Ubiquitin from bovine erythrocytes can be used for in vitro ubiquitinylation assay. The product can also be used as a marker in western blotting.
A 76-amino acid protein (8.6?kDa) that is bound covalently by a conjugating enzyme to proteins that are targeted for degradation by 26S proteasome. Occurs in virtually all eukaryotes, including plants (thus, its name). The sequence is highly conserved; identical in animal sources from insects to humans.
Ubiquitin is a small regulatory protein present in eukaryote tissues. Exogenous ubiquitin can stimulate apoptosis in numerous cell lines. E7 protein of human papilloma virus-16 stimulates Retinoblastoma Protein degradation via Ubiquitin-Proteasome Pathway.
