Role of genes linked to sporadic Alzheimer's disease risk in the production of &#x3b2;-amyloid peptides.

Jitin Bali; Ali Hashemi Gheinani; Sebastian Zurbriggen; Lawrence Rajendran

doi:10.1073/pnas.1201632109

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Role of genes linked to sporadic Alzheimer's disease risk in the production of β-amyloid peptides.

Jitin Bali·Ali Hashemi Gheinani·Sebastian Zurbriggen·Lawrence Rajendran

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Abstract

Alzheimer's disease (AD) is characterized by the presence of toxic protein aggregates or plaques composed of the amyloid β (Aβ) peptide. Various lengths of Aβ peptide are generated by proteolytic cleavages of the amyloid precursor protein (APP). Mutations in many familial AD-associated genes affect the production of the longer Aβ42 variant that preferentially accumulates in plaques. In the case of sporadic or late-onset AD, which accounts for greater than 95% of cases, several genes are implicated in increasing the risk, but whether they also cause the disease by altering amyloid levels is currently unknown. Through loss of function studies in a model cell line, here RNAi-mediated silencing of several late onset AD genes affected Aβ levels is shown. However, unlike the genes underlying familial AD, late onset AD-susceptibility genes do not specifically alter the Aβ42/40 ratios and suggest that these genes probably contribute to AD through distinct mechanisms.

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Jitin Bali, Ali Hashemi Gheinani, Sebastian Zurbriggen, Lawrence Rajendran. 2012-09-04. Role of genes linked to sporadic Alzheimer's disease risk in the production of β-amyloid peptides.. https://doi.org/10.1073/pnas.1201632109

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