Title: Carrier-mediated transport of intact UDP-glucuronic acid into the lumen of endoplasmic-reticulum-derived vesicles from rat liver
Authors: Bossuyt, Xavier ×
Blanckaert, Norbert #
Issue Date: Aug-1994
Series Title: The Biochemical journal vol:302 ( Pt 1) pages:261-9
Abstract: Uptake and metabolism of UDP-glucuronic acid (UDPGlcA) by rough-endoplasmic-reticulum (RER)-derived vesicles was studied. Analysis of the molecular species, double-labelling experiments and trans-stimulation experiments revealed that initial uptake represented entry into microsomes of predominantly intact UDPGlcA, concomitant with rapid hydrolysis of the internalized nucleotide sugar. The uptake constituted effective translocation from the medium into the lumen of the vesicles. Thus the amount of vesicle-associated label at equilibrium uptake was directly proportional to the volume of the intravesicular space. Permeabilized microsomes were unable to retain UDPGlcA. The microsomal uptake of UDPGlcA met the criteria of bidirectional carrier-mediated translocation. Transport was time- and temperature-dependent, saturable, selective, capable of trans-stimulation, and operational against a concentration gradient. Microsomal uptake was inhibited by N-ethylmaleimide that was presented at the cytosolic side of the endoplasmic-reticulum (ER) membrane. Uptake studies performed in membrane preparations that were highly enriched in RER, smooth ER or Golgi revealed that UDPGlcA was taken up by the ER as well as by the Golgi apparatus. Our findings demonstrate the existence in rat liver ER of a carrier system mediating proper translocation of intact UDPGlcA across the membrane.
ISSN: 0264-6021
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Laboratory of Clinical Bacteriology and Mycology
Experimental Laboratory Immunology
Department of Imaging & Pathology - miscellaneous
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science