Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P62988 (Ubiquitin)
 4,326 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ultrastructural immunoreactivities of alpha B-crystallin, glial fibrillary acidic protein (GFAP), ubiquitin, and vimentin in Rosenthal fibers (RFs) isolated from an Alexander's disease brain were investigated using nonosmium and low-temperature embedding technique. The morphology of RFs embedded in Lowicryl K4M resin was well preserved after treatment with 0.5% Triton X-100. alpha B-crystallin immunoreactivity was present in RFs of various sizes and was the strongest in loosely scattered deposits, which were considered to be the initial stage of RFs. Glial fibrillary acidic protein immunoreactivity in RFs was heavy, homogeneous throughout RFs, and equivalent to that in networks of glial filaments. Immunoreactivities of both alpha B-crystallin and GFAP were mainly restricted to the high electron-dense areas within RFs and were proved to exist close to each other by double immunolabeling. Rosenthal fibers were negative for vimentin. Ubiquitin immunoreactivity was relatively homogeneous in RFs with small diameters, but in RFs with large diameters, the immunoreactivity diminished in the center. Based on these observations, combined with the tendency of self-aggregation of alpha B-crystallin, it is conceivable that RFs are huge aggregation products of alpha B-crystallin involving GFAP, and that ubiquitination may be a consequent phenomenon, as it may be in other intracytoplasmic inclusions, such as neurofibrillary tangles and Lewy bodies.
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PMID:Rosenthal fibers share epitopes with alpha B-crystallin, glial fibrillary acidic protein, and ubiquitin, but not with vimentin. Immunoelectron microscopy with colloidal gold. 170 36

The authors have shown previously that ubiquitin, a protein involved in the degradation of short-lived and abnormal proteins, is present in several cytoplasmic inclusions of neurons. This study used a library of antibodies to ubiquitin and immunohistochemically examined for the presence of ubiquitin in nonviral intracytoplasmic inclusions that form in different cell types under various pathologic conditions. Membrane-bound lysosomal and nonlysosomal inclusions such as those of storage disease, Russell bodies, alpha-1-antitrypsin and alpha-fetoprotein as well as nonmembrane-bound inclusions were examined. Ubiquitin epitopes were detected in some of the nonmembrane-bound inclusions only. The ubiquitin-containing inclusions were the Rosenthal fibers, Mallory bodies, Crooke bodies, Lafora bodies, amyloid bodies, and the giant axons of giant axonal neuropathy. Nemaline bodies and the inclusions of juvenile digital fibromatosis, both of which contain actin and actinbinding proteins, did not show immunoreaction. These findings, as well as those of the previous study, show that the presence of ubiquitin in cellular inclusions is selective. The ubiquitin-containing inclusions are not membrane bound; they are fibrillary and most contain also intermediate filament-related proteins. The role of ubiquitin in the formation of these inclusions remains to be elucidated.
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PMID:Selective presence of ubiquitin in intracellular inclusions. 246 1

Immunocytochemical localization of the cell stress-associated protein ubiquitin was performed on human lesions containing Rosenthal fibres. Ubiquitin was localized around the periphery of classical Rosenthal fibres but not in the amorphous central areas; the ubiquitin-positive regions corresponded to the immunocytochemical localization of glial fibrillary acidic protein (GFAP). Compact bundles of GFAP in glial processes without a non-staining core were also associated with ubiquitin, while loosely aggregated cellular GFAP was not. The relationship between compact bundles of GFAP and the amorphous osmiophilic central component of Rosenthal fibres has been uncertain. These data, however, show that the compact bundles of glial filaments are distinct from normal GFAP in being associated with ubiquitin. A role for ubiquitin in Rosenthal fibre formation is suggested. We propose that the term Rosenthal fibre be restricted to mean the hyaline amorphous core of these structures, while realizing that this is based on a wider abnormality of surrounding glial fibrillary acidic protein filaments.
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PMID:Rosenthal fibres are based on the ubiquitination of glial filaments. 254 26

Polyclonal antibodies were raised which have a high affinity for conjugated ubiquitin. Immunocytochemistry was performed on paraffin sections of tissues showing well-characterized inclusion bodies. Ubiquitin was found as a component of the intermediate filament inclusion bodies characteristic of several major diseases including Lewy bodies of Parkinson's disease, Pick bodies of Pick's disease, Mallory bodies of alcoholic liver disease, cytoplasmic bodies of a specific myopathy, and Rosenthal fibres within astrocytes. Ubiquitin was also present in the three histological lesions characteristic of Alzheimer's disease. These observations suggest a fundamental role for ubiquitin in the formation of intermediate filament inclusion bodies in man, and have implications regarding the pathogenesis of these important diseases.
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PMID:Ubiquitin is a common factor in intermediate filament inclusion bodies of diverse type in man, including those of Parkinson's disease, Pick's disease, and Alzheimer's disease, as well as Rosenthal fibres in cerebellar astrocytomas, cytoplasmic bodies in muscle, and mallory bodies in alcoholic liver disease. 283 58