In eukaryotes, which of the following is covalently linked to the protein that is targeted for destruction?
The selective degradation of many sho-lived proteins in eukaryotic cells is carried out by the ubiquitin-mediated proteolytic system. In this pathway, proteins are targeted for degradation by covalent ligation to ubiquitin. Ref: The Ubiquitin-Proteasome Proteolytic System, By Aaron J. Ciechanover, Maria G. Masucci, 2002 ; Progress In Virus Research By Sabine Thebault, Page 79, Structural And Functional Organization Of The Synapse By Johannes W. Hell, Michael D. Ehlers
Clathrin
Pepsin
Laminin
Ubiquitin