UBA5 Full-Length MS Protein Standard (NP_079094), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. This gene encodes a member of the E1-like ubiquitin-activating enzyme family. This protein activates ubiquitin-fold modifier 1, a ubiquitin-like post-translational modifier protein, via the formation of a high-energy thioester bond. Two alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. A pseudogene located on chromosome 1 has also been identified.