Interaction of reelin with amyloid precursor protein promotes neurite outgrowth.
The processing of amyloid precursor protein (APP) to Abeta is an important event in the pathogenesis of Alzheimer's disease, but the physiological function of APP is not well understood. Our previous work has shown that APP processing and Abeta production are regulated by the extracellular matrix protein Reelin. In the ... present study, we examined whether Reelin interacts with APP, and the functional consequences of that interaction in vitro. Using coimmunoprecipitation, we found that Reelin interacted with APP through the central domain of Reelin (repeats 3-6) and the E1 extracellular domain of APP. Reelin increased cell surface levels of APP and decreased endocytosis of APP in hippocampal neurons in vitro. In vivo, Reelin levels were increased in brains of APP knock-out mice and decreased in APP-overexpressing mice. RNA interference knockdown of APP decreased neurite outgrowth in vitro and prevented Reelin from increasing neurite outgrowth. Knock-out of APP or Reelin decreased dendritic arborization in cortical neurons in vivo, and APP overexpression increased dendritic arborization. APP and Reelin have previously been shown to promote neurite outgrowth through interactions with integrins. We confirmed that APP interacted with alpha3beta1 integrin, and alpha3beta1 integrin altered APP trafficking and processing. Addition of an alpha3beta1 integrin antibody prevented APP and Reelin-induced neurite outgrowth. These findings demonstrate that Reelin interacts with APP, potentially having important effects on neurite development.
Mesh Terms:
Amyloid beta-Protein Precursor, Animals, Brain, COS Cells, Cell Adhesion Molecules, Neuronal, Cell Line, Tumor, Cells, Cultured, Chlorocebus aethiops, Dendrites, Extracellular Matrix Proteins, Humans, Integrin alpha3beta1, Integrin beta1, Mice, Mice, Inbred C57BL, Mice, Knockout, Mice, Neurologic Mutants, Mice, Transgenic, Nerve Tissue Proteins, Neurites, Protease Nexins, Rats, Rats, Sprague-Dawley, Receptors, Cell Surface, Serine Endopeptidases
Amyloid beta-Protein Precursor, Animals, Brain, COS Cells, Cell Adhesion Molecules, Neuronal, Cell Line, Tumor, Cells, Cultured, Chlorocebus aethiops, Dendrites, Extracellular Matrix Proteins, Humans, Integrin alpha3beta1, Integrin beta1, Mice, Mice, Inbred C57BL, Mice, Knockout, Mice, Neurologic Mutants, Mice, Transgenic, Nerve Tissue Proteins, Neurites, Protease Nexins, Rats, Rats, Sprague-Dawley, Receptors, Cell Surface, Serine Endopeptidases
J. Neurosci.
Date: Jun. 10, 2009
PubMed ID: 19515914
View in: Pubmed Google Scholar
Download Curated Data For This Publication
223011
Switch View:
- Interactions 4