UBA3 (UBE1C) Recombinant Protein

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 a member of the E1 ubiquitin-activating enzyme family. The encoded enzyme associates with AppBp1, an amyloid beta precursor protein binding protein, to form a heterodimer, and then the enzyme complex activates NEDD8, a ubiquitin-like protein, which regulates cell division, signaling and embryogenesis. Multiple alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Function: Catalytic subunit of the dimeric UBA3-NAE1 E1 enzyme. E1 activates NEDD8 by first adenylating its C-terminal glycine residue with ATP, thereafter linking this residue to the side chain of the catalytic cysteine, yielding a NEDD8-UBA3 thioester and free AMP. E1 finally transfers NEDD8 to the catalytic cysteine of UBE2M. Down-regulates steroid receptor activity. Necessary for cell cycle progression. Ref.6 Ref.7 Ref.8

Enzyme regulation: Binding of TP53BP2 to the regulatory subunit NAE1 decreases activity.

Pathway: Protein modification; protein neddylation.

Subunit structure: Heterodimer of UBA3 and NAE1. Interacts with NEDD8, UBE2F and UBE2M. Binds ESR1 and ESR2 with bound steroid ligand

By similarity. Interacts with TBATA

By similarity. Ref.8

Tissue specificity: Ubiquitously expressed. Ref.6

Miscellaneous: Arg-211 acts as a selectivity gate, preventing misactivation of ubiquitin by this NEDD8-specific E1 complex.

Sequence similarities: Belongs to the ubiquitin-activating E1 family. UBA3 subfamily.

Sequence caution: The sequence AAC27648.1 differs from that shown. Reason: Erroneous initiation.