(a) Phenotypic screening for small molecules that enhance the survival of C9-ALS iMNs. (b) Chemical structure of the PIKFYVE inhibitors YM201636 and Apilimod, and a reduced-activity analog of Apilimod. (c) Live cell images of iMNs at day 7 of treatment with DMSO or YM201636 (scale bar: 1 mm). This experiment was performed 3 times with similar results. (d) Survival effect of scrambled or PIFKVYE ASOs on C9-ALS iMNs in excess glutamate. n=50 iMNs per condition, iMNs quantified from 3 biologically independent iMN conversions per condition. (e) Survival effect of Apilimod and the reduced-activity analog on C9-ALS patient iMNs with neurotrophic factor withdrawal. n=50 iMNs per condition, iMNs quantified from 3 biologically independent iMN conversions per condition. All iMN survival experiments in (d, e) were analyzed by two-sided log-rank test, and statistical significance was calculated using the entire survival time course. (f) Activities of therapeutic targets in C9ORF72 ALS. (g, h) The effect of 3 μM Apilimod on NMDA-induced hippocampal injury in control, C9orf72+/−, or C9orf72−/− mice. (Mean +/− s.e.m. of n=3 mice per condition, one-way ANOVA with Tukey correction across all comparisons, F-value (DFn, DFd): (3, 8)=43.55, AP = Apilimod, red dashed lines outline the injury sites). (i, j) The effect of 3 μM Apilimod on the level of GR+ puncta in the dentate gyrus of control or C9-BAC mice. Mean +/− s.d. of the number of GR+ puncta per cell, each data point represents a single cell. n=20 (wild-type + DMSO), 20 (wild-type + Apilimod), 87 (C9-BAC + DMSO), and 87 (C9-BAC + Apilimod) cells quantified from 3 mice per condition, one-way ANOVA with Tukey correction for all comparisons, F-value (DFn, DFd): (3, 180) = 16.29. Scale bars = 2 μm, dotted lines outline nuclei, and white arrows denote GR+ punctae (i). (k) Model for the mechanisms that cooperate to cause neurodegeneration in C9ORF72 ALS/FTD. Proteins in red are known to be mutated in ALS or FTD. iMN survival experiments in (d, e) were performed in a Molecular Devices ImageExpress.
Although studies in mice have indicated that C9orf72 activity is important for myeloid cell function 14,18, a report in mouse neurons and zebrafish suggests that C9orf72 isoform A may modulate poly-Q Ataxin-2 toxicity 20, and studies have implicated C9ORF72 in regulating autophagy 20,31,32,38, our study provides the first direct evidence showing that gain- and loss-of-function C9ORF72 mechanisms cooperate to cause the degeneration of human motor neurons. Recent studies have shown that C9ORF72 isoform A, but not isoform B, can form a functional complex with SMCR8 and WDR41 20. However, since both C9ORF72 isoforms rescue C9-ALS iMN degeneration in our assay, other mechanisms or protein interactions may underlie the rescue of patient iMNs.
The fabrication of composite cathode with boroxine ring for all-solid-polymer lithium cell was described. Composite polymer electrolyte (CPE) was applied between the lithium metal anode and the composite cathode in a coin-shaped cell in order to prepare the solid-polymer electrolyte cell. The CPE films were cast on a flat polytetrafluoroethylene vessel from an acetonitrile slurry containing BaTiO ... [Show full abstract]Read more

To examine C9ORF72 function, we determined its localization in iMNs. We first used an HA-tagged C9ORF72 construct to verify that the C9ORF72 antibody specifically recognizes C9ORF72 in cells (Supplementary Fig. 7a). In iMNs, C9ORF72 co-localized to cytoplasmic puncta and ASO-mediated knockdown of C9ORF72 expression reduced the number of antibody-detected cytoplasmic puncta in iMNs, indicating that the antibody specifically recognizes C9ORF72 in these puncta (Supplementary Fig. 7b, c). Super-resolution microscopy and z-stack imaging showed that about 80% of the C9ORF72+ vesicles also expressed the early endosomal proteins RAB5 and EEA1 (Fig. 3a and Supplementary 7d-h). Only rarely did C9ORF72 co-localize with the lysosomal marker LAMP1 (20%)(Supplementary Fig. 7e), and control and patient iMNs showed similar C9ORF72 localization (Supplementary Fig. 7h). We performed density gradient centrifugation on lysates from iPSC-derived motor neurons to separate light (endosomal) and heavy (lysosomal) membrane fractions. C9ORF72 co-segregated with EEA1 and not LAMP1, supporting the notion that C9ORF72 localizes predominantly in early endosomes (Fig. 3b, Supplementary Fig. 5d). In addition, we found that C9ORF72 isoform B bound strongly to an immobilized N-terminal fragment of EEA1 (Supplementary Fig. 7i). C9ORF72 isoform A did not interact as strongly with EEA1 (Supplementary Fig. 7i). The fact that not all EEA1+ vesicles contained high levels of C9ORF72 is consistent with this hypothesis and suggests that C9ORF72 may not localize to all types of EEA1+ vesicles (Fig. 3a).
Reprogramming was performed in 96-well plates (8 × 103 cells/well) or 13mm plastic coverslips (3.2 × 104 cells/coverslip) that were sequentially coated with gelatin (0.1%, 1 hour) and laminin (2–4 hours) at room temperature. To enable efficient expression of the transgenic reprogramming factors, iPSCs were cultured in fibroblast medium (DMEM + 10% FBS) for at least 48 hours and either used directly for retroviral transduction or passaged before transduction for each experiment. 7 iMN factors or 5 iDA factors were added in 100–200 µl fibroblast medium per 96-well well with 5 μg/ml polybrene. For iMNs, cultures were transduced with lentivirus encoding the Hb9::RFP reporter 48 hours after transduction with transcription factor-encoding retroviruses. On day 5, primary mouse cortical glial cells from P1 ICR pups (male and female) were added to the transduced cultures in glia medium containing MEM (Life Technologies), 10% donor equine serum (HyClone), 20% glucose (Sigma-Aldrich), and 1% penicillin/streptomycin. On day 6, cultures were switched to N3 medium containing DMEM/F12 (Life Technologies), 2% FBS, 1% penicillin/streptomycin, N2 and B27 supplements (Life Technologies), 7.5 µM RepSox (Selleck), and 10 ng/ml each of GDNF, BDNF, and CNTF (R&D). The iMN and iDA neuron cultures were maintained in N3 medium, changed every other day, unless otherwise noted.

Immunostaining revealed that C9ORF72+/− and C9ORF72−/− iMNs contained elevated levels of NMDA (NR1) and AMPA (GLUR1) receptors on neurites and dendritic spines compared to control iMNs under basal conditions (Fig. 4a, c, d and Supplementary Fig. 5b and 10a, c-e, g, h, j, k). In addition, control iMNs treated with C9ORF72-specific ASOs displayed increased numbers of NMDA and AMPA receptors in their neurites (Supplementary Fig. 10l, m). C9ORF72 patient iMNs (n=3 patients) also showed elevated NR1 and GLUR1 levels compared to controls (n=3 controls), and forced expression of C9ORF72 isoform B reduced glutamate receptor levels in patient iMNs (n=3 patients) to that of controls (n=3 controls) (Fig. 4a-c and Supplementary Fig. 10a-h). mRNA levels of NR1 (GRIN1) and GLUR1 (GRIA1) were not elevated in flow-purified C9ORF72+/− iMNs, indicating that increased transcription could not explain the increased glutamate receptor levels (Supplementary Fig. 10n).
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