title: Identification of a 26S proteasome-associated UCH in fission yeast.
abstract: We have identified a 26S proteasome-associated ubiquitin carboxyl-terminal hydrolase (UCH) in Schizosaccharomyces pombe. The gene (designated uch2+) encodes a protein containing a UCH catalytic domain at its N-terminus and a short extension at its C-terminus. uch2+ is nonessential as the uch2 null mutant strain showed no significant difference from the wild-type strain. The GFP-tagged Uch2p is localized predominantly to the nuclear periphery, which is similar to the 26S proteasome localization. Deletion of the C-terminal extension of Uch2p resulted in a drastic change of its subcellular localization: it showed a generally diffused distribution instead of a perinuclear pattern. Glycerol gradient centrifugation analysis and coimmunoprecipitation studies of fission yeast extracts using anti-Mts4p antiserum suggest that Uch2p is associated with the 26S proteasome and the association of Uch2p with the 26S proteasome is mediated by its C-terminal extension.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, National University of Singapore, Singapore.
authors.forename: T
authors.initials: T
authors.lastname: Li
authors.forename: N I
authors.initials: NI
authors.lastname: Naqvi
authors.forename: H
authors.initials: H
authors.lastname: Yang
authors.forename: T S
authors.initials: TS
authors.lastname: Teo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005800:Genes, Fungal; D051379:Mice; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D010447:Peptide Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex; D012568:Schizosaccharomyces / Q000201:enzymology* / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013869:Thiolester Hydrolases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D043222:Ubiquitin Thiolesterase
chemical_list: D013869:Thiolester Hydrolases; D010447:Peptide Hydrolases; D043222:Ubiquitin Thiolesterase; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease