Accumulation of Golgi-processed secretory proteins in an organelle of high density upon reduction of ATP concentration in rat hepatocytes

We have previously shown that when rat hepatocytes are incubated with 4 mM azide, which reduces the intracellular ATP concentration to about 30% of its normal level, secretory proteins are reversibly arrested within the cell. Analysis of haptoglobin after 150 min of azide incubation shows that its c...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 1992-02, Vol.267 (4), p.2760-2766
Main Authors: Persson, R, Schnell, C R, Borg, L A, Fries, E
Format: Article
Language:English
Subjects:
Adenosine Triphosphate - metabolism
Albumins - metabolism
Animals
ATP
Azides - metabolism
Biological and medical sciences
Carbohydrate Metabolism
Carbohydrate Sequence
Cell physiology
Cells, Cultured
Electrophoresis, Polyacrylamide Gel
Endoplasmic Reticulum - metabolism
Endoplasmic Reticulum - ultrastructure
Fundamental and applied biological sciences. Psychology
Golgi apparatus
Golgi Apparatus - metabolism
Golgi Apparatus - ultrastructure
Haptoglobins - metabolism
Immunohistochemistry
Liver - metabolism
Liver - ultrastructure
Membrane and intracellular transports
Microscopy, Immunoelectron
Molecular and cellular biology
Molecular Sequence Data
Organelles - metabolism
Organelles - ultrastructure
Precipitin Tests
Rats
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We have previously shown that when rat hepatocytes are incubated with 4 mM azide, which reduces the intracellular ATP concentration to about 30% of its normal level, secretory proteins are reversibly arrested within the cell. Analysis of haptoglobin after 150 min of azide incubation shows that its carbohydrates have been processed by Golgi enzymes (Persson, R., Ahlström, E., and Fries, E. (1988) J. Cell Biol. 107, 2503-2510). Here, we have further characterized the site of arrest. Subcellular fractionation by density gradient centrifugation showed that albumin and haptoglobin fractionated like a marker for the endoplasmic reticulum. Localization of albumin by immunoelectron microscopy showed, however, that it occurred in flattened cisternae and that the endoplasmic reticulum was devoid of the protein. A possible explanation for these results is that the azide treatment blocks transport through the Golgi complex, leading to an accumulation of secretory proteins in a pre- or early Golgi compartment of high density. This compartment could contain sufficient amounts of Golgi enzymes to carry out the observed carbohydrate processing upon prolonged incubation or possibly acquire them as an effect of the azide treatment.
ISSN:0021-9258
1083-351X
DOI:10.1016/S0021-9258(18)45944-3