Ub-Cys632-UBA1 adenylates ubiquitin in the cytosol

Stable Identifier
R-HSA-8852132
Type
Reaction
Species
Homo sapiens
Compartment
Locations in the PathwayBrowser
Summation

Activation of ubiquitin by UBA1 proceeds through 3 steps: adenylation of ubiquitin, conjugation of ubiquitin from adenyl-ubiquitin to an internal cysteine residue of UBA1, and adenylation of a second molecule of ubiquitin. In the third step, the UBA1-ubiquitin conjugate adenylates the C-terminal glycine of a second ubiquitin molecule. This results in UBA1 loaded with 2 ubiquitin molecules, one of which is conjugated to an internal cysteine residue of UBA1 and one of which is adenylated and non-covalently bound to UBA1 (Jin et al. 2007, inferred from the rabbit homologue in Haas et al. 1982, Hershko et al. 1983, reviewed in Groettrup et al. 2008).

Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
ubiquitin activating enzyme activity of Ub-Cys632-UBA1 [cytosol]
Physical Entity
Activity
Orthologous Events