Genome-wide expression profiling of the LRRK2-G2019S mutation in hNES cells

Parkinson’s disease (PD) has a neuro-developmental component with multiple genetic predispositions. The most prevalent mutation, LRRK2-G2019S is linked to familial and sporadic PD. Based on the multiple origins of PD and the incomplete penetrance of LRRK2-G2019S, we hypothesize that modifiers in the patient genetic background act as susceptibility factors for developing PD. To assess the developmental component of LRRK2-G2019S pathogenesis, we used 19 human iPSC-derived neuroepithelial stem cell lines (NESCs). Isogenic controls distinguish between LRRK2-G2019S dependent and independent cellular phenotypes. LRRK2-G2019S patient and healthy mutagenized lines showed altered NESC self-renewal. Within patients, phenotypes were only partly LRRK2-G2019S dependent, suggesting Parkinson’s disease (PD) has a neuro-developmental component with multiple genetic predispositions. The most prevalent mutation, LRRK2-G2019S is linked to familial and sporadic PD. Based on the multiple origins of PD and the incomplete penetrance of LRRK2-G2019S, we hypothesize that modifiers in the patient genetic background act as susceptibility factors for developing PD. To assess the developmental component of LRRK2-G2019S pathogenesis, we used 19 human iPSC-derived neuroepithelial stem cell lines (NESCs). Isogenic controls distinguish between LRRK2-G2019S dependent and independent cellular phenotypes. LRRK2-G2019S patient and healthy mutagenized lines showed altered NESC self-renewal. Within patients, phenotypes were only partly LRRK2-G2019S dependent, suggesting a significant contribution of the genetic background. We identified Serine racemase (SRR) as a novel patient-specific, developmental, genetic modifier contributing to the abberant phenotypes. Its enzymatic product, D-Serine, rescued altered NESC renewal. Susceptibility factors in the genetic background, such as SRR, could be new targets for early PD diagnosis and treatment. 51 samples analyzed, 4 outliers excluded based on QC, 17 coditions, 3 biological replicates, 6 LRRK2G2019S patients, 6 healthy indiviuals, 3 gene corrected lines, 2 inserted mutated lines

帕金森病（Parkinson’s disease, PD）存在伴随多种遗传易感倾向的神经发育致病组分。其中最常见的突变LRRK2-G2019S与家族性和散发性帕金森病均存在关联。鉴于帕金森病存在多种致病起源，且LRRK2-G2019S具有不完全外显率，我们提出假说：患者遗传背景中的遗传修饰因子可作为帕金森病发病的易感因素。为评估LRRK2-G2019S致病机制中的神经发育组分，我们使用了19株人诱导多能干细胞（induced pluripotent stem cell, iPSC）诱导产生的神经上皮干细胞系（neuroepithelial stem cell lines, NESCs）。同基因对照可用于区分LRRK2-G2019S依赖与非依赖的细胞表型。LRRK2-G2019S患者来源细胞系与健康对照诱变细胞系均表现出神经上皮干细胞自我更新能力异常。在患者群体中，表型仅部分依赖LRRK2-G2019S，提示遗传背景对疾病进程存在显著贡献。我们鉴定出丝氨酸消旋酶（Serine racemase, SRR）作为一种新型患者特异性、发育相关的遗传修饰因子，参与异常细胞表型的发生。其酶促产物D-丝氨酸可挽救神经上皮干细胞自我更新的异常表现。遗传背景中的易感因子（如SRR）或可成为帕金森病早期诊断与治疗的新型靶点。本研究共分析51份样本，经质量控制（quality control, QC）剔除4份异常样本，涵盖17种实验条件，设置3次生物学重复；其中包含6株LRRK2-G2019S患者来源细胞系、6株健康个体来源细胞系、3株基因校正细胞系以及2株插入突变细胞系。