UBA2 (SAE2) Recombinant Protein

Posttranslational modification of proteins by the addition of the small protein SUMO (see SUMO1; MIM 601912), or sumoylation, regulates protein structure and intracellular localization. SAE1 (MIM 613294) and UBA2 form a heterodimer that functions as a SUMO-activating enzyme for the sumoylation of proteins (Okuma et al., 1999 [PubMed 9920803]).[supplied by OMIM, Mar 2010]

Function: The heterodimer acts as a E1 ligase for SUMO1, SUMO2, SUMO3, and probably SUMO4. It mediates ATP-dependent activation of SUMO proteins followed by formation of a thioester bond between a SUMO protein and a conserved active site cysteine residue on UBA2/SAE2. Ref.11 Ref.12 Ref.16 Ref.22 Ref.23 Ref.24

Pathway: Protein modification; protein sumoylation.

Subunit structure: Heterodimer of SAE1 and UBA2/SAE2. The heterodimer corresponds to the two domains that are encoded on a single polypeptide chain in ubiquitin-activating enzyme E1. Interacts with UBE2I. Ref.11 Ref.16 Ref.22 Ref.23 Ref.24

Subcellular location: Cytoplasm. Nucleus. Note: Shuttles between the cytoplasm and the nucleus, sumoylation is required either for nuclear translocation or nuclear retention. Ref.11 Ref.21

Post-translational modification: Sumoylated with SUMO1 and SUMO2/3 and by UBC9. Sumoylation at Lys-236 inhibits enzymatic activity. Sumoylation at the C-terminal lysine cluster plays an essential role in nuclear trafficking. Ref.20 Ref.21

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