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Polarization of endocytosis and receptor topography on cultured macrophages

In the 1774.2 macrophage cell line, microtubule disassembly by colchicine causes the polarization of membrane functions ane structure. Colchicine-treated cells develop a bulge or protuberance that is bordered by microvillous membrane. The protuberance is the site of concanavalin A cap formation. The...

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Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1980
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Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2110654/
https://www.ncbi.nlm.nih.gov/pubmed/7419574
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description In the 1774.2 macrophage cell line, microtubule disassembly by colchicine causes the polarization of membrane functions ane structure. Colchicine-treated cells develop a bulge or protuberance that is bordered by microvillous membrane. The protuberance is the site of concanavalin A cap formation. The fluid pinocytosis of horseradish peroxidase and of fluorescein- and rhodamine-conjugated high molecular- weight dextrans, the adsorptive pinocytosis of concanavalin A, and the concentration and phagocytosis at 37 degrees C of a range of phagocytic particles (IgG- and complement-opsonized erythrocytes, complement- opsonized zymosan, latex shpres, albumin-stabilized oil droplets) are all similarly restricted to the protuberance. A reduction in the rate of dextran pinocytosis, determined by fluorimetry, and reductions in phagocytic rates for oil emulsion and IgG-opsonized erythrocytes accompany the polarization of endocytic activity in colchicine-trated 1774.2 macrophages. Membrane receptors for phagocytic particles are not confined to the protuberance but rather may display their own unique topographical asymmetry. The inherent topography of receptors was inferred from particle distribution under conditions that limit particle-receptor redistribution (after labeling at 4 degrees C or a very brief incubation at 37 degrees C). Under these restrictive conditions, latex binding sites were detected over the whole membrane whereas receptors for IgG-opsonized erythrocytes, aggregated IgG, complement-opsonized erythrocytes, and complement-opsonized zymosan were excluded from the protuberance. Thus, functional (endocytosis) and structural (inherent receptor distribution) analyses of membrane topography define different patterns of asymmetry in protuberant cells. The asymmetry induced in 1774.2 macrophages by colchicine is highly analogous to the functional and structural polarity of epithelial cells. Exploration of this analogy may provide insight into the development of polarized epithelia and, more generally, into mechanisms by which specialized areas of membrane are established.
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spelling pubmed-21106542008-05-01 Polarization of endocytosis and receptor topography on cultured macrophages J Cell Biol Articles In the 1774.2 macrophage cell line, microtubule disassembly by colchicine causes the polarization of membrane functions ane structure. Colchicine-treated cells develop a bulge or protuberance that is bordered by microvillous membrane. The protuberance is the site of concanavalin A cap formation. The fluid pinocytosis of horseradish peroxidase and of fluorescein- and rhodamine-conjugated high molecular- weight dextrans, the adsorptive pinocytosis of concanavalin A, and the concentration and phagocytosis at 37 degrees C of a range of phagocytic particles (IgG- and complement-opsonized erythrocytes, complement- opsonized zymosan, latex shpres, albumin-stabilized oil droplets) are all similarly restricted to the protuberance. A reduction in the rate of dextran pinocytosis, determined by fluorimetry, and reductions in phagocytic rates for oil emulsion and IgG-opsonized erythrocytes accompany the polarization of endocytic activity in colchicine-trated 1774.2 macrophages. Membrane receptors for phagocytic particles are not confined to the protuberance but rather may display their own unique topographical asymmetry. The inherent topography of receptors was inferred from particle distribution under conditions that limit particle-receptor redistribution (after labeling at 4 degrees C or a very brief incubation at 37 degrees C). Under these restrictive conditions, latex binding sites were detected over the whole membrane whereas receptors for IgG-opsonized erythrocytes, aggregated IgG, complement-opsonized erythrocytes, and complement-opsonized zymosan were excluded from the protuberance. Thus, functional (endocytosis) and structural (inherent receptor distribution) analyses of membrane topography define different patterns of asymmetry in protuberant cells. The asymmetry induced in 1774.2 macrophages by colchicine is highly analogous to the functional and structural polarity of epithelial cells. Exploration of this analogy may provide insight into the development of polarized epithelia and, more generally, into mechanisms by which specialized areas of membrane are established. The Rockefeller University Press 1980-07-01 /pmc/articles/PMC2110654/ /pubmed/7419574 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
Polarization of endocytosis and receptor topography on cultured macrophages
title Polarization of endocytosis and receptor topography on cultured macrophages
title_full Polarization of endocytosis and receptor topography on cultured macrophages
title_fullStr Polarization of endocytosis and receptor topography on cultured macrophages
title_full_unstemmed Polarization of endocytosis and receptor topography on cultured macrophages
title_short Polarization of endocytosis and receptor topography on cultured macrophages
title_sort polarization of endocytosis and receptor topography on cultured macrophages
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2110654/
https://www.ncbi.nlm.nih.gov/pubmed/7419574