Activating the ubiquitin family: UBA6 challenges the field.
Since its discovery in 1981, ubiquitin-activating enzyme 1 was thought to be the only E1-type enzyme responsible for ubiquitin activation. Recently, a relatively uncharacterized E1 enzyme, designated ubiquitin-like modifier activating enzyme 6, was also shown to activate ubiquitin. Ubiquitin-activating enzyme 1 and ubiquitin-like modifier activating enzyme 6 are both essential proteins, and each uses a different spectrum of ubiquitin-conjugating (E2) enzymes. Ubiquitin-like modifier activating enzyme 6 activates not only ubiquitin, but also the ubiquitin-like modifier FAT10 (human leukocyte antigen F-associated transcript 10), which, similarly to ubiquitin, serves as a signal for proteasomal degradation. This new layer of regulation in ubiquitin activation markedly increases the versatility of the ubiquitin conjugation system.
Groettrup
Marcus
M
Division of Immunology, Department of Biology, University of Constance, D-78457 Konstanz, Germany.
Pelzer
Christiane
C
Schmidtke
Gunter
G
Hofmann
Kay
K
D019143:Evolution, Molecular; D006801:Humans; D008958:Models, Molecular; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D044764:Ubiquitin-Activating Enzymes / Q000235:genetics / Q000378:metabolism; D014452:Ubiquitins / Q000235:genetics / Q000502:physiology*
C521757:UBA6 protein, human; C109184:UBD protein, human; D014452:Ubiquitins; D044764:Ubiquitin-Activating Enzymes