Ludtmann Marthe H R, Arber Charles, Bartolome Fernando, de Vicente Macarena, Preza Elisavet, Carro Eva, Houlden Henry, Gandhi Sonia, Wray Selina, Abramov Andrey Y
From the Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3BG, United Kingdom.
the Neurodegenerative Disorders Group, Research Institute Hospital 12 de Octubre (i+12), Madrid 28041, Spain.
J Biol Chem. 2017 May 26;292(21):8907-8917. doi: 10.1074/jbc.M116.762898. Epub 2017 Mar 30.
Mutations in the gene encoding valosin-containing protein (VCP) lead to multisystem proteinopathies including frontotemporal dementia. We have previously shown that patient-derived mutant fibroblasts exhibit lower mitochondrial membrane potential, uncoupled respiration, and reduced ATP levels. This study addresses the underlying basis for mitochondrial uncoupling using knockdown neuroblastoma cell lines, induced pluripotent stem cells (iPSCs), and iPSC-derived cortical neurons from patients with pathogenic mutations in Using fluorescent live cell imaging and respiration analysis we demonstrate a mutation/knockdown-induced dysregulation in the adenine nucleotide translocase, which results in a slower rate of ADP or ATP translocation across the mitochondrial membranes. This deregulation can explain the mitochondrial uncoupling and lower ATP levels in VCP mutation-bearing neurons via reduced ADP availability for ATP synthesis. This study provides evidence for a role of adenine nucleotide translocase in the mechanism underlying altered mitochondrial function in VCP-related degeneration, and this new insight may inform efforts to better understand and manage neurodegenerative disease and other proteinopathies.
编码含缬酪肽蛋白(VCP)的基因突变会导致包括额颞叶痴呆在内的多系统蛋白病。我们之前已经表明,源自患者的突变成纤维细胞表现出线粒体膜电位降低、呼吸解偶联以及ATP水平降低。本研究利用敲低神经母细胞瘤细胞系、诱导多能干细胞(iPSC)以及来自携带致病突变患者的iPSC衍生的皮质神经元,探讨了线粒体解偶联的潜在机制。通过荧光活细胞成像和呼吸分析,我们证明了腺嘌呤核苷酸转位酶的突变/敲低诱导的失调,这导致ADP或ATP跨线粒体膜的转运速率减慢。这种失调可以通过降低ATP合成可用的ADP来解释携带VCP突变的神经元中的线粒体解偶联和较低的ATP水平。本研究为腺嘌呤核苷酸转位酶在VCP相关变性中线粒体功能改变的潜在机制中的作用提供了证据,这一新见解可能有助于更好地理解和管理神经退行性疾病及其他蛋白病。