Component of a Polycomb group (PcG) multiprotein PRC1-like complex, a complex class required to maintain the transcriptionally repressive state of many genes, including Hox genes, throughout development. PcG PRC1 complex acts via chromatin remodeling and modification of histones; it mediates monoubiquitination of histone H2A 'Lys-119', rendering chromatin heritably changed in its expressibility. In the PRC1-like complex, regulates the E3 ubiquitin-protein ligase activity of RNF2/RING2. Component of a PRC1-like complex. During early nervous system development, robust expression was observed in the open neural plate and later in the dorsal neural tube and much of the brain. Also present in the developing heart primordia and the sensory placodes.