Department of Physiology, University of California Los Angeles, Los Angeles, CA 90095-1751, USA.
Department of Biological Chemistry, University of California Los Angeles, Los Angeles, CA 90095-1751, USA.
Cell Rep. 2023 Jan 31;42(1):111953. doi: 10.1016/j.celrep.2022.111953. Epub 2023 Jan 7.
Huntington's disease (HD) is caused by expanded CAG repeats in the huntingtin gene (HTT) resulting in expression of mutant HTT proteins (mHTT) with extended polyglutamine tracts, including in striatal neurons and astrocytes. It is unknown whether pathophysiology in vivo can be attenuated by lowering mHTT in either cell type throughout the brain, and the relative contributions of neurons and astrocytes to HD remain undefined. We use zinc finger protein (ZFP) transcriptional repressors to cell-selectively lower mHTT in vivo. Astrocytes display loss of essential functions such as cholesterol metabolism that are partly driven by greater neuronal dysfunctions, which encompass neuromodulation, synaptic, and intracellular signaling pathways. Using transcriptomics, proteomics, electrophysiology, and behavior, we dissect neuronal and astrocytic contributions to HD pathophysiology. Remarkably, brain-wide delivery of neuronal ZFPs results in strong mHTT lowering, rescue of HD-associated behavioral and molecular phenotypes, and significant extension of lifespan, findings that support translational development.
亨廷顿病（HD）是由亨廷顿基因（HTT）中的 CAG 重复扩展引起的，导致突变 HTT 蛋白（mHTT）的表达，其具有延伸的多聚谷氨酰胺片段，包括纹状体神经元和星形胶质细胞。目前尚不清楚通过降低整个大脑中这两种细胞类型中的 mHTT 是否可以减轻体内的病理生理学，神经元和星形胶质细胞对 HD 的相对贡献仍未确定。我们使用锌指蛋白（ZFP）转录抑制剂在体内选择性地降低 mHTT。星形胶质细胞表现出丧失胆固醇代谢等必需功能，这些功能部分是由更大的神经元功能障碍驱动的，其中包括神经调节、突触和细胞内信号通路。通过转录组学、蛋白质组学、电生理学和行为学，我们剖析了神经元和星形胶质细胞对 HD 病理生理学的贡献。值得注意的是，脑内广泛递送神经元 ZFPs 可显著降低 mHTT，挽救与 HD 相关的行为和分子表型，并显著延长寿命，这些发现支持了转化发展。
