Fried H, Kutay U
Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, USA, North Carolina 27599, USA.
Cell Mol Life Sci. 2003 Aug;60(8):1659-88. doi: 10.1007/s00018-003-3070-3.
In eukaryotic cells, the enclosure of the genetic information in the nucleus allows the spatial and temporal separation of DNA replication and transcription from cytoplasmic protein synthesis. This compartmentalization not only permits a high level of regulation of these processes but at the same time necessitates a system of selective macromolecular transport between the nucleus and the cytoplasm. Transfer of macromolecules between both compartments is mediated by soluble receptors that interact with components of nuclear pore complexes (NPCs) to move their specific cargos. Transport occurs by way of a great variety of different pathways defined by individual receptors and accessory factors. Often, processes in substrate biogenesis that precede transport concurrently recruit transport factors to substrates, thus making transport responsive to correct and orderly synthesis of substrates. Some current challenges are to understand how transport factor-substrate interactions are controlled and integrated with sequential steps in substrate biogenesis, how large macromolecular complexes are restructured to fit through the NPC channel and to understand how transport factor-NPC interactions lead to actual translocation through the NPC.
在真核细胞中，遗传信息被包裹在细胞核内，使得DNA复制和转录与细胞质中的蛋白质合成在空间和时间上得以分离。这种区室化不仅允许对这些过程进行高度调控，同时也需要一个在细胞核和细胞质之间进行选择性大分子运输的系统。大分子在两个区室之间的转移由可溶性受体介导，这些受体与核孔复合体（NPC）的成分相互作用，以运输其特定的货物。运输通过由个体受体和辅助因子定义的多种不同途径进行。通常，在运输之前的底物生物合成过程会同时将运输因子招募到底物上，从而使运输对底物的正确和有序合成做出响应。当前的一些挑战包括了解运输因子与底物的相互作用是如何被控制的，以及如何与底物生物合成中的连续步骤整合在一起；了解大分子复合物如何重新构建以通过NPC通道；以及了解运输因子与NPC的相互作用如何导致通过NPC的实际转运。
