Heman-Ackah Sabrina M, Manzano Raquel, Hoozemans Jeroen J M, Scheper Wiep, Flynn Rowan, Haerty Wilfried, Cowley Sally A, Bassett Andrew R, Wood Matthew J A
Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK.
NIH Oxford-Cambridge Scholars Program, National Institutes of Health, Bethesda, MD 20892, USA.
Hum Mol Genet. 2017 Nov 15;26(22):4441-4450. doi: 10.1093/hmg/ddx331.
The recent generation of induced pluripotent stem cells (iPSCs) from a patient with Parkinson's disease (PD) resulting from triplication of the α-synuclein (SNCA) gene locus allows unprecedented opportunities to explore its contribution to the molecular pathogenesis of PD. We used the double-nicking CRISPR/Cas9 system to conduct site-specific mutagenesis of SNCA in these cells, generating an isogenic iPSC line with normalized SNCA gene dosage. Comparative gene expression analysis of neuronal derivatives from these iPSCs revealed an ER stress phenotype, marked by induction of the IRE1α/XBP1 axis of the unfolded protein response (UPR) and culminating in terminal UPR activation. Neuropathological analysis of post-mortem brain tissue demonstrated that pIRE1α is expressed in PD brains within neurons containing elevated levels of α-synuclein or Lewy bodies. Having used this pair of isogenic iPSCs to define this phenotype, these cells can be further applied in UPR-targeted drug discovery towards the development of disease-modifying therapeutics.
近期，从一名因α-突触核蛋白（SNCA）基因座三倍体导致的帕金森病（PD）患者中产生的诱导多能干细胞（iPSC），为探索其在PD分子发病机制中的作用提供了前所未有的机会。我们使用双切口CRISPR/Cas9系统对这些细胞中的SNCA进行位点特异性诱变，生成了一个SNCA基因剂量正常化的同基因iPSC系。对这些iPSC的神经元衍生物进行的比较基因表达分析揭示了一种内质网应激表型，其特征是未折叠蛋白反应（UPR）的IRE1α/XBP1轴被诱导，并最终导致UPR的终末激活。对死后脑组织的神经病理学分析表明，磷酸化IRE1α在含有高水平α-突触核蛋白或路易小体的神经元内的PD脑中表达。利用这对同基因iPSC定义了这种表型后，这些细胞可进一步应用于针对UPR的药物发现，以开发疾病修饰疗法。
