E3 ubiquitin-protein ligase. Plays an important role in regulating the surface level of MUSK on myotubes. Mediates the ubiquitination of MUSK, promoting its endocytosis and lysosomal degradation. Might contribute to terminal myogenic differentiation.
Subcellular locations: Synapse, Cytoplasm
Localizes to the postsynaptic region of neuromuscular junctions.
Widely expressed, including in the heart, skeletal muscle and liver and, at lower levels, in the brain, colon, small intestine, placenta and lung. Down-regulated in ovarian serous papillary tumors.