Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes
We have followed the transfer of EGF-EGF receptor (EGFR) complexes from endosomal vacuoles that contain transferrin receptors (TfR) to lysosome vacuoles identified by their content of HRP loaded as a 15-min pulse 4 h previously. We show that the HRP-loaded lysosomes are lysosomal- associated membran...
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Lenguaje: | English |
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The Rockefeller University Press
1996
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2120766/ https://www.ncbi.nlm.nih.gov/pubmed/8601581 |
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collection | PubMed |
description | We have followed the transfer of EGF-EGF receptor (EGFR) complexes from endosomal vacuoles that contain transferrin receptors (TfR) to lysosome vacuoles identified by their content of HRP loaded as a 15-min pulse 4 h previously. We show that the HRP-loaded lysosomes are lysosomal- associated membrane protein-1 (LAMP-1) positive, mannose-6-phosphate receptor (M6PR) negative. and contain active acid hydrolase. EGF-EGFR complexes are delivered to these lysosomes intact and are then rapidly degraded. Preactivating the HRP contained within the preloaded lysosomes inhibits the delivery of EGFR and degradation of EGF, and results in the accumulation of EGFR-containing multivesicular bodies (MVB). With time these accumulating MVB undergo a series of maturation changes that include the loss of TfR, the continued recruitment of EGFR, and the accumulation of internal vesicles, but they remain LAMP-1 and M6PR negative. The mature MVB are often seen to make direct contact with lysosomes containing preactivated HRP, but their perimeter membranes remain intact. Together our observations suggest that the transfer of EGF-EGFR complexes from the TfR-containing endosome compartment to the lysosomes that degrade them employs a single vacuolar intermediate, the maturing MVB, and can be achieved by a single heterotypic fusion step. |
format | Text |
id | pubmed-2120766 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1996 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21207662008-05-01 Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes J Cell Biol Articles We have followed the transfer of EGF-EGF receptor (EGFR) complexes from endosomal vacuoles that contain transferrin receptors (TfR) to lysosome vacuoles identified by their content of HRP loaded as a 15-min pulse 4 h previously. We show that the HRP-loaded lysosomes are lysosomal- associated membrane protein-1 (LAMP-1) positive, mannose-6-phosphate receptor (M6PR) negative. and contain active acid hydrolase. EGF-EGFR complexes are delivered to these lysosomes intact and are then rapidly degraded. Preactivating the HRP contained within the preloaded lysosomes inhibits the delivery of EGFR and degradation of EGF, and results in the accumulation of EGFR-containing multivesicular bodies (MVB). With time these accumulating MVB undergo a series of maturation changes that include the loss of TfR, the continued recruitment of EGFR, and the accumulation of internal vesicles, but they remain LAMP-1 and M6PR negative. The mature MVB are often seen to make direct contact with lysosomes containing preactivated HRP, but their perimeter membranes remain intact. Together our observations suggest that the transfer of EGF-EGFR complexes from the TfR-containing endosome compartment to the lysosomes that degrade them employs a single vacuolar intermediate, the maturing MVB, and can be achieved by a single heterotypic fusion step. The Rockefeller University Press 1996-03-02 /pmc/articles/PMC2120766/ /pubmed/8601581 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 Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes |
title | Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes |
title_full | Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes |
title_fullStr | Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes |
title_full_unstemmed | Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes |
title_short | Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes |
title_sort | multivesicular endosomes containing internalized egf-egf receptor complexes mature and then fuse directly with lysosomes |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2120766/ https://www.ncbi.nlm.nih.gov/pubmed/8601581 |