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Studying Membrane Protein Trafficking in Drosophila Photoreceptor Cells Using eGFP-Tagged Proteins
Published on: January 21, 2022
Trafficking, turnover and membrane topology of PrP
1Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
Abstract:
Cell biological studies of PrP have contributed enormously to our understanding of prion diseases. Like other membrane proteins, PrP(C) is post-translationally processed in the endoplasmic reticulum and Golgi on its way to the cell surface after synthesis. Cell surface PrP(C) constitutively cycles between the plasma membrane and early endosomes via a clathrin-dependent mechanism, a pathway consistent with a suggested role for PrP(C) in cellular trafficking of copper ions. PrP molecules carrying mutations linked to inherited prion diseases display several abnormalities in their biochemical properties, maturation, and localisation that may explain their pathogenicity. Recent results have clarified the role of the proteasome in degradation of PrP, and the properties of a transmembrane form of PrP which may play a neurotoxic role in prion diseases.
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