Elucidating the molecular mechanisms by which the Alzheimer's disease amyloid precursor protein regulates cellular copper efflux in the aging brain
Supervisor: Dr Ed Parkin
Copper, whilst essential to life, is potentially cytotoxic and levels are elevated in the aged brain giving rise to the possibility of neuronal damage. Molecular mechanisms are, therefore, required for the precise regulation of cellular copper content. The amyloid precursor protein (APP) is a type 1 membrane protein which contains a high affinity copper binding ectodomain which can be proteolytically released or 'shed' from the cell surface. Various studies have implicated APP as a regulator of cellular copper efflux.In the current proposal we intend to elucidate the molecular mechanisms through which APP regulates cellular copper. We will express APP constructs which are deficient in copper binding and/or proteolytic ectodomain shedding (both the copper binding residues and the proteolytic sites within APP have been characterised previously) in the human neouroblastoma cell line, SH-SY5Y. Changes in cellular copper content will be monitored by inductively coupled plasma mass spectroscopy (ICP-MS). The effect of the APP constructs on the expression/activity/subcellular localisation of a range of known copper transport proteins (e.g. hCtr1, ATP7A, Cox17, Atx1, SOD1) will also be investigated.