Saitoh H, Dasso M
Laboratory of Molecular Embryology, NICHD, National Institutes of Health, Bethesda, Maryland 20892-5430, USA.
J Biol Chem. 1995 May 5;270(18):10658-63. doi: 10.1074/jbc.270.18.10658.
RCC1 is an abundant, highly conserved, chromatin-associated protein whose function is necessary for the preservation of a properly ordered cell cycle. RCC1 is also necessary for numerous nuclear processes, including nuclear transport and RNA metabolism; and it functions enzymatically as a guanine nucleotide exchange factor for a small, ras-related GTPase called Ran. Studies in several organisms suggest that RCC1 may be part of a large complex containing multiple proteins. There is also evidence that RCC1 associates with chromatin through other proteins and that the binding of the complex to chromatin varies within the cell cycle. In order to characterize this putative complex, we have identified a number of other proteins as candidate components of the complex by their association with a GST-RCC1 fusion protein. Three of these proteins have previously been identified (Ran, RanBP1, and hsc70). The fourth protein is novel and has a molecular mass of 340 kDa. In this report, we discuss a preliminary characterization of the interactions between these proteins.
RCC1是一种含量丰富、高度保守且与染色质相关的蛋白质，其功能对于维持正常有序的细胞周期是必需的。RCC1对于众多核过程也是必需的，包括核转运和RNA代谢；并且它作为一种鸟嘌呤核苷酸交换因子，对一种名为Ran的小的、与ras相关的GTP酶发挥酶促作用。对多种生物体的研究表明，RCC1可能是包含多种蛋白质的大型复合物的一部分。也有证据表明，RCC1通过其他蛋白质与染色质结合，并且该复合物与染色质的结合在细胞周期内有所不同。为了表征这种假定的复合物，我们通过与GST-RCC1融合蛋白的结合，鉴定了许多其他蛋白质作为该复合物的候选成分。其中三种蛋白质先前已被鉴定（Ran、RanBP1和hsc70）。第四种蛋白质是新发现的，分子量为340 kDa。在本报告中，我们讨论了这些蛋白质之间相互作用的初步表征。
