Crystal structures of Lys-63-linked tri- and di-ubiquitin reveal a highly extended chain architecture.
Weeks, S.D., Grasty, K.C., Hernandez-Cuebas, L., Loll, P.J.(2009) Proteins 77: 753-759
- PubMed: 19731378 
- DOI: 10.1002/prot.22568
- Primary Citation of Related Structures:  
3H7P, 3H7S - PubMed Abstract: 
The covalent attachment of different types of poly-ubiquitin chains signal different outcomes for the proteins so targeted. For example, a protein modified with Lys-48-linked poly-ubiquitin chains is targeted for proteasomal degradation, whereas Lys-63-linked chains encode nondegradative signals ...