Publications by authors named "Roxanne Sheffield"

Studies in continuously cultured cells have established that familial Alzheimer's disease (FAD) mutant presenilin 1 (PS1) delays exit of the amyloid precursor protein (APP) from the trans-Golgi network (TGN). Here we report the first description of PS1-regulated APP trafficking in cerebral neurons in culture and in vivo. Using neurons from transgenic mice or a cell-free APP transport vesicle biogenesis system derived from the TGN of those neurons, we demonstrated that knocking-in an FAD-associated mutant PS1 transgene was associated with delayed kinetics of APP arrival at the cell surface.

View Article and Find Full Text PDF

Gender differences exist in the development of the nigrostriatal dopamine system, and in the incidence and course of pediatric and adult neuropsychiatric diseases in which this system is implicated. The medium size spiny neuron (MSN) is the major output neuron of the caudate nucleus. It receives a large dopaminergic input from the substantia nigra, and 96% of the MSNs express DARPP-32, a dopamine and cyclic AMP-regulated phosphoprotein and key mediator of dopamine function.

View Article and Find Full Text PDF

Aim: In Alzheimer's disease (AD) it is well known that specific regions of the brain are particularly vulnerable to the pathologic insults of the disease. In particular, the hippocampus is affected very early in the disease and by end stage AD is ravaged by neurofibrillary tangles and senile plaques (i.e.

View Article and Find Full Text PDF