title: Fluorimetric analysis of copper transport mechanisms in the b104 neuroblastoma cell model: a contribution from cellular prion protein to copper supplying.
abstract: Dysregulated body copper homeostasis can negatively impact neuronal functions, but full knowledge of the mechanisms underlying the cell metal distribution has not been achieved yet. The high-affinity copper transporter 1 (Ctr1) is considered the main route for cell copper entry, while the cellular prion protein (PrP(C)) is presumed to be involved in the same process. Anchored to the outer side of the plasma membrane, this protein has the ability to bind copper ions and undergo internalization. To provide indications about the contribution of Ctr1 and PrP(C) proteins in cell copper transport, we used a fluorimetric method to characterize the kinetic properties of ion internalization in a neuroblastoma cell model, overexpressing prion protein (B104). Biochemical characteristics of intake delineated in the presence of other metal ions and an excess of extracellular potassium were compatible with PrP(C)-mediated endocytotic transport. Accordingly, inhibition of clathrin-dependent endocytosis by hypertonic shock and enzymatic removal of surface prion protein reduced copper influx by the same extent. On the whole, experimental evidence collected in a neuron-like cell model sustains a role for PrP(C) in mediating copper uptake by clathrin-dependent endocytosis.
authors: Department of Biological and Environmental Science and Technology, University of Salento, Lecce, Italy.
authors: Emanuela
authors: E
authors: Urso
authors: Antonia
authors: A
authors: Rizzello
authors: Raffaele
authors: R
authors: Acierno
authors: Maria Giulia
authors: MG
authors: Lionetto
authors: Benedetto
authors: B
authors: Salvato
authors: Carlo
authors: C
authors: Storelli
authors: Michele
authors: M
authors: Maffia
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000502:physiology; D045744:Cell Line, Tumor; D003300:Copper / Q000378:metabolism*; D005470:Fluorometry / Q000379:methods*; D007700:Kinetics; D018613:Microscopy, Confocal; D008962:Models, Theoretical; D009447:Neuroblastoma / Q000378:metabolism*; D011328:Prions / Q000378:metabolism*; D011485:Protein Binding; D051381:Rats
chemical_list: D011328:Prions; D003300:Copper