UBE4B, HDNB1, KIAA0684, UFD2, Ubiquitin conjugation factor E4 B, Homozygously deleted in neuroblastoma 1, Ubiquitin fusion degradation protein 2
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. This gene encodes an additional conjugation factor, E4, which is involved in multiubiquitin chain assembly. This gene is also the strongest candidate in the neuroblastoma tumor suppressor genes. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008],function:Binds to the ubiquitin moieties of preformed conjugates and catalyzes ubiquitin chain assembly in conjunction with E1, E2, and E3.,PTM:Proteolytically cleaved by caspases during apoptosis. Cleaved efficiently at Asp-123 by caspase-6 and granzyme B. Cleaved with approximately 10-fold less efficiency at Asp-109 by caspase-3 and caspase-7.,similarity:Belongs to the ubiquitin conjugation factor E4 family.,similarity:Contains 1 U-box domain.,subunit:Interacts with VCP.,tissue specificity:Highest expression in ovary, testis, heart and skeletal muscle. Expression is low in colon, thymus and peripheral blood leukocytes. Almost undetectable in lung and spleen.,
