Biomaterial Database

Ubiquitin recognition by the proteasome. 2017

Yasushi Saeki

Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.

The 26S proteasome is a 2.5-MDa complex responsible for the selective, ATP-dependent degradation of ubiquitylated proteins in eukaryotic cells. Substrates in hundreds cellular pathways are timely ubiquitylated and converged to the proteasome by direct recognition or by multiple shuttle factors. Engagement of substrate protein triggers conformational changes of the proteasome, which drive substrate unfolding, deubiquitylation and translocation of substrates to proteolytic sites. Recent studies have challenged the previous paradigm that Lys48-linked tetraubiquitin is a minimal degradation signal: in addition, monoubiquitylation or multiple short ubiquitylations can serve as the targeting signal for proteasomal degradation. In this review, I highlight recent advances in our understanding of the proteasome structure, the ubiquitin topology in proteasome targeting, and the cellular factors that regulate proteasomal degradation.

UI	MeSH Term	Description	Entries
D008239	Lysine	An essential amino acid. It is often added to animal feed.	Enisyl,L-Lysine,Lysine Acetate,Lysine Hydrochloride,Acetate, Lysine,L Lysine
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000074405	Valosin Containing Protein	A highly-conserved AAA ATPase that functions in the biogenesis of the transitional ENDOPLASMIC RETICULUM and fragmentation and reassembly of the GOLGI APPARATUS during MITOSIS. It also functions in a complex with UFD1L and NPLOC4 proteins to export misfolded ubiquitinated proteins from the endoplasmic reticulum and outer mitochondrial membrane to the cytoplasm for degradation by the PROTEASOME and also plays a role in AUTOPHAGY of ubiquitinated proteins. It occurs in neuronal INCLUSION BODIES from patients with AMYOTROPHIC LATERAL SCLEROSIS and LEWY BODIES from PARKINSON DISEASE patients.	CDC48 Protein,Cell Cycle Protein CDC48,Cell Cycle Protein CDC48p,Valosin-Containing Protein,Valosine-Containing Protein,p97 Valosin-Containing Protein,Valosin-Containing Protein, p97,Valosine Containing Protein,p97 Valosin Containing Protein
D000251	Adenosine Triphosphatases	A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.	ATPases,Adenosinetriphosphatase,ATPase,ATPase, DNA-Dependent,Adenosine Triphosphatase,DNA-Dependent ATPase,DNA-Dependent Adenosinetriphosphatases,ATPase, DNA Dependent,Adenosinetriphosphatases, DNA-Dependent,DNA Dependent ATPase,DNA Dependent Adenosinetriphosphatases,Triphosphatase, Adenosine
D015398	Signal Transduction	The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.	Cell Signaling,Receptor-Mediated Signal Transduction,Signal Pathways,Receptor Mediated Signal Transduction,Signal Transduction Pathways,Signal Transduction Systems,Pathway, Signal,Pathway, Signal Transduction,Pathways, Signal,Pathways, Signal Transduction,Receptor-Mediated Signal Transductions,Signal Pathway,Signal Transduction Pathway,Signal Transduction System,Signal Transduction, Receptor-Mediated,Signal Transductions,Signal Transductions, Receptor-Mediated,System, Signal Transduction,Systems, Signal Transduction,Transduction, Signal,Transductions, Signal
D044767	Ubiquitin-Protein Ligases	A diverse class of enzymes that interact with UBIQUITIN-CONJUGATING ENZYMES and ubiquitination-specific protein substrates. Each member of this enzyme group has its own distinct specificity for a substrate and ubiquitin-conjugating enzyme. Ubiquitin-protein ligases exist as both monomeric proteins multiprotein complexes.	Ubiquitin-Protein Ligase,E3 Ligase,E3 Ubiquitin Ligase,Ubiquitin Ligase E3,Ubiquitin-Protein Ligase E3,Ligase E3, Ubiquitin,Ligase E3, Ubiquitin-Protein,Ligase, E3,Ligase, E3 Ubiquitin,Ligase, Ubiquitin-Protein,Ligases, Ubiquitin-Protein,Ubiquitin Ligase, E3,Ubiquitin Protein Ligase,Ubiquitin Protein Ligase E3,Ubiquitin Protein Ligases
D046988	Proteasome Endopeptidase Complex	A large multisubunit complex that plays an important role in the degradation of most of the cytosolic and nuclear proteins in eukaryotic cells. It contains a 700-kDa catalytic sub-complex and two 700-kDa regulatory sub-complexes. The complex digests ubiquitinated proteins and protein activated via ornithine decarboxylase antizyme.	20S Proteasome,Ingensin,Macropain,Macroxyproteinase,Multicatalytic Endopeptidase Complex,Multicatalytic Proteinase,Prosome,Proteasome,Complex, Multicatalytic Endopeptidase,Complex, Proteasome Endopeptidase,Endopeptidase Complex, Multicatalytic,Endopeptidase Complex, Proteasome,Proteasome, 20S,Proteinase, Multicatalytic
D057149	Ubiquitinated Proteins	Proteins covalently modified with UBIQUITINS or UBIQUITIN-LIKE PROTEINS.	Proteins, Ubiquitinated
D059748	Proteolysis	Cleavage of proteins into smaller peptides or amino acids either by PROTEASES or non-enzymatically (e.g., Hydrolysis). It does not include Protein Processing, Post-Translational.	Protein Degradation,Protein Digestion,Degradation, Protein,Degradations, Protein,Digestion, Protein,Digestions, Protein,Protein Degradations,Protein Digestions,Proteolyses