The Polycomb repressive complex PRC2. (A) Domain organization of each subunit in the human PRC2 complex. aa, amino acid; SBD, SANT1-binding domain; EBD, the EED-binding domain; BAM, β-addition motif; SAL, SET activation loop; SRM, stimulation-responsive motif; MCSS, motif connecting SANT1 and SANT2; SANT, SWI3, ADA2, N-CoR and TFIIIB DNA-binding domain; CXC, cysteine-rich domain; SET, Su(var) 3–9, enhancer of zeste, trithorax domain; WD, WD-40 domain; WDB, WD-40 binding domain; Zn, Zn-finger region; VEFS, conserved among VRN2-EMF2-FIS2-SU(Z)12; JmjN, Jumonji N; ARID, AT-rich interaction domain; JmjC, Jumonji C; PHD, plant homeodomain. (B) Model of the human PRC2 complex. EZH2, EED, SUZ12, and RbA48 are core subunits, while JARID2, PCLs, AEBP2 are auxiliary subunits. PRC2 complex catalyzes tri-methylation of H3K27, leading to compaction of nucleosome and transcription silencing.