The RAG1 homeodomain recruits HMG1 and HMG2 to facilitate recombination signal sequence binding and to enhance the intrinsic DNA-bending activity of RAG1-RAG2.
The RAG1 homeodomain recruits HMG1 and HMG2 to facilitate recombination signal sequence binding and to enhance the intrinsic DNA-bending activity of RAG1-RAG2.
复制标题
RAG1 同源域招募 HMG1 和 HMG2 以促进重组信号序列结合并增强 RAG1-RAG2 的内在 DNA 弯曲活性。
DOI：
10.1128/mcb.19.10.6532
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发表时间：
1999
影响因子：
5.3
通讯作者：
Spanopoulou,E
中科院分区：
文献类型：
--
作者：
Aidinis,V;Bonaldi,T;Beltrame,M;Santagata,S;Bianchi,ME;Spanopoulou,E
V(D)J重组是由RAG1-RAG2 （RAG1/2）复合物与七聚体-非聚体重组信号序列（RSS）特异性结合而引发的。仅用RAG1/2加高迁移率组蛋白HMG1或HMG2就可以在体外重建V(D)J重组反应的几个步骤。我们发现RAG1同域结构域直接与HMG1和HMG2的HMG盒子相互作用（HMG1,2）。这种相互作用促进了RAG1/2与RSS的结合，主要是通过促进与非amer基序的高亲和力结合。通过循环排列分析，我们发现RAG1/2复合物使RSS DNA在七聚体和非聚体基序之间弯曲。HMG1,2显著增强了23RSS的结合和弯曲，但对于在12RSS上形成弯曲的DNA中间体不是必需的。转染细胞中HMG1,2浓度的短暂增加增加了体内最终V(D)J重组体的产生。
V(D)J recombination is initiated by the specific binding of the RAG1-RAG2 (RAG1/2) complex to the heptamer-nonamer recombination signal sequences (RSS). Several steps of the V(D)J recombination reaction can be reconstituted in vitro with only RAG1/2 plus the high-mobility-group protein HMG1 or HMG2. Here we show that the RAG1 homeodomain directly interacts with both HMG boxes of HMG1 and HMG2 (HMG1,2). This interaction facilitates the binding of RAG1/2 to the RSS, mainly by promoting high-affinity binding to the nonamer motif. Using circular-permutation assays, we found that the RAG1/2 complex bends the RSS DNA between the heptamer and nonamer motifs. HMG1,2 significantly enhance the binding and bending of the 23RSS but are not essential for the formation of a bent DNA intermediate on the 12RSS. A transient increase of HMG1,2 concentration in transfected cells increases the production of the final V(D)J recombinants in vivo.