Selvaraj Bhuvaneish T, Livesey Matthew R, Zhao Chen, Gregory Jenna M, James Owain T, Cleary Elaine M, Chouhan Amit K, Gane Angus B, Perkins Emma M, Dando Owen, Lillico Simon G, Lee Youn-Bok, Nishimura Agnes L, Poreci Urjana, Thankamony Sai, Pray Meryll, Vasistha Navneet A, Magnani Dario, Borooah Shyamanga, Burr Karen, Story David, McCampbell Alexander, Shaw Christopher E, Kind Peter C, Aitman Timothy J, Whitelaw C Bruce A, Wilmut Ian, Smith Colin, Miles Gareth B, Hardingham Giles E, Wyllie David J A, Chandran Siddharthan
MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, EH16 4UU, UK.
Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB, UK.
Nat Commun. 2018 Jan 24;9(1):347. doi: 10.1038/s41467-017-02729-0.
Mutations in C9ORF72 are the most common cause of familial amyotrophic lateral sclerosis (ALS). Here, through a combination of RNA-Seq and electrophysiological studies on induced pluripotent stem cell (iPSC)-derived motor neurons (MNs), we show that increased expression of GluA1 AMPA receptor (AMPAR) subunit occurs in MNs with C9ORF72 mutations that leads to increased Ca-permeable AMPAR expression and results in enhanced selective MN vulnerability to excitotoxicity. These deficits are not found in iPSC-derived cortical neurons and are abolished by CRISPR/Cas9-mediated correction of the C9ORF72 repeat expansion in MNs. We also demonstrate that MN-specific dysregulation of AMPAR expression is also present in C9ORF72 patient post-mortem material. We therefore present multiple lines of evidence for the specific upregulation of GluA1 subunits in human mutant C9ORF72 MNs that could lead to a potential pathogenic excitotoxic mechanism in ALS.
C9ORF72基因的突变是家族性肌萎缩侧索硬化症（ALS）最常见的病因。在此，通过对诱导多能干细胞（iPSC）衍生的运动神经元（MNs）进行RNA测序和电生理研究相结合，我们发现，在携带C9ORF72突变的运动神经元中，谷氨酸A1型离子型谷氨酸受体（AMPAR）亚基的表达增加，这导致钙通透性AMPAR表达增加，并导致运动神经元对兴奋性毒性的选择性易损性增强。这些缺陷在iPSC衍生的皮质神经元中未发现，并且通过CRISPR/Cas9介导的运动神经元中C9ORF72重复扩增的校正而消除。我们还证明，在C9ORF72患者的尸检材料中也存在运动神经元特异性的AMPAR表达失调。因此，我们提供了多条证据，证明人类突变C9ORF72运动神经元中谷氨酸A1亚基的特异性上调，这可能导致ALS中潜在的致病性兴奋性毒性机制。
