Ubiquitin-conjugating enzyme E2 that specifically acts with HECT-type and RBR family E3 ubiquitin-protein ligases. Does not function with most RING-containing E3 ubiquitin-protein ligases because it lacks intrinsic E3-independent reactivity with lysine: in contrast, it has activity with the RBR family E3 enzymes, such as PARK2 and ARIH1, that function like function like RING-HECT hybrids. Accepts ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. In vitro catalyzes 'Lys-11'-linked polyubiquitination. Involved in the selective degradation of short-lived and abnormal proteins. Down- regulated during the S-phase it is involved in progression through the cell cycle. Regulates nuclear hormone receptors transcriptional activity. May play a role in myelopoiesis. Interacts with PARK2; involved in ubiquitination and degradation of misfolded proteins. Interacts with UBE3A; used by the papilloma virus HPV-16 E6 protein to ubiquitinate p53/TP53. Interacts with CCNB1IP1, CBL, ZAP70, RNF19A, RNF19B and RNF144B. Interacts with ARIH1. Interacts with ARIH2 (via RING-type 1). Interacts with NCOA1; they functionally interact to regulate progesterone receptor transcriptional activity. May interact with NR3C1. Ubiquitous, with highest expression in testis. Belongs to the ubiquitin-conjugating enzyme family. Note: This description may include information from UniProtKB.
Molecular Function: protein binding; acid-amino acid ligase activity; enzyme binding; ubiquitin protein ligase binding; transcription coactivator activity; ubiquitin-protein ligase activity; ATP binding
Biological Process: ubiquitin-dependent protein catabolic process; cell proliferation; protein polyubiquitination; transcription, DNA-dependent; regulation of transcription, DNA-dependent; protein modification process; protein ubiquitination
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.