Distinct role of clathrin-mediated endocytosis in the functional uptake of cholera toxin
Autor: | Albert R. Lagrou, Marc J.S. De Wolf, Davy Vanden Broeck |
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Jazyk: | angličtina |
Rok vydání: | 2007 |
Předmět: |
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media_common.quotation_subject Endocytic cycle clathrin-mediated endocytosis Endocytosis medicine.disease_cause Clathrin General Biochemistry Genetics and Molecular Biology CAVEOLAE medicine COATED PIT FORMATION TRAFFICKING Internalization chlorpromazine Biology media_common MICRODOMAINS biology cholera toxin CHOLESTEROL Cholera toxin Biology and Life Sciences Receptor-mediated endocytosis CYCLODEXTRIN Cell biology internalization Chemistry Cell culture siRNA PLASMA-MEMBRANE biology.protein DEPLETION Intracellular |
Zdroj: | Acta biochimica Polonica ACTA BIOCHIMICA POLONICA |
ISSN: | 0001-527X |
Popis: | The involvement of the clathrin-mediated endocytic internalization route in the uptake of cholera toxin (CT) was investigated using different cell lines, including the human intestinal Caco-2 and T84 cell lines, green monkey Vero cells, SH-SY5Y neuroblastoma cells and Madin-Darby canine kidney cells. Suppression of the clathrin-mediated endocytic pathway by classical biochemical procedures, like intracellular acidification and potassium depletion, inhibited cholera toxin uptake by up to about 50% as well as its ability to raise intracellular levels of cAMP. Also prior exposure of these cell types to the cationic amphiphilic drug chlorpromazine reduced the functional uptake of cholera toxin, even to a greater extent. These effects were dose- and cell type-dependent, suggesting an involvement of clathrin-mediated endocytosis in the functional uptake of cholera toxin. For a more straightforward approach to study the role of the clathrin-mediated uptake in the internalization of cholera toxin, a Caco-2(eps-) cell line was exploited. These Caco-2(eps-) cells constitutively suppress the expression of epsin, an essential accessory protein of clathrin-mediated endocytosis, thereby selectively blocking this internalization route. CT uptake was found to be reduced by over 60% in Caco-2(eps-) paralleled by a diminished ability of CT to raise the level of cAMP. The data presented suggest that the clathrin-mediated uptake route fulfils an important role in the functional internalization of cholera toxin in several cell types. |
Databáze: | OpenAIRE |
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