Isolation and characterization of a highly enriched preparation of receptosomes (endosomes) from a human cell line.
- 1 September 1983
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 80 (17) , 5335-5339
- https://doi.org/10.1073/pnas.80.17.5335
Abstract
Receptor-mediated endocytosis proceeds by transfer of receptor-ligand complexes from clathrin-coated pits at the cell surface to uncoated endocytic vesicles termed receptosomes (or endosomes). These vesicles were now purified > 37-fold based on their content of newly internalized epidermal growth factor. 125I-labeled EGF [epidermal growth factor] was bound to human KB carcinoma cells at 4.degree. C, and then the cells were warmed to 37.degree. C for 8 min and disrupted. The purification scheme involved density gradient centrifugation on colloidal silica, and sucrose and gel filtration on Sephacryl S-1000. Relative to homogenate, receptosomes are enriched 4.3-fold in their cholesterol content and depleted in enzyme markers for plasma membranes (2- to 3-fold) and lysosomes (9-fold). Receptosomes have a polypeptide composition that is different from plasma membrane, lysosome and other homogenate fractions. They are enriched in transferrin receptors (30-fold) and in unidentified MW 70,000-75,000 glycoprotein(s); they contain phosphomannosyl receptors. They do not contain detectable amounts of clathrin.Keywords
This publication has 30 references indexed in Scilit:
- Ultrastructural immunocytochemical localization of the phosphomannosyl receptor in Chinese hamster ovary (CHO) cells.Journal of Histochemistry & Cytochemistry, 1983
- The internal reticular apparatus of Camillo Golgi: a complex, heterogeneous organelle, enriched in acid, neutral, and alkaline phosphatases, and involved in glycosylation, secretion, membrane flow, lysosome formation, and intracellular digestion.Journal of Histochemistry & Cytochemistry, 1982
- Transit of epidermal growth factor through coated pits of the Golgi system.The Journal of cell biology, 1982
- Journey to the Center of the Cell: Role of the ReceptosomeScience, 1981
- Receptor-mediated endocytosis in cultured fibroblasts: cryptic coated pits and the formation of receptosomes.Journal of Histochemistry & Cytochemistry, 1981
- alpha 2-macroglobulin adsorbed to colloidal gold: a new probe in the study of receptor-mediated endocytosis.The Journal of cell biology, 1981
- Purification and characterization of human lysosomes from EB-virus transformed lymphoblastsExperimental Cell Research, 1981
- Coated pits, coated vesicles, and receptor-mediated endocytosisNature, 1979
- Lack of correlation between the decreased expression of cell surface LETS protein and tumorigenicity in human cell hybridsCell, 1978
- Phospholipid class and fatty acid composition of Golgi apparatus isolated from rat liver and comparison with other cell fractionsBiochemistry, 1970