Pathogenic mutant huntingtin (mHTT) infiltrates the adult Huntington’s disease (HD) brain and impairs fetal corticogenesis. However, most HD animal models rarely recapitulate neuroanatomical alterations in adult HD and developing brains. Thus, the human cortical organoid (hCO) is an alternative approach to decode mHTT pathogenesis precisely during human corticogenesis. Here, we replicated the altered corticogenesis in the HD fetal brain using HD patient-derived hCOs. Our HD-hCOs had pathological phenotypes, including deficient junctional complexes in the neural tubes, delayed postmitotic neuronal maturation, dysregulated fate specification of cortical neuron subtypes, and abnormalities in early HD subcortical projections during corticogenesis, revealing a causal link between impaired progenitor cells and chaotic cortical neuronal layering in the HD brain. We identified novel long, oriented, and enriched polyQ assemblies of HTTs that hold large flat Golgi stacks and scaffold clathrin+ vesicles in the neural tubes of hCOs. Flat Golgi stacks conjugated polyQ assemblies by ADP-ribosylation factor 1 (ARF1). Inhibiting ARF1 activation with Brefeldin A (BFA) disassociated polyQ assemblies from Golgi. PolyQ assembles with mHTT scaffolded fewer ARF1 and formed shorter polyQ assembles with fewer and shorter Golgi and clathrin vesicles in neural tubes of HD-hCOs compared with those in hCOs. Inhibiting the activation of ARF1 by BFA in healthy hCOs replicated impaired junctional complexes in the neural tubes. Together, endogenous polyQ assemblies with mHTT reduced the Golgi recruiting ARF1 in the neuroepithelium, impaired the Golgi structure and activities, and altered the corticogenesis in HD-hCO.

致病性突变亨廷顿蛋白 (mHTT) 会渗入成人亨廷顿病 (HD) 大脑并损害胎儿皮质生成。然而，大多数 HD 动物模型很少重现成人 HD 和发育中大脑的神经解剖学改变。因此，人类皮质类器官 (hCO) 是在人类皮质生成过程中精确解码 mHTT 发病机制的另一种方法。在这里，我们使用 HD 患者来源的 hCO 复制了 HD 胎儿大脑中改变的皮质生成。我们的 HD-hCO 具有病理表型，包括神经管中连接复合体的缺陷、有丝分裂后神经元成熟延迟、皮质神经元亚型的命运规范失调以及皮质发生过程中早期 HD 皮质下投射的异常，揭示了受损的祖细胞与混沌之间的因果关系HD 大脑中的皮质神经元分层。我们发现了新型长的、定向的、富集的 HTT 聚 Q 组装体，它们在 hCO 的神经管中容纳了大而平坦的高尔基体堆栈和支架网格蛋白+囊泡。扁平高尔基体通过 ADP-核糖基化因子 1 (ARF1) 堆叠缀合的 PolyQ 组件。使用布雷菲德菌素 A (BFA) 抑制 ARF1 激活，使高尔基体分离出 PolyQ 组件。与 hCO 中的神经管相比，HD-hCO 神经管中的 PolyQ 与 mHTT 组装的 ARF1 更少，并与更少且更短的高尔基体和网格蛋白囊泡形成更短的 PolyQ 组装。在健康的 hCO 中，BFA 抑制 ARF1 的激活会复制神经管中受损的连接复合物。总之，内源性 PolyQ 组装与 mHTT 减少了神经上皮中高尔基体募集 ARF1，损害了高尔基体结构和活性，并改变了 HD-hCO 中的皮质生成。