FunctionEnhances the sumoylation of a number of proteins including HIF1A, PIAS and I-kappa-B, through direct interaction with UBC9. Has no effect on ubiquitination.
Tissue specificityExpressed in a wide number of tissues with highest expression in cerebellum, pituitary, heart, kidney, liver, stomach, pancreas, prostate and spleen. Low levels in thalamus, spinal cord, esophagus, thymus, lung and peripheral blood leukocytes.
Sequence similaritiesContains 1 RWD domain.
DomainThe RWD domain is required for the sumoylation enhancement activity.
Cellular localizationNucleus. Cytoplasm. Colocalizes with UBC9/UBE2I in nuclear spots.