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

A Ubiquitin-like peptide was accidentally isolated from rat bladder by using 5% acetic acid wash while we were isolating antibacterial peptides. The purified molecule was obtained by reverse phase high performance liquid chromatography. Gas phase microsequence analysis indicated the N-terminal sequences of the molecule as follows: MET-GLN-ILE-PHE-VAL-LYS-THR-LEU-THR-GLY-LYS-THR-ILE-THR-LEU- GLU-VAL-GLU-PRO-SER-ASP-THR-ILE-GLU-ASN, which is homologous to human ubiquitin. Ubiquitin plays a role in the differentiation of pre-B lymphocytes, Thus, it is suggested from the findings of this molecule and the endogenous antibacterial polypeptides in mucosa or mucosal epithelium that mucosal epithelium also might be one of immune cells or immunity-associated cells, which may secrete effector molecules directly to kill adherent microbes and produce regulating factors in mucosal immune response.
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PMID:[Rat bladder ubiquitin-like molecule: isolation, purification and N-terminal sequencing]. 824 87

The subject presented with intellectual decline followed by progressive muscle weakness of the bilateral upper limbs when he was 60 years old. He had a point mutation (methionin-valine) at 129 prion protein codon. He died at the age of 63 and necropsy revealed bilateral frontal lobe atrophy. The frontal cortex showed neuronal cell loss in layers II and III with spongiform change. Reusche silver impregnation technique for beta-peptide combined with ubiquitin immunostaining revealed perineuronal structures encircling degenerated neurons and ubiquitin-immunoreactive (IR) dot-like deposits. They were distributed particularly in the temporal neocortex and entorhinal cortex. They differed from either classic senile or diffuse plaque by the absence of amyloid core in the center and of amyloid fibrils. Ubiquitin-IR materials were also found as neuronal inclusions in the hippocampal granular cells. Nigral degeneration and neuronal loss in the hypoglossal nerve nucleus and in the anterior horn of the spinal cord were also found and spinal cord motoneurons had Bunina body inclusions. The clinical features and pathological findings were consistent with non-Alzheimer dementia with status spongiosus and neuronal cell loss. The unusual perineuronal structures found in our case might be a specific cellular pathology of dementia of the frontal lobe type.
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PMID:Non-Alzheimer dementia with status spongiosus and neuronal cell loss showing unusual perineuronal structures and point mutation at 129 codon of prion protein. 899 53

Ubiquitin is expressed in eukaryotic cells as precursors, fused via its carboxyl terminus either to other ubiquitin sequences in linear polyubiquitin arrays or to specific ribosomal proteins. In some of the polyubiquitin fusions a single amino acid (e.g., valine in humans) is attached to the carboxyl terminus. These gene products are rapidly (probably cotranslationally) cleaved by ubiquitin carboxyl-terminal hydrolase (UCH) enzymes; therefore, although ubiquitin precursors are suitable substrates for assays of UCH activity, they are difficult to isolate from nucleated cells. While the recombinant approach allows the production of ubiquitin precursors in prokaryotic cells (which do not contain the ubiquitin system), proteins produced in this manner require purification and may also be susceptible to modification by bacterial enzymes, e.g., adventitious proteolysis. As an alternative we have chemically synthesized human ubiquitin-valine. In the assay described here the cleavage of ubiquitin-valine to ubiquitin (77 and 76 residue proteins, respectively) by a purified recombinant Drosophila UCH was monitored by capillary electrophoresis. Mass spectrometry verified the precise cleavage of ubiquitin-valine, confirming that this synthetic protein is a UCH substrate. Synthetic ubiquitin-valine may serve as a generic substrate for UCHs allowing the purification and identification of new members of this enzyme family.
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PMID:Capillary electrophoresis assay for ubiquitin carboxyl-terminal hydrolases with chemically synthesized ubiquitin-valine as substrate. 917 92