A novel protein with RNA-binding motifs interacts with ataxin-2
A novel protein with RNA-binding motifs interacts with ataxin-2
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DOI：
10.1093/hmg/9.9.1303
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发表时间：
2000-05-22
影响因子：
3.5
通讯作者：
Pulst, SM
中科院分区：
文献类型：
--
作者：
Shibata, H;Huynh, DP;Pulst, SM
脊髓小脑性共济失调2型（SCA 2）是由共济失调蛋白-2（一种功能未知的蛋白质）中多聚谷氨酰胺束扩张引起的。利用酵母双杂交系统，我们鉴定了一个新的蛋白质，A2 BP 1（ataxin-2 binding protein 1），它与ataxin-2的C-末端结合。北方印迹分析表明A2 BP 1主要在肌肉和脑中表达。通过免疫荧光染色，A2 BP 1和ataxin-2均定位于trans-Golgi网络。免疫细胞化学显示，A2 BP 1在浦肯野细胞和齿状回神经元的细胞质中表达，其模式与ataxin-2标记相似。亚细胞组分的Western blot分析表明A2 BP 1在与ataxin-2相同的组分中富集。A2 BP 1 cDNA的序列分析显示在RNA结合蛋白中高度保守的RNP基序。A2 BP 1与功能未知的人cDNA克隆P83 A20具有惊人的同源性，并且在秀丽隐杆线虫基因组数据库中发现了至少两个拷贝的A2 BP 1同源物。A2 BP 1和相关蛋白似乎形成了一个新的基因家族，共享RNA结合基序。
Spinocerebellar ataxia type 2 (SCA2) is caused by expansion of a polyglutamine tract in ataxin-2, a protein of unknown function. Using the yeast two-hybrid system, we identified a novel protein, A2BP1 (ataxin-2 binding protein 1) which binds to the C-terminus of ataxin-2. Northern blot analysis showed that A2BP1 was predominantly expressed in muscle and brain. By immunocfluorescent staining, A2BP1 and ataxin-2 were both localized to the trans-Golgi network. Immunocytochemistry showed that A2BP1 was expressed in the cytoplasm of Purkinje cells and dentate neurons in a pattern similar to that seen for ataxin-2 labeling. Western blot analysis of subcellular fractions indicated enrichment of A2BP1 in the same fractions as ataxin-2, Sequence analysis of the A2BP1 cDNA revealed an RNP motif that is highly conserved among RNA-binding proteins. A2BP1 had striking homology with a human cDNA clone, P83A20, of unknown function and at least two copies of A2BP1 homologs are found in the Caenorhabditis elegans genome database. A2BP1 and related proteins appear to form a novel gene family sharing RNA-binding motifs.