High-performance liquid chromatography purification followed by mass spectrometry analyses highlighted that human senile cataractous lens includes a 8182 Da species which is absent in the normal lens, whereas a 8566/8583 Da species is present in both lenses. Western blot analysis identified both species as ubiquitin. The species at lower molecular weight is a shorter form due to the cleavage of the C-terminal residues 73-76. As it is the last amino acid of ubiquitin which is involved in the protein degradation mechanism, we suggest that this structure modification compromises the function of ubiquitin and consequently the physiologically occurring degradation of the lens proteins. © 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.
High-performance liquid chromatography purification followed by mass spectrometry analyses highlighted that human senile cataractous lens includes a 8182 Da species which is absent in the normal lens, whereas a 8566/8583 Da species is present in both lenses. Western blot analysis identified both species as ubiquitin. The species at lower molecular weight is a shorter form due to the cleavage of the C-terminal residues 73-76. As it is the last amino acid of ubiquitin which is involved in the protein degradation mechanism, we suggest that this structure modification compromises the function of ubiquitin and consequently the physiologically occurring degradation of the lens proteins. © 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.
Alteration in the ubiquitin structure and function in the human lens: A possible mechanism of senile cataractogenesis
STIUSO, Paola;LIBONDI, Teodosio;
2002
Abstract
High-performance liquid chromatography purification followed by mass spectrometry analyses highlighted that human senile cataractous lens includes a 8182 Da species which is absent in the normal lens, whereas a 8566/8583 Da species is present in both lenses. Western blot analysis identified both species as ubiquitin. The species at lower molecular weight is a shorter form due to the cleavage of the C-terminal residues 73-76. As it is the last amino acid of ubiquitin which is involved in the protein degradation mechanism, we suggest that this structure modification compromises the function of ubiquitin and consequently the physiologically occurring degradation of the lens proteins. © 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.