CHCHD2 harboring Parkinson's disease-linked T61I mutation precipitates inside mitochondria and induces precipitation of wild-type CHCHD2
CHCHD2 harboring Parkinson's disease-linked T61I mutation precipitates inside mitochondria and induces precipitation of wild-type CHCHD2
复制标题
DOI：
10.1093/hmg/ddaa028
复制
发表时间：
2020-04-01
影响因子：
3.5
通讯作者：
Vandenberghe, Wim
中科院分区：
文献类型：
--
作者：
Cornelissen, Tom;Spinazzi, Marco;Vandenberghe, Wim
盘绕-盘绕-盘绕-盘绕-盘绕-盘绕-盘绕-盘绕-盘绕-盘绕-盘绕-盘绕结构域2 （CHCHD2）的T61I突变可导致常染色体显性形式的帕金森病（PD），但其潜在的致病机制尚不清楚。在这里，我们比较了野生型（WT）和T61I突变体CHCHD2在人细胞中的亚细胞定位和溶解度。我们发现WT和T61I CHCHD2的线粒体靶向依赖于c -末端coil- coil-helix-coil -coil-helix （CHCH）结构域的四个半胱氨酸残基，而不依赖于n -末端预测的线粒体靶向序列。T61I突变不会干扰突变蛋白的线粒体靶向，但会诱导其在IMS中沉淀。此外，T61I CHCHD2诱导线粒体活性氧产生增加和细胞凋亡，这可以通过抗氧化剂处理来阻止。通过CHCH结构域半胱氨酸残基的突变将T61I CHCHD2保留在细胞质中，阻止了其沉淀和诱导凋亡的作用。重要的是，T61I CHCHD2可能会削弱WT CHCHD2的溶解度。总之，我们的数据表明，T61I突变使突变体CHCHD2在线粒体内不溶，表明突变蛋白的功能丧失。此外，T61I CHCHD2对WT CHCHD2的溶解度产生显性负向影响，解释了这种PD形式的显性遗传。
The T61I mutation in coiled-coil-helix-coiled-coil-helix domain containing 2 (CHCHD2), a protein residing in the mitochondrial intermembrane space (IMS), causes an autosomal dominant form of Parkinson's disease (PD), but the underlying pathogenic mechanisms are not well understood. Here, we compared the subcellular localization and solubility of wild-type (WT) and T61I mutant CHCHD2 in human cells. We found that mitochondrial targeting of both WT and T61I CHCHD2 depended on the four cysteine residues in the C-terminal coiled-coil-helix-coiled-coil-helix (CHCH) domain but not on the N-terminal predicted mitochondrial targeting sequence. The T61I mutation did not interfere with mitochondrial targeting of the mutant protein but induced its precipitation in the IMS. Moreover, T61I CHCHD2 induced increased mitochondrial production of reactive oxygen species and apoptosis, which was prevented by treatment with anti-oxidants. Retention of T61I CHCHD2 in the cytosol through mutation of the cysteine residues in the CHCH domain prevented its precipitation as well as its apoptosis-inducing effect. Importantly, T61I CHCHD2 potently impaired the solubility of WT CHCHD2. In conclusion, our data show that the T61I mutation renders mutant CHCHD2 insoluble inside mitochondria, suggesting loss of function of the mutant protein. In addition, T61I CHCHD2 exerts a dominant-negative effect on the solubility of WT CHCHD2, explaining the dominant inheritance of this form of PD.