Aguilera R J, Akira S, Okazaki K, Sakano H
Department of Microbiology and Immunology, University of California, Berkeley 94720.
Cell. 1987 Dec 24;51(6):909-17. doi: 10.1016/0092-8674(87)90578-2.
DNA-nuclear protein interactions were studied with synthetic recombination signal sequences (RSSs) for immunoglobulin V-J joining. With a gel retardation assay, a DNA-binding protein that specifically interacts with RSSs was detected in nuclear extracts from a pre-B cell line, 38B9. This protein was found in all the recombination-competent pre-B cell lines tested in this study, but not in myeloma, mature T cell, monocyte, or fibroblast cell lines. DNA footprint analysis with dimethyl sulfate demonstrated that the 7-mer region of the RSS was strongly protected when complexed with the binding protein. Furthermore, a single base substitution in the 7-mer region totally abolished the binding. The molecular mechanism of V-J joining is discussed in the context of the RSS-binding protein.
利用用于免疫球蛋白V-J连接的合成重组信号序列(RSSs)研究了DNA与核蛋白的相互作用。通过凝胶阻滞试验,在一个前B细胞系38B9的核提取物中检测到一种与RSSs特异性相互作用的DNA结合蛋白。在本研究中测试的所有具有重组能力的前B细胞系中都发现了这种蛋白,但在骨髓瘤、成熟T细胞、单核细胞或成纤维细胞系中未发现。用硫酸二甲酯进行的DNA足迹分析表明,当与结合蛋白复合时,RSS的7聚体区域受到强烈保护。此外,7聚体区域中的单个碱基取代完全消除了结合。在RSS结合蛋白的背景下讨论了V-J连接的分子机制。