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Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes
The intra- and transcellular transports of hepatic secretory and membrane proteins were studied in rats in vivo using [3H]fucose and [35S]cysteine as metabolic precursors. Incorporated radioactivity in plasma, bile, and liver subcellular fractions was measured and the labeled proteins of the Golgi c...
Formato: | Texto |
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Lenguaje: | English |
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The Rockefeller University Press
1983
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2112675/ https://www.ncbi.nlm.nih.gov/pubmed/6630294 |
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collection | PubMed |
description | The intra- and transcellular transports of hepatic secretory and membrane proteins were studied in rats in vivo using [3H]fucose and [35S]cysteine as metabolic precursors. Incorporated radioactivity in plasma, bile, and liver subcellular fractions was measured and the labeled proteins of the Golgi complex, bile, and plasma were separated by SDS PAGE and identified by fluorography. 3H-radioactivity in Golgi fractions peaked at 10 min postinjection (p.i.) and then declined concomitantly with the appearance of labeled glycoproteins in plasma. Maximal secretion of secretory fucoproteins from Golgi occurred between 10 and 20 min p.i. In contrast, the clearance of labeled proteins from Golgi membrane subfractions occurred past 30 min p.i., indicating that membrane proteins leave the Golgi complex at least 30 min later than the bulk of content proteins. A major 80,000-dalton form of secretory component (SC) was identified in the bile by co-precipitation with (IgA)2 by an anti-IgA antibody. An antibody (raised in rabbit) against the biliary 80,000-dalton peptide recognized two larger forms (116,000 and 94,000 dalton), presumably precursors, in Golgi membranes. A comparative study of kinetics of transport of 35S-SC and 35S-albumin showed that albumin peaked in bile at approximately 45 min p.i., whereas the SC peak occurred at 80 min p.i., suggesting that the transit time differs for plasma and membrane proteins that are delivered to the bile canaliculus. |
format | Text |
id | pubmed-2112675 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1983 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21126752008-05-01 Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes J Cell Biol Articles The intra- and transcellular transports of hepatic secretory and membrane proteins were studied in rats in vivo using [3H]fucose and [35S]cysteine as metabolic precursors. Incorporated radioactivity in plasma, bile, and liver subcellular fractions was measured and the labeled proteins of the Golgi complex, bile, and plasma were separated by SDS PAGE and identified by fluorography. 3H-radioactivity in Golgi fractions peaked at 10 min postinjection (p.i.) and then declined concomitantly with the appearance of labeled glycoproteins in plasma. Maximal secretion of secretory fucoproteins from Golgi occurred between 10 and 20 min p.i. In contrast, the clearance of labeled proteins from Golgi membrane subfractions occurred past 30 min p.i., indicating that membrane proteins leave the Golgi complex at least 30 min later than the bulk of content proteins. A major 80,000-dalton form of secretory component (SC) was identified in the bile by co-precipitation with (IgA)2 by an anti-IgA antibody. An antibody (raised in rabbit) against the biliary 80,000-dalton peptide recognized two larger forms (116,000 and 94,000 dalton), presumably precursors, in Golgi membranes. A comparative study of kinetics of transport of 35S-SC and 35S-albumin showed that albumin peaked in bile at approximately 45 min p.i., whereas the SC peak occurred at 80 min p.i., suggesting that the transit time differs for plasma and membrane proteins that are delivered to the bile canaliculus. The Rockefeller University Press 1983-11-01 /pmc/articles/PMC2112675/ /pubmed/6630294 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Articles Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
title | Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
title_full | Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
title_fullStr | Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
title_full_unstemmed | Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
title_short | Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
title_sort | intracellular and transcellular transport of secretory component and albumin in rat hepatocytes |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2112675/ https://www.ncbi.nlm.nih.gov/pubmed/6630294 |