Amyloid-β(1-42) Aggregation Initiates Its Cellular Uptake and Cytotoxicity
Autor: | Simon Prisner, Andreas Herrmann, Eva Illes-Toth, Niraja Kedia, Erich E. Wanker, Ivan Haralampiev, Sha Jin, Jan Bieschke |
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Rok vydání: | 2015 |
Předmět: |
0301 basic medicine
Amyloid media_common.quotation_subject Endocytic cycle Protein aggregation Endocytosis Biochemistry Protein Aggregation Pathological Protein Structure Secondary Cell Line Cell membrane 03 medical and health sciences Alzheimer Disease mental disorders medicine Extracellular Humans Internalization Molecular Biology media_common Amyloid beta-Peptides Chemistry Cell Membrane Molecular Bases of Disease Cell Biology Peptide Fragments Protein Transport 030104 developmental biology medicine.anatomical_structure Endocytic vesicle Biophysics Function and Dysfunction of the Nervous System |
Zdroj: | The Journal of biological chemistry. 291(37) |
ISSN: | 1083-351X |
Popis: | The accumulation of amyloid beta peptide(1-42) (Abeta(1-42)) in extracellular plaques is one of the pathological hallmarks of Alzheimer disease (AD). Several studies have suggested that cellular reuptake of Abeta(1-42) may be a crucial step in its cytotoxicity, but the uptake mechanism is not yet understood. Abeta may be present in an aggregated form prior to cellular uptake. Alternatively, monomeric peptide may enter the endocytic pathway and conditions in the endocytic compartments may induce the aggregation process. Our study aims to answer the question whether aggregate formation is a prerequisite or a consequence of Abeta endocytosis. We visualized aggregate formation of fluorescently labeled Abeta(1-42) and tracked its internalization by human neuroblastoma cells and neurons. beta-Sheet-rich Abeta(1-42) aggregates entered the cells at low nanomolar concentration of Abeta(1-42). In contrast, monomer uptake faced a concentration threshold and occurred only at concentrations and time scales that allowed Abeta(1-42) aggregates to form. By uncoupling membrane binding from internalization, we found that Abeta(1-42) monomers bound rapidly to the plasma membrane and formed aggregates there. These structures were subsequently taken up and accumulated in endocytic vesicles. This process correlated with metabolic inhibition. Our data therefore imply that the formation of beta-sheet-rich aggregates is a prerequisite for Abeta(1-42) uptake and cytotoxicity. |
Databáze: | OpenAIRE |
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