Presenilin-mediated cleavage of APP regulates synaptotagmin-7 and presynaptic plasticity

• Published in: Nature communications Vol. 9; no. 1; pp. 4780 - 14
• Main Authors: Barthet, Gaël, Jordà-Siquier, Tomàs, Rumi-Masante, Julie, Bernadou, Fanny, Müller, Ulrike, Mulle, Christophe
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14-11-2018; Nature Publishing Group; Nature Portfolio
• Subjects: 14; 14/19; 42; 42/41; 631/378/1689/1283; 631/378/2591/2594; 64; 64/110; 82/51; 9/74; Age; Alzheimer Disease - genetics; Alzheimer Disease - metabolism; Alzheimer's disease; Amyloid beta-Protein Precursor - metabolism; Amyloid precursor protein; Amyloid Precursor Protein Secretases - antagonists & inhibitors; Amyloid Precursor Protein Secretases - genetics; Amyloid Precursor Protein Secretases - metabolism; Animals; Brain - metabolism; CA3 Region, Hippocampal - metabolism; Calcium; Calcium ions; Cleavage; Genes; Humanities and Social Sciences; Life Sciences; Mice; Mice, Knockout; multidisciplinary; Mutation; Neurodegenerative diseases; Neuronal Plasticity - genetics; Neurons and Cognition; Neurotransmitter release; Patch-Clamp Techniques; Pharmacology; Post-transcription; Presenilin; Presenilin 1; Presenilin-1 - genetics; Presenilin-2 - genetics; Presynaptic plasticity; Proteins; Proteolysis; Replenishment; Science; Science (multidisciplinary); Secretase; Substrates; Synaptic Transmission; Synaptic vesicles; Synaptotagmin; Synaptotagmins - metabolism
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-018-06813-x

Mutations of the intramembrane protease presenilin (PS) or of its main substrate, the amyloid precursor protein (APP), cause early-onset form of Alzheimer disease. PS and APP interact with proteins of the neurotransmitter release machinery without identified functional consequences. Here we report that genetic deletion of PS markedly decreases the presynaptic levels of the Ca
2+
sensor synaptotagmin-7 (Syt7) leading to impaired synaptic facilitation and replenishment of synaptic vesicles. The regulation of Syt7 expression by PS occurs post-transcriptionally and depends on γ-secretase proteolytic activity. It requires the substrate APP as revealed by the combined genetic invalidation of APP and PS1, and in particular the APP-Cterminal fragments which interact with Syt7 and accumulate in synaptic terminals under pharmacological or genetic inhibition of γ-secretase. Thus, we uncover a role of PS in presynaptic mechanisms, through APP cleavage and regulation of Syt7, that highlights aberrant synaptic vesicle processing as a possible new pathway in AD.
Mutations in presenilin, which cleaves amyloid precursor protein, cause familial Alzheimer’s Disease. Here, the authors show that loss of presenilin leads to loss of synaptotagmin 7, leading to impaired presynaptic release.