Department of Biomedical Science, College of Medicine, Seoul National University, Seoul, Korea.
Dementia Research Center, Seoul National University College of Medicine, Seoul, Korea.
Exp Mol Med. 2022 Sep;54(9):1461-1471. doi: 10.1038/s12276-022-00841-w. Epub 2022 Sep 2.
Mitochondria in neural progenitors play a crucial role in adult hippocampal neurogenesis by being involved in fate decisions for differentiation. However, the molecular mechanisms by which mitochondria are related to the genetic regulation of neuronal differentiation in neural progenitors are poorly understood. Here, we show that mitochondrial dysfunction induced by amyloid-beta (Aβ) in neural progenitors inhibits neuronal differentiation but has no effect on the neural progenitor stage. In line with the phenotypes shown in Alzheimer's disease (AD) model mice, Aβ-induced mitochondrial damage in neural progenitors results in deficits in adult hippocampal neurogenesis and cognitive function. Based on hippocampal proteome changes after mitochondrial damage in neural progenitors identified through proteomic analysis, we found that lysine demethylase 5A (KDM5A) in neural progenitors epigenetically suppresses differentiation in response to mitochondrial damage. Mitochondrial damage characteristically causes KDM5A degradation in neural progenitors. Since KDM5A also binds to and activates neuronal genes involved in the early stage of differentiation, functional inhibition of KDM5A consequently inhibits adult hippocampal neurogenesis. We suggest that mitochondria in neural progenitors serve as the checkpoint for neuronal differentiation via KDM5A. Our findings not only reveal a cell-type-specific role of mitochondria but also suggest a new role of KDM5A in neural progenitors as a mediator of retrograde signaling from mitochondria to the nucleus, reflecting the mitochondrial status.
神经祖细胞中的线粒体通过参与分化命运决定,在成年海马神经发生中发挥着关键作用。然而,线粒体与神经祖细胞中神经元分化的遗传调控相关的分子机制还知之甚少。在这里,我们表明,神经祖细胞中的β淀粉样蛋白(Aβ)诱导的线粒体功能障碍抑制神经元分化,但对神经祖细胞阶段没有影响。与阿尔茨海默病(AD)模型小鼠中显示的表型一致,Aβ诱导的神经祖细胞中线粒体损伤导致成年海马神经发生和认知功能缺陷。基于通过蛋白质组学分析鉴定的神经祖细胞中线粒体损伤后的海马蛋白质组变化,我们发现神经祖细胞中的赖氨酸去甲基酶 5A(KDM5A)通过表观遗传抑制分化来响应线粒体损伤。线粒体损伤特征性地导致神经祖细胞中的 KDM5A 降解。由于 KDM5A 还结合并激活涉及分化早期的神经元基因,因此 KDM5A 的功能抑制会导致成年海马神经发生。我们认为,神经祖细胞中的线粒体通过 KDM5A 作为神经元分化的检查点。我们的发现不仅揭示了线粒体在特定细胞类型中的作用,还表明 KDM5A 在神经祖细胞中作为线粒体到核的逆行信号的中介具有新作用,反映了线粒体的状态。