C-Mannosylation of human RNase 2 is an intracellular process performed by a variety of cultured cells.

Details

Serval ID
serval:BIB_05DA9A7BD2C4
Type
Article: article from journal or magazin.
Collection
Publications
Title
C-Mannosylation of human RNase 2 is an intracellular process performed by a variety of cultured cells.
Journal
Journal of Biological Chemistry
Author(s)
Krieg J., Gläsner W., Vicentini A., Doucey M.A., Löffler A., Hess D., Hofsteenge J.
ISSN
0021-9258 (Print)
ISSN-L
0021-9258
Publication state
Published
Issued date
1997
Volume
272
Number
42
Pages
26687-26692
Language
english
Abstract
C2-alpha-Mannosyltryptophan was discovered in RNase 2 from human urine, representing a novel way of attaching carbohydrate to a protein. Here, we have addressed two questions related to the biosynthesis of this modification: (i) is C-mannosylation part of the normal intracellular biosynthetic route, and (ii) how general is it, i.e. which organisms perform this kind of glycosylation? To answer the first question, RNase 2, which is identical to the eosinophil-derived neurotoxin, was isolated from intracellular stores of cultured human HL-60 cells. The enzyme was C-mannosylated at Trp-7, showing that the modification occurs intracellularly, before secretion of the protein. The second question was investigated by immunological and chemical analysis of RNase 2 purified from the supernatant of transiently transformed cells from different organisms. This revealed that C-mannosylation occurs in cells from man, green monkey, pig, mouse, and hamster. The observation that pig kidney cells contain the machinery for C-mannosylation of Trp-7 of human RNase 2 but that the homologous RNase from porcine kidney is not a substrate, since it does not contain a tryptophan at position 7, strongly suggests that C-mannosylated proteins other than RNase 2 exist. Recombinant RNase 2 isolated from insect cells, plant protoplasts, and Escherichia coli was not C-mannosylated. These results not only form the basis for further studies on the biochemical aspects of C-mannosylation but also have implications for the choice of cells for production of recombinant glycoproteins.
Keywords
Animals, Antibody Specificity, Cell Line, Cloning, Molecular, Endoribonucleases/genetics, Endoribonucleases/metabolism, Humans, Mass Spectrometry, Peptide Mapping, Tryptophan/analogs & derivatives, Tryptophan/metabolism
Pubmed
Web of science
Open Access
Yes
Create date
28/01/2008 8:28
Last modification date
20/08/2019 12:27
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