期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2002
卷号：99
期号：10
页码：7102-7107
DOI：10.1073/pnas.102192599
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The {beta}-amyloid precursor protein (APP) and the Notch receptor undergo intramembranous proteolysis by the Presenilin-dependent {gamma}-secretase. The cleavage of APP by {gamma}-secretase releases amyloid-{beta} peptides, which have been implicated in the pathogenesis of Alzheimer's disease, and the APP intracellular domain (AID), for which the function is not yet well understood. A similar {gamma}-secretase-mediated cleavage of the Notch receptor liberates the Notch intracellular domain (NICD). NICD translocates to the nucleus and activates the transcription of genes that regulate the generation, differentiation, and survival of neuronal cells. Hence, some of the effects of APP signaling and Alzheimer's disease pathology may be mediated by the interaction of APP and Notch. Here, we show that membrane-tethered APP binds to the cytosolic Notch inhibitors Numb and Numb-like in mouse brain lysates. AID also binds Numb and Numb-like, and represses Notch activity when released by APP. Thus, {gamma}-secretase may have opposing effects on Notch signaling; positive by cleaving Notch and generating NICD, and negative by processing APP and generating AID, which inhibits the function of NICD.
