Uba3 - ubiquitin-like modifier activating enzyme 3

The protein encoded by this gene is the catalytic subunit of the enzyme that activates NEDD8, a ubiquitin-like molecule that binds to its target proteins through an enzymatic reaction analagous to ubiquitylation. Embryonic mice deficient for this protein die prior to implantation and display apoptosis of the inner cell mass. Trophoblastic cells cannot enter S phase, demonstrating that this gene is required for cell cycle progression during embryogenesis. Two pseudogenes have been found for this gene. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Sep 2014]