Synergistic Interaction of FTD Genes in Neuroinflammation and Neurodegeneration

FTD 基因在神经炎症和神经变性中的协同相互作用

基本信息

批准号：
10551203
负责人：
Naznin Jahan
金额：
$ 4.52万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-12 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10551203
关键词：
3-Dimensional Affect Aging Autophagocytosis Biochemistry Biological Models Brain Brain Pathology Brain region C9ORF72 CRISPR/Cas technology Cell Nucleus Cells Cellular biology Central Nervous System Clinical Research Coculture Techniques Cytoplasm Data Data Set Dementia Disease Disease Progression Exhibits Fellowship Foundations Frontotemporal Dementia Future GRN gene Genes Genetic Gliosis Goals Homeostasis Human Immune Immune system Immunohistochemistry In Situ Hybridization In Vitro Knockout Mice Limbic System Longevity Lysosomes Mediating Microglia Modeling Mus Mutation Nerve Degeneration Neurodegenerative Disorders Neuroglia Neurons Organoids PGRN gene Pathogenesis Pathway interactions Patients Phase Phenotype Postdoctoral Fellow Proteins RNA-Binding Proteins Reporting Research Scientist Signal Pathway TDP-43 aggregation Testing Thalamic structure Therapeutic Toxic effect Training Ubiquitin Western Blotting Wild Type Mouse Work age related aging brain astrogliosis career cerebral atrophy chromosome 9 loss cohort dominant genetic mutation early onset induced pluripotent stem cell insight loss of function mouse model neuroinflammation neuron loss neuropathology neurotoxicity null mutation protein TDP-43 protein aggregation therapeutic target transcriptome sequencing transcriptomics

项目摘要

Project Summary Frontotemporal dementia (FTD) is an early onset neurodegenerative disease, and the second most common cause of dementia in patients 60 years or younger. The majority of familial FTD are caused by intronic hexanucleotide (CCCCGG) repeat expansion in chromosome 9 open reading frame 72 (C9orf72) gene and by dominant mutations in the Progranulin (GRN) gene, causing haploinsufficiency in both genes, abnormal protein aggregate formation in neurons. Several functional and transcriptomic studies have shown that mice with null mutation in C9orf72 or Grn show abnormal microglia (resident CNS immune cells) activation mediated pathogenesis of neurodegeneration in FTD. While the exact functions for C9orf72 and Progranulin (PGRN [protein]) are still unclear, several studies have implicated both in autophagy and endolysosomal pathways in neurons and microglia, and concurrent mutations resulting in increased brain atrophy in patients. These results suggest a possible interaction between C9orf72 and PGRN in neurodegeneration during brain aging The goal of my project is to investigate the synergistic interaction of C9orf72 and Grn genes in glial homeostasis and neuronal degeneration using mouse models. In support of this, my preliminary data showed that C9orf72-/- ;Grn-/- DKO mice have significantly shortened lifespan, much shorter than C9orf72-/- mice, Grn-/- mice and control mice. Brain pathology examination in C9orf72-/-;Grn-/- DKO mice showed age-dependent gliosis as well as neuronal TDP-43 aggregates that are more pronounced and wide-spread than those in C9orf72-/- or Grn-/- mice. These results support my hypothesis and further indicate that loss of C9orf72 and Grn synergistically disrupt glia-neuron homeostasis and lead to more pronounced neurodegeneration phenotype. For the F00 phase, I propose to uncover the mechanism of C9 and PGRN in neurodegeneration in the aging brain via single-cell and bulk RNA-sequencing in 7 and 12 months old control, C9orf72-/-, Grn-/- and C9orf72-/-;Grn-/- DKO brain to determine how loss of these two FTD genes disrupts the homeostasis in glia-neuron interaction (Aim 2a). These transcriptomic data will be validated using in situ hybridization, immunohistochemistry and western blots (Aim 2b). Finally, I propose to develop in vitro cultures, including neuron-only cultures and glia-neuron co-cultures, which will provide more insights into the synergistic interaction between C9orf72 and PGRN in the autophagy- lysosome pathways and in glia-mediated toxicity to neurons (Aim 2c). For the K00 phase of this fellowship, I plan to develop induced pluripotent stem cells (IPSC)-derived 3D brain organoids as model systems to investigate disease mechanism and identify therapeutics for neurodegeneration. To identify signaling pathways that could be affected by diseases, I plan on using single-cell transcriptomics on patient IPSC derived glia-neuron organoids, followed by CRISPR/Cas9-based manipulation strategies on the signaling pathways dysregulated in these brain organoids to elucidate the diseases progression mechanisms.

项目摘要额颞痴呆（FTD）是一种早期发作神经退行性疾病，是第二常见的 60岁以下的患者痴呆症原因。大多数家族FTD是由内含子引起的六核苷酸（CCCCGG）在9号染色体上的重复扩展72（C9orf72）基因和通过前植物（GRN）基因中的主要突变，导致两个基因的单倍症，异常蛋白神经元中的骨料形成。一些功能和转录组研究表明，无效的小鼠 C9ORF72或GRN中的突变表现出异常的小胶质细胞（常驻CNS免疫细胞）激活介导 FTD中神经退行性的发病机理。而C9ORF72和PROGRANULIN的确切功能（PGRN [蛋白质]）尚不清楚，几项研究都与自噬和内溶性途径有关神经元和小胶质细胞以及并发突变导致患者脑萎缩增加。这些结果建议在大脑衰老过程中C9ORF72和PGRN之间可能存在相互作用我项目的目的是研究胶质稳态中C9orf72和GRN基因的协同相互作用和使用小鼠模型的神经元变性。为此，我的初步数据表明C9orf72 - / - ; GRN - / - DKO小鼠的寿命明显缩短，比C9orf72 - / - 小鼠短得多，GRN - / - 小鼠和对照老鼠。 C9ORF72 - / - ; GRN-/ - DKO小鼠的脑病理检查表现出年龄依赖性神经胶质和与c9orf72 - / - 或grn-/ - 小鼠相比，神经元TDP-43聚集体更为明显，更广泛。这些结果支持我的假设，并进一步表明C9orf72和GRN的丧失协同破坏神经胶质神经元稳态，导致更明显的神经变性表型。对于F00阶段，我建议通过单细胞在衰老脑中神经变性中发现C9和PGRN的机制在7和12个月大的对照中进行批量RNA - c9orf72 - / - ，grn - / - 和c9orf72 - / - ; grn - / - dko大脑到确定这两个FTD基因的丧失如何破坏神经胶质神经元相互作用的稳态（AIM 2A）。这些转录组数据将使用原位杂交，免疫组织化学和蛋白质印迹验证（AIM 2b）。最后，我建议开发体外培养物，包括仅神经元的培养物和神经胶质神经元共培养，这将为自噬中的C9orf72和PGRN之间的协同相互作用提供更多的见解。溶酶体途径和胶质介导的对神经元的毒性（AIM 2C）。对于此研究金的K00阶段，我计划开发诱导的多能干细胞（IPSC）衍生的3D脑器官作为模型系统研究疾病机制并鉴定神经退行性的治疗剂。要识别可能受疾病影响的信号通路，我计划在上使用单细胞转录组学患者IPSC衍生的神经胶质神经元器官，然后是基于CRIS/CAS9的操纵策略信号通路在这些脑器官中失调，以阐明疾病的进展机制。