title: Polyubiquitin chains: polymeric protein signals.
abstract: The 76-residue protein ubiquitin exists within eukaryotic cells both as a monomer and in the form of isopeptide-linked polymers called polyubiquitin chains. In two well-described cases, structurally distinct polyubiquitin chains represent functionally distinct intracellular signals. Recently, additional polymeric structures have been detected in vivo and in vitro, and several large families of proteins with polyubiquitin chain-binding activity have been discovered. Although the molecular mechanisms governing specificity in chain synthesis and recognition are still incompletely understood, the scope of signaling by polyubiquitin chains is likely to be broader than originally envisioned.
authors.affiliation: Department of Biochemistry and Molecular Biology, Johns Hopkins University, Baltimore, MD 21205, USA. cpickart@jhmi.edu
authors.forename: Cecile M
authors.initials: CM
authors.lastname: Pickart
authors.forename: David
authors.initials: D
authors.lastname: Fushman
mesh_terms: D000818:Animals; D019281:Dimerization; D008239:Lysine / Q000378:metabolism; D025821:Polyubiquitin / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D015398:Signal Transduction; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism
chemical_list: D025821:Polyubiquitin; D044767:Ubiquitin-Protein Ligases; D008239:Lysine