RAG-1 INTERACTS WITH THE REPEATED AMINO-ACID MOTIF OF THE HUMAN HOMOLOG OF THE YEAST PROTEIN SRP1
RAG-1 INTERACTS WITH THE REPEATED AMINO-ACID MOTIF OF THE HUMAN HOMOLOG OF THE YEAST PROTEIN SRP1
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DOI：
10.1073/pnas.91.16.7633
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发表时间：
1994-08-02
影响因子：
11.1
通讯作者：
BALTIMORE, D
中科院分区：
文献类型：
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作者：
CORTES, P;YE, ZS;BALTIMORE, D
免疫球蛋白和T细胞受体的基因通过称为V（D）J重组的过程产生。该过程由重组激活蛋白RAG-1和RAG-2高度调节和介导。通过使用双杂交蛋白质相互作用系统，我们分离了一种与RAG-1特异性相互作用的人蛋白质。这种蛋白质是酵母SRP 1（温度敏感性RNA聚合酶I突变的抑制因子）的人类同源物。SRP 1 -1突变是酿酒酵母RNA聚合酶I 190 kDa亚基锌结合域温度敏感突变的等位基因特异性显性抑制因子。人SRP cDNA克隆用于筛选小鼠cDNA文库。我们获得了一个3.9 kbp的cDNA克隆编码的小鼠SRP 1。该cDNA的开放阅读框编码一个538个氨基酸的蛋白质，具有8个简并重复序列，每个重复序列40-45个氨基酸。小鼠和人类SRP 1有98%的相同性，而小鼠和酵母SRP 1有48%的相同性。将RAG-1和人SRP 1基因共转染293 T细胞后，明显形成了稳定的复合物。RAG-1与SRP 1蛋白相互作用的区域包括4个重复序列，RAG-1与SRP 1蛋白相互作用的区域位于锌指结构域的N端。因为RAG-1的这一区域不需要重组，而且SRP 1似乎与核膜结合，我们认为这种相互作用有助于RAG-1的定位。
Genes for immunoglobulins and T-cell receptor are generated by a profess known as V(D)J recombination. This process is highly regulated and mediated by the recombination activating proteins RAG-1 and RAG-2. By the use of the two-hybrid protein interaction system, we isolated a human protein that specifically interacts with RAG-1. This protein is the human homologue of the yeast SRP1 (suppressor of a temperature-sensitive RNA polymerase I mutation). The SRP1-1 mutation is an allele-specific dominant suppressor of a temperature-sensitive mutation in the zinc binding domain of the 190-kDa subunit of Saccharomyces cerevisiae RNA polymerase I. The human SRP cDNA clone was used to screen a mouse cDNA library. We obtained a 3.9-kbp cDNA clone encoding the mouse SRP1. The open reading frame of this cDNA encodes a 538-amino acid protein with eight degenerate repeats of 40-45 amino acids each. The mouse and human SRP1 are 98% identical, while the mouse and yeast SRP1 have 48% identity. After cotransfection of the genes encoding RAG-1 and human SRP1 into 293T cells, a stable complex was evident. Deletion analysis indicated that the region of the SRP1 protein interacting with RAG-1 involved four repeats, The domain of RAG-1 that associates with SRP1 mapped N-terminal to the zinc finger domain. Because this region of RAG-1 is not required for recombination and SRP1 appears to be bound to the nuclear envelope, we suggest that this interaction helps to localize RAG-1.