E3 ubiquitin-protein ligase required to prevent centriole reduplication (, ). Probably acts by ubiquitinating positive regulators of centriole reduplication . Mediates monoubiquitination of 'Lys-119' of histone H2A (H2AK119Ub), a specific tag for epigenetic transcriptional repression: associates with some Polycomb group (PcG) multiprotein PRC2-like complex and mediates repression of target genes . Also acts as a positive regulator of peroxisome import by mediating monoubiquitination of PEX5 at 'Lys-472': monoubiquitination promotes PEX5 stabilitation by preventing its polyubiquitination and degradation by the proteasome . Has anti-HIV activity .
Subcellular locations: Chromosome, Cytoplasm, Perinuclear region, Peroxisome membrane
Found in vesicles of the peroxisome. Aggregates as aggresomes, a perinuclear region where certain misfolded or aggregated proteins are sequestered for proteasomal degradation.
Ubiquitous . Highly expressed in testis, while it is weakly expressed in other tissues .