Functional histone antibody fragments traverse the nuclear envelope
Functional histone antibody fragments traverse the nuclear envelope
复制标题
功能性组蛋白抗体片段穿过核膜
作者：
L. Einck;M. Bustin
通过显微注射荧光标记的非免疫IgG和F（ab）2或相应的分子，从组蛋白的抗血清中制备的，到人成纤维细胞的细胞核和细胞质中的蛋白质的易位过程中的重要因素进行了研究。来自两种制剂的完整IgG保留在注射部位，无论其是注射到细胞核还是细胞质中。与此相反，非免疫F（ab）2均匀分布在整个细胞。来自亲和纯抗组蛋白的F（ab）2在胞质注射后进入细胞核，并在核显微注射后保留在细胞核中。抗组蛋白F（ab）2迁移到细胞核中导致尿苷掺入到显微注射细胞的细胞核中的抑制。我们的结论是，非核蛋白，缺乏特定的信号序列，穿越核膜和积累在细胞核中提供其回转半径小于55 A和细胞核含有这些分子的结合位点。这些发现支持了“准双功能结合位点”作为蛋白质核积累驱动力的模型。结果还表明，活性F（ab）2片段，显微注射到体细胞中，可以结合到它们的抗原位点，这表明活性抗体片段的显微注射可用于研究活细胞中的核组分的位置和功能。
Factors important in the translocation process of proteins across the nuclear membrane were studied by microinjecting either fluoresceinated nonimmune IgG and F(ab)2 or the corresponding molecules, prepared from antisera to histones, into the nucleus and cytoplasm of human fibroblasts. Intact IgG from both preparations remained at the site of injection regardless of whether it was injected into the nucleus or the cytoplasm. In contrast, nonimmune F(ab)2 distributed uniformly throughout the cell. The F(ab)2 derived from affinity-pure antihistone moves into the nucleus after cytoplasmic injection and remains in the nucleus after nuclear microinjection. The migration of the antihistone F(ab)2 into the nucleus results in inhibition of uridine incorporation in the nuclei of the microinjected cells. We conclude that non-nuclear proteins, devoid of specific signal sequences, traverse the nuclear membrane and accumulate in the nucleus provided their radius of gyration is less than 55A and the nucleus contains binding sites for these molecules. These findings support the model of "quasibifunctional binding sites" as a driving force for nuclear accumulation of proteins. The results also indicate that active F(ab)2 fragments, microinjected into somatic cells, can bind to their antigenic sites suggesting that microinjection of active antibody fragments can be used to study the location and function of nuclear components in living cells.
多头绒泡菌细胞核和细胞质之间与细胞周期相关的蛋白质转移。
影响因子：
3.7
作者：
JeterJr,JR;Cameron,IL;Hart,NE;Rusch,HP
通讯作者：
Rusch,HP