A reduction in Drp1-mediated fission compromises mitochondrial health in autosomal recessive spastic ataxia of Charlevoix Saguenay.
A reduction in Drp1-mediated fission compromises mitochondrial health in autosomal recessive spastic ataxia of Charlevoix Saguenay.
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DOI：
10.1093/hmg/ddw173
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发表时间：
2016-08-01
影响因子：
3.5
通讯作者：
Chapple JP
中科院分区：
文献类型：
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作者：
Bradshaw TY;Romano LE;Duncan EJ;Nethisinghe S;Abeti R;Michael GJ;Giunti P;Vermeer S;Chapple JP
Charlevoix Saguenay的常染色体隐性遗传性痉挛性共济失调（ARSACS）是由sacsin功能丧失引起的，sacsin是一种正常线粒体网络组织所需的模块蛋白。为了进一步了解sacsin缺失的细胞后果，我们在sacsin敲低细胞和ARSACS患者成纤维细胞中进行了微阵列分析。这确定了氧化磷酸化和氧化应激基因的转录水平改变。线粒体基因网络中的这些变化通过定量逆转录PCR进行验证。然后通过细胞外通量分析比较线粒体生物能量学来证明氧化磷酸化的功能障碍。此外，用细胞特异性荧光探针MitoSox染色表明，在sacsin水平降低的情况下，患者细胞中的超氧化物水平增加。维持线粒体健康的关键是线粒体分裂，其促进线粒体组分的动态交换并分离线粒体网络的受损部分以通过线粒体自噬进行选择性消除。分裂依赖于动力蛋白相关蛋白1（Drp1），它被招募到预期的分裂位点，在那里它介导分裂。在sacsin敲低细胞和ARSACS成纤维细胞中，我们观察到线粒体相关Drp1病灶的发生率降低。这种表型即使在药物治疗诱导裂变时也持续存在。线粒体相关的Drp1病灶在sacsin敲除细胞和ARSACS成纤维细胞中也较小。这些数据表明了一个ARSACS模型，其中具有降低的sacsin水平的神经元在其在线粒体膜上招募或保留Drp1的能力方面受到损害，导致线粒体健康下降，可能是通过受损的线粒体质量控制。
The neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix Saguenay (ARSACS) is caused by loss of function of sacsin, a modular protein that is required for normal mitochondrial network organization. To further understand cellular consequences of loss of sacsin, we performed microarray analyses in sacsin knockdown cells and ARSACS patient fibroblasts. This identified altered transcript levels for oxidative phosphorylation and oxidative stress genes. These changes in mitochondrial gene networks were validated by quantitative reverse transcription PCR. Functional impairment of oxidative phosphorylation was then demonstrated by comparison of mitochondria bioenergetics through extracellular flux analyses. Moreover, staining with the mitochondrial-specific fluorescent probe MitoSox suggested increased levels of superoxide in patient cells with reduced levels of sacsin. Key to maintaining mitochondrial health is mitochondrial fission, which facilitates the dynamic exchange of mitochondrial components and separates damaged parts of the mitochondrial network for selective elimination by mitophagy. Fission is dependent on dynamin-related protein 1 (Drp1), which is recruited to prospective sites of division where it mediates scission. In sacsin knockdown cells and ARSACS fibroblasts, we observed a decreased incidence of mitochondrial associated Drp1 foci. This phenotype persists even when fission is induced by drug treatment. Mitochondrial-associated Drp1 foci are also smaller in sacsin knockdown cells and ARSACS fibroblasts. These data suggest a model for ARSACS where neurons with reduced levels of sacsin are compromised in their ability to recruit or retain Drp1 at the mitochondrial membrane leading to a decline in mitochondrial health, potentially through impaired mitochondrial quality control.
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影响因子：
3.5
作者：
Parfitt DA;Michael GJ;Vermeulen EG;Prodromou NV;Webb TR;Gallo JM;Cheetham ME;Nicoll WS;Blatch GL;Chapple JP
通讯作者：
Chapple JP
影响因子：
3.5
作者：
Chen H;Chan DC
通讯作者：
Chan DC
DOI：
10.1016/s0925-4439(97)00070-7
发表时间：
1997-11-28
影响因子：
6.2
作者：
Cassarino, DS;Fall, CP;Bennett, JP
通讯作者：
Bennett, JP
影响因子：
3.9
作者：
Romano, Alessandro;Tessa, Alessandra;Barca, Amilcare;Fattori, Fabiana;de Leva, Maria Fulvia;Terracciano, Alessandra;Storelli, Carlo;Santorelli, Filippo Maria;Verri, Tiziano
通讯作者：
Verri, Tiziano
影响因子：
16.8
作者：
通讯作者：
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