School of Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
J Cell Biol. 2012 Aug 6;198(3):343-55. doi: 10.1083/jcb.201201087. Epub 2012 Jul 30.
Exchange between the nucleus and the cytoplasm is controlled by nuclear pore complexes (NPCs). In animals, NPCs are anchored by the nuclear lamina, which ensures their even distribution and proper organization of chromosomes. Fungi do not possess a lamina and how they arrange their chromosomes and NPCs is unknown. Here, we show that motor-driven motility of NPCs organizes the fungal nucleus. In Ustilago maydis, Aspergillus nidulans, and Saccharomyces cerevisiae fluorescently labeled NPCs showed ATP-dependent movements at ~1.0 µm/s. In S. cerevisiae and U. maydis, NPC motility prevented NPCs from clustering. In budding yeast, NPC motility required F-actin, whereas in U. maydis, microtubules, kinesin-1, and dynein drove pore movements. In the latter, pore clustering resulted in chromatin organization defects and led to a significant reduction in both import and export of GFP reporter proteins. This suggests that fungi constantly rearrange their NPCs and corresponding chromosomes to ensure efficient nuclear transport and thereby overcome the need for a structural lamina.
核质交换受核孔复合体（NPC）控制。在动物中，NPC 由核纤层锚定，这确保了 NPC 的均匀分布和染色体的适当组织。真菌没有核纤层，它们如何排列染色体和 NPC 尚不清楚。在这里，我们表明 NPC 的马达驱动运动组织了真菌核。在构巢曲霉、米曲霉和酿酒酵母中，荧光标记的 NPC 显示出依赖于 ATP 的运动，速度约为 1.0 µm/s。在酿酒酵母和构巢曲霉中，NPC 运动阻止了 NPC 的聚集。在芽殖酵母中，NPC 运动需要 F-肌动蛋白，而在构巢曲霉中，微管、驱动蛋白-1 和动力蛋白驱动孔运动。在后一种情况下，孔聚集导致染色质组织缺陷，并导致 GFP 报告蛋白的输入和输出显著减少。这表明真菌不断重新排列它们的 NPC 和相应的染色体，以确保有效的核运输，从而克服对结构纤层的需求。
