title: Proteasome regulation, plant growth and stress tolerance.
abstract: Plant cells contain a mixture of 26S and 20S proteasomes that mediate ubiquitin-dependent and ubiquitin-independent proteolysis, respectively. The 26S proteasome contains the 20S proteasome and one or two regulatory particles that are required for ubiquitin-dependent degradation. Comparative analyses of Arabidopsis proteasome mutants revealed that a decrease in 26S proteasome biogenesis causes heat shock hypersensitivity and reduced cell division rates that are compensated by increased cell expansion. Loss of 26S proteasome function also leads to an increased 20S proteasome biogenesis, which in turn enhances the cellular capacity to degrade oxidized proteins and thus increases oxidative stress tolerance. These findings suggest the intriguing possibility that 26S and 20S proteasome activities are regulated to control plant development and stress responses. This mini-review highlights some of the recent studies on proteasome regulation in plants.
authors.affiliation: Plant Physiology, Biochemistry, Molecular Biology Program, Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, USA.
authors.forename: Jasmina
authors.initials: J
authors.lastname: Kurepa
authors.forename: Songhu
authors.initials: S
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Jan
authors.initials: J
authors.lastname: Smalle
mesh_terms: D000222:Adaptation, Physiological; D017360:Arabidopsis / Q000166:cytology / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002455:Cell Division; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D009154:Mutation; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D013312:Stress, Physiological; D025801:Ubiquitin / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D025801:Ubiquitin; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease