Project description:Genetic mutations on leucine-rich repeat kinase 2 (LRRK2) have been associated with an increased risk of Parkinson's disease. The Gly2019Ser (G2019S) mutation on LRRK2 gene is a relatively common cause of familial Parkinson's disease in Caucasian population. In this study, we generated H9 hESC harboring LRRK2 (G2019S) mutation by gene knockin. Wildtype and LRRK2 mutant hESC were differentiated into NSC using a chemically defined protocol. LRRK2 mutant NSC were treated with or without the LRRK2 kinase specific inhibitor (LRRK2-IN-1). Global gene expression analysis was performed to assess the overall similarity of gene expression profiles among three NSC groups (wildtype; LRRK2 mutant; LRRK2 mutant with inhibitor treatment).
Project description:Genetic mutations on leucine-rich repeat kinase 2 (LRRK2) have been associated with an increased risk of Parkinson's disease. The Gly2019Ser (G2019S) mutation on LRRK2 gene is a relatively common cause of familial Parkinson's disease in Caucasian population. In this study, we generated H9 hESC harboring LRRK2 (G2019S) mutation by gene knockin. Wildtype and LRRK2 mutant hESC were differentiated into NSC using a chemically defined protocol.
Project description:G2019S mutaion of LRRK2 is known to increase mRNA translation. We perform ribosome profiling to study defective translation using human dopamine neuron models. Patient-derived human dopamine neurons with G2019S LRRK2 mutation were generated and used. Also a mutation-corrected isogenic pair line was used.
Project description:LRRK2 is commonly mutated in Parkinson’s disease and has cell type-specific mechanisms of activation and function. In macrophages, LRRK2 is associated with lysosomes and is activated following lysosomal damage. However, the functional outcomes of clinically relevant pathogenic mutations in macrophages are unknown. Here, using primary mouse and patient-derived iPSC-derived macrophage (iPSDM) models of LRRK2-G2019S, we defined the substrates of LRRK2 after lysosomal damage. Using phosphoproteomics we found that LRRK2-G2019S and wild-type macrophages showed similar levels of Rab GTPases phosphorylation after lysosomal damage. However, the levels of pRab12 increased whereas the levels of pRab35 decreased in LRRK2-G2019S macrophages. Functionally, LRRK2-G2019S macrophages showed a deficit in lysosomal membrane repair that resulted in more cell death and increased apoptosis. Importantly, we recapitulated this phenotype in iPSDM from patients carrying the G2019S mutation, but not in isogenic control iPSDM. Altogether, we define here the signaling downstream of G2019S in macrophages and identify susceptibility to cell death after lysosomal damage as an important phenotype of this mutation.
Project description:Recent advances in generating 3 dimensional (3D) organoid systems from stem cells offer new possibilities for disease modeling. In this study, we generate isogenic 3D midbrain organoids with or without a Parkinson’s disease-associated LRRK2 G2019S mutation. LRRK2-G2019S midbrain organoids derived from LRRK2 targeted human iPSCs in vitro have LRRK2-associated sporadic Parkinson's disease phenotypes. Midbrain-like 3D organoids expressing LRRK2-G2019S showed dynamic changes in globle gene expression.
Project description:In this study, we generated wildtype H9 hESC derived cardiomyocytes (CM) and neural stem cells (NSC) by in vitro differentiation. Global gene expression profiles were compared among undifferentiated H9 hESC and the derived CM and NSC. Comparison of global gene expression profiles of undifferentiated H9 hESC and the derived CM and NSC populations.
Project description: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.
Project description:In this study, we generated wildtype H9 hESC derived cardiomyocytes (CM) and neural stem cells (NSC) by in vitro differentiation. Global gene expression profiles were compared among undifferentiated H9 hESC and the derived CM and NSC.
Project description:Under metabolic stress, the LRRK2-G2019S mutation accelerates astrocytic senescence by physically sequestering DDB1. This aberrant interaction impedes the CUL4–DDB1-mediated proteasomal degradation of p21, leading to massive p21 accumulation, an exacerbated senescence-associated secretory phenotype (SASP), and subsequent neurodegeneration. Crucially, non-invasive LED-PBM dismantles this pathogenic axis by selectively disrupting the LRRK2–DDB1 interaction, thereby restoring p21 clearance and uncoupling metabolic dysfunction from neuronal injury. Transcriptomic profiling via microarray was employed to unbiasedly interrogate global gene network alterations driven by the interaction between metabolic stress and the LRRK2-G2019S mutation
Project description:Genetic mutations on leucine-rich repeat kinase 2 (LRRK2) have been associated with an increased risk of Parkinson's disease. The Gly2019Ser (G2019S) mutation on LRRK2 gene is a relatively common cause of familial Parkinson's disease in Caucasian population. In this study, we generated human induced pluripotent stem cell (iPSC) lines from LRRK2 (G2019S) bearing patient fibroblasts by cell reprogramming. We performed global gene expression profiling of LRRK2 (G2019S) heterozygous and homozygous patient iPSC lines, and the corresponding fibroblast lines they originated from. An age-matched wildtype human fibroblast line and H1 human embryonic stem cell (ESC) line were used as controls. Microarray gene expression profiling was done to: (1) Compare global gene expression differences between wildtype fibroblasts and fibroblasts from patients bearing homozygous and heterozygous LRRK2 (G2019S) mutation; (2) Compare global gene expression differences between wildtype iPSC and iPSC generated from LRRK2 (G2019S) homozygous and heterozygous patients; (3) Check that all iPSC generated from wildtype and patients fibroblasts are in fact similar to human pluripotent ESC.