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Journal articles
Accumulation of UDP-GlcNAc into intracellular vesicles and occurrence of a carrier-mediated transport. Study with plasma-membrane-permeabilized mouse thymocytes
Abstract : Metabolic labelling of mouse thymocytes with radioactive mannose or glucosamine leads to the formation of labelled GDP-Man and UDP-ClcNAc. Using isotonic ammonium chloride treatment which renders the plasma membrane of thymocytes permeable to sugar nucleotides, we demonstrate that, in contrast to GDP-Man, a pool of UDP-GlcNAc remains associated with the cells after plasma membrane permeabilization. These observations are confirmed in experiments in which permeabilized thymocytes are incubated with exogenous labelled GDPMan and UDP-GlcNAc, and we show that only UDP-GlcNAc is accumulated into sealed intracellular vesicles. This accumulation is a saturable process which can be inhibited by UDP, demonstrating the occurrence of a specific carrier. This transport mechanism can be blocked by covalent attachment of a non-permeant inhibitor UDP-dialdehyde without affecting the N-acetylglucosaminyltransferase itself. The fact that this carrier-mediated transport is not inhibited by tunicamycin indicates that this translocation process of UDP-GlcNAc does not involve lipid intermediates.
https://hal-univ-artois.archives-ouvertes.fr/hal-00528128
Contributor : Wilfried Déplanques Connect in order to contact the contributor
Submitted on : Thursday, October 21, 2010 - 9:38:04 AM
Last modification on : Friday, January 21, 2022 - 3:27:37 AM
Contributor : Wilfried Déplanques Connect in order to contact the contributor
Submitted on : Thursday, October 21, 2010 - 9:38:04 AM
Last modification on : Friday, January 21, 2022 - 3:27:37 AM