Novel RING finger proteins, Air1p and Air2p, interact with Hmt1p and inhibit the arginine methylation of Npl3p
Novel RING finger proteins, Air1p and Air2p, interact with Hmt1p and inhibit the arginine methylation of Npl3p
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DOI：
10.1074/jbc.m004560200
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发表时间：
2000-10-20
影响因子：
4.8
通讯作者：
Hagiwara, M
中科院分区：
文献类型：
--
作者：
Inoue, K;Mizuno, T;Hagiwara, M
异质性核糖核蛋白(HnRNPs)参与mRNA的加工和输出，并通过其富含精氨酸-甘氨酸(RGG)结构域上的精氨酸残基甲基化而被翻译后修饰。我们在酿酒酵母中用双杂交系统筛选了只有在Hmt1p存在的情况下才能与Np13p的RGG结构域相互作用的因子。分离的克隆YIL079编码一种新的环指蛋白，该蛋白不直接与Np13p结合，但与Hmt1p的N端相关。因此，我们将基因产物命名为Air1p(精氨酸甲基转移酶相互作用环指蛋白)。Air1p体外抑制Hmt1p介导的Np13p甲基化。过表达的Air1p抑制了Hmt1p依赖的细胞生长。由于同源性搜索表明YDL175基因产物与Air1p有显著的同源性(45%)，因此我们将该基因命名为AIR2。Air2p也有一个无名指域名，并与Hmt1p绑定。虽然单独阻断这两个基因对细胞的生长没有影响，但缺少Air1p和Air2p的细胞生长速度极慢，细胞核中积累了Poly(A)(+)RNA。因此，Air1p和Air2p可能通过调节异质性核糖核蛋白的精氨酸甲基化状态来影响mRNA的转运。
Heterogeneous nuclear ribonucleoproteins (hnRNPs) are involved in the mRNA processing and export and are post-translationally modified by methylation at arginine residues in their arginine-glycine-rich (RGG) domains. We screened the factors that can interact with the RGG domain of Np13p only in the presence of Hmt1p with the two-hybrid system in Saccharomyces cerevisiae, An isolated clone, YIL079, encodes a novel RING finger protein that was not directly bound to Np13p but associated with the N terminus of Hmt1p. Thus, we designated the gene product Air1p (arginine methyltransferase-interacting RING finger protein). Air1p inhibited the Hmt1p-mediated methylation of Np13p in vitro. Overexpression of Air1p repressed the Hmt1p-dependent growth of cells. Since homology searches indicate that the YDL175 gene product has significant identity (45%) with Air1p, we designated the gene AIR2. Air2p also has a RING finger domain and was bound to Hmt1p. Although single disruption of either gene gave no effect on the cell growth, cells lacking Air1p and Air2p grew at an extremely slow rate with accumulated poly(A)(+) RNA in the nucleus. Thus, Air1p and Air2p may affect mRNA transport by regulating the arginine methylation state of heterogeneous nuclear ribonucleoproteins.