This gene encodes a nuclear-localized ubiquitin-conjugating enzyme (E2) that, along with ubiquitin-activating (E1) and ligating (E3) enzymes, coordinates the addition of a ubiquitin moiety to existing proteins. The encoded protein promotes the ubiquitination of Fanconi anemia complementation group proteins and may be important in the repair of DNA damage. There is a pseudogene for this gene on chromosome 1. Alternative splicing results in multiple transcript variants.