Ubiquitin Protein Ligase E3B (UBE3B)

The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes, or E1s, ubiquitin-conjugating enzymes, or E2s, and ubiquitin-protein ligases, or E3s. UBE3B encodes a member of the E3 ubiquitin-conjugating enzyme family. The encoded protein may interact with other proteins and play a role in stress response. Alternatively spliced transcript variants encoding the same protein isoform have been identified for this gene.The deduced 1,068-amino acid protein has a calculated molecular mass of about 123 kD, and the UBE3B transcript contains a 1.9-kb 3-prime untranslated region. Both mouse and human UBE3B contain an N-terminal IQ domain and a C-terminal HECT domain.