Uba1 - ubiquitin-like modifier activating enzyme 1

This gene encodes a member of the ubiquitin-activating E1 family. The encoded protein initiates the ubiquitin activation and transfer cascade, catalyzing the first step in ubiquitin conjugation to mark cellular proteins for proteasome degradation. Ubiquitin activating enzymes use ATP to form a thioester between a conserved catalytic cysteine of the enzyme and the C-terminal carboxylate of ubiquitin. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2013]