Familial Alzheimer's disease-linked presenilin mutants and intracellular Ca2+ handling: A single-organelle, FRET-based analysis. (May 2019)

• Record Type: Journal Article
• Authors: Greotti, Elisa; Capitanio, Paola; Wong, Andrea; Pozzan, Tullio; Pizzo, Paola; Pendin, Diana
• Is Part Of: Cell calcium. Volume 79(2019)
• Page Start: 44
• Page End: 56
• Publication Date: 2019-05
• Subjects: AD Alzheimer's disease -- Aβ β-amyloid -- APP amyloid precursor protein -- ATP adenosine trisphosphate -- BK bradykinin -- [Ca2+] Ca2+ concentration -- CPA cyclopiazonic acid -- cpV circularly permuted Venus -- DAPT N-[N-(3, 5-Difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester -- DKO double knock-out -- ECFP Enhanced Cyan Fluorescent Protein -- ER Endoplasmic Reticulum -- FAD Familial Alzheimer's disease -- FCS Fetal Calf Serum -- FRET Fluorescence/Förster Resonance Energy Transfer -- GA Golgi apparatus -- IP3Rs inositol trisphosphate receptors -- KO Knock-Out -- MAMs mitochondrial-associated membranes -- MEFs Mouse Embryonic Fibroblasts -- mGluRs metabotropic glutamate receptors -- PM plasma membrane -- PS Presenilin -- R ratio -- REST Repressor Element 1-Silencing Transcription factor -- RyRs Ryanodine Receptors -- SAD Sporadic Alzheimer's Disease -- SOCE Store-Operated Ca2+ Entry -- SERCA Sarco/Endoplasmic Reticulum Ca2+-ATPase -- SPCA1 Secretory Pathway Ca2+ ATPase1 -- STIM1 STromal Interaction Molecule 1 -- STIM2 STromal Interaction Molecule 2 -- VOCCs Voltage-operated Ca2+ channels; Ca2+ stores -- Presenilin -- Alzheimer's disease -- SERCA -- FRET-based Ca2+probe -- Endoplasmic reticulum -- Golgi apparatus -- SOCE; Calcium -- Metabolism -- Periodicals; Vertebrates -- Physiology -- Periodicals; Calcium -- Physiological effect -- Periodicals; Cell physiology -- Periodicals; Calcium in the body -- Periodicals; 572.516
• DOI: 10.1016/j.ceca.2019.02.005
• Languages: English
• ISSNs: 0143-4160

Abstract

Graphical abstract: Highlights: FAD PS2, but not PS1, decrease the Ca 2+ content of the main intracellular stores. FAD PS2 mutants partially block SERCA activity. FAD PS1 and PS2 mutants reduce SOCE by decreasing the expression level of STIM1. Abstract: An imbalance in Ca 2+ homeostasis represents an early event in the pathogenesis of Alzheimer's disease (AD). Presenilin-1 and -2 (PS1 and PS2) mutations, the major cause of familial AD (FAD), have been extensively associated with alterations in different Ca 2+ signaling pathways, in particular those handled by storage compartments. However, FAD-PSs effect on organelles Ca 2+ content is still debated and the mechanism of action of mutant proteins is unclear. To fulfil the need of a direct investigation of intracellular stores Ca 2+ dynamics, we here present a detailed and quantitative single-cell analysis of FAD-PSs effects on organelle Ca 2+ handling using specifically targeted, FRET (Fluorescence/Förster Resonance Energy Transfer)-based Ca 2+ indicators. In SH-SY5Y human neuroblastoma cells and in patient-derived fibroblasts expressing different FAD-PSs mutations, we directly measured Ca 2+ concentration within the main intracellular Ca 2+ stores, e.g., Endoplasmic Reticulum (ER) and Golgi Apparatus (GA) medial- and trans-compartment. We unambiguously demonstrate that the expression of FAD-PS2 mutants, but not FAD-PS1, in either SH-SY5Y cells or FAD patient-derived fibroblasts, is able to alter Ca 2+ handling of ER and medial-GA, but not trans-GA, reducing, compared to control cells, the Ca 2+ content within these organelles by partially blocking SERCA (Sarco/Endoplasmic Reticulum Ca 2+ -ATPase) activity. Moreover, by using a cytosolic Ca 2+ probe, we show that the expression of both FAD-PS1 and -PS2 reduces the Ca 2+ influx activated by stores depletion (Store-Operated Ca 2+ Entry; SOCE), by decreasing the expression levels of one of the key molecules, STIM1 (STromal Interaction Molecule 1), controlling this pathway. Our data indicate that FAD-linked PSs mutants differentially modulate the Ca 2+ content of intracellular stores yet leading to a complex dysregulation of Ca 2+ homeostasis, which represents a common disease phenotype of AD.