Deletion of exons encoding carboxypeptidase domain of Nna1 results in Purkinje cell degeneration (pcd) phenotype
Deletion of exons encoding carboxypeptidase domain of Nna1 results in Purkinje cell degeneration (pcd) phenotype
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编码 Nna1 羧肽酶结构域的外显子缺失导致浦肯野细胞变性 (pcd) 表型
DOI：
10.1111/jnc.14591
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发表时间：
2018
影响因子：
4.7
通讯作者：
Takebayashi Hirohide
中科院分区：
文献类型：
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作者：
Zhou Li;Hossain M. Ibrahim;Yamazaki Maya;Abe Manabu;Natsume Rie;Konno Kohtaro;Kageyama Shun;Komatsu Masaaki;Watanabe Masahiko;Sakimura Kenji;Takebayashi Hirohide
浦肯野细胞变性（pcd）首先在一个自发性突变的小鼠小脑共济失调中发现。除了小脑浦肯野细胞（PC），视网膜光感受器，嗅球中的僧帽细胞和丘脑神经元的离散亚群也在突变体大脑中退化。导致pcd突变的基因是Nna 1，也称为ATP/GTP结合蛋白1或胞质羧肽酶样1，它编码锌羧肽酶蛋白。为了详细研究pcd突变的发病机制，我们产生了一个条件性Nna 1等位基因，靶向C末端的羧肽酶结构域。通过Cre重组和杂合子杂交，我们获得了Nna 1基因敲除（KO）小鼠，发现Nna 1基因敲除小鼠在出生后20天（P20）开始出现小脑共济失调。大多数PC退化至4周龄，X小叶除外。在Nna 1 KO小脑中也观察到活化的小胶质细胞和星形胶质细胞。由于Nna 1蛋白在α微管蛋白和β微管蛋白的C末端起脱谷氨酸酶的作用，因此在Nna 1 KO小脑中检测到增加的多聚谷氨酰化微管蛋白。此外，内质网应激标志物C/EBP同源蛋白（CHOP）在突变PC中上调。我们报告了一个功能性Nna 1条件等位基因的产生和小脑中Nna 1 KO中PC死亡的可能机制。开放实践这篇文章获得了 * 开放材料 * 的徽章，因为它提供了所有相关信息来重现手稿中的研究。本文的完整开放科学披露表格可以在文章末尾找到。有关开放实践徽章的更多信息，请访问https://cos.io/our-services/open-science-badges/。
Purkinje cell degeneration (pcd) was first identified in a spontaneous mouse mutant showing cerebellar ataxia. In addition to cerebellar Purkinje cells (PCs), retinal photoreceptors, mitral cells in the olfactory bulb, and a discrete subpopulation of thalamic neurons also degenerate in the mutant brains. The gene responsible for thepcdmutant isNna1, also known asATP/GTP binding protein 1orcytosolic carboxypeptidase‐like 1,which encodes a zinc carboxypeptidase protein. To investigate pathogenesis of thepcdmutation in detail, we generated a conditionalNna1allele targeting the carboxypeptidase domain at C‐terminus. After Cre recombination and heterozygous crossing, we generatedNna1knockout (KO) mice and found that theNna1KO mice began to show cerebellar ataxia at postnatal day 20 (P20). Most PCs degenerated until 4‐week‐old, except lobule X. Activated microglia and astrocytes were also observed in theNna1KO cerebellum. In the mutant brain, theNna1mRNA level was dramatically reduced, suggesting that nonsense‐mediated mRNA decay occurs in it. Since the Nna1 protein acts as a de‐glutamatase on the C‐terminus of α‐tubulin and β‐tubulin, increased polyglutamylated tubulin was detected in theNna1KO cerebellum. In addition, the endoplasmic reticulum stress marker, C/EBP homologous protein (CHOP), was up‐regulated in the mutant PCs. We report the generation of a functionalNna1conditional allele and possible mechanisms of PC death in theNna1KO in the cerebellum.Open PracticesThis article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.