Polycomb Repressive Complex 1

**Semantic type:** Amino Acid, Peptide, or Protein

**Definition:** A protein complex that represses transcription by stimulating chromatin compaction, inhibiting elongation by RNA polymerase II and monoubiquitinating lysine-119 of histone H2A. Canonical Polycomb repressive complex 1 (PRC1) is comprised of a core complex containing one RING1, one PCGF, one CBX and one HPH family protein. Additionally, non-canonical forms of PRC1 exist and are more diverse; they may include only some members of the canonical core protein families as well as other proteins not found in the canonical complex. These complexes are involved in embryonic development and X chromosome inactivation.

**Synonyms:** - PRC1