Regulatory mechanisms involved in the control of ubiquitin homeostasis.
Ubiquitin (Ub) modification plays an essential role in the regulation of various cellular processes. Ub performs a remarkable array of cellular tasks through the production of a large number of ubiquitinated proteins; such tasks require many Ubs. Ubs are expressed abundantly from several Ub encoding genes, though not in excess. Rather, Ub expression is tightly regulated through various control mechanisms. Recent studies have shown that the cellular Ub level is regulated by balanced activities of deubiquitinating enzymes and their regulators. Here, we review the current understandings of the regulatory mechanisms that control Ub expression and its metabolism and maintain Ub homeostasis.
Kimura
Yoko
Y
Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan. kimura-yk@igakuken.or.jp
Tanaka
Keiji
K
D000818:Animals; D005786:Gene Expression Regulation; D006706:Homeostasis; D006801:Humans; D051379:Mice; D008954:Models, Biological; D046988:Proteasome Endopeptidase Complex / Q000502:physiology*; D011499:Protein Processing, Post-Translational; D013312:Stress, Physiological / Q000502:physiology*; D025801:Ubiquitin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination / Q000502:physiology*
D025801:Ubiquitin; D046988:Proteasome Endopeptidase Complex