb (ESC) EED or WAIT-1 WD-40 repeats Stimulates H3K27 methyltransferase
 Extra sex comb like (ESCL)
 Chromatin assembly factor 1 (Caf1)/nucleosome remodeling factor 55 (Nurf55) RbAp46/RBBP7
WD-40 repeats Binds to histones and suppressor of Zeste 12
 Polycomb-like (PCL) PHF1/PCL1
PHD finger and tudor domain Induces trimethylations and recruits PRC2
Pleiohomeotic (Pho)-repressive complex (Pho-RC)
 PHO YY1, YY2 Zinc-finger DNA binding
 SFMBT (CG16975)   MBT and SAM Bind to mono- and dimethylated histone at H3K9 and H4K20