Gurdon Institute and Department of Physiology, Development and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
Dev Cell. 2013 Sep 30;26(6):604-15. doi: 10.1016/j.devcel.2013.08.014.
Controlling the position of the nucleus is vital for a number of cellular processes from yeast to humans. In Drosophila nurse cells, nuclear positioning is crucial during dumping, when nurse cells contract and expel their contents into the oocyte. We provide evidence that in nurse cells, continuous filopodia-like actin cables, growing from the plasma membrane and extending to the nucleus, achieve nuclear positioning. These actin cables move nuclei away from ring canals. When nurse cells contract, actin cables associate laterally with the nuclei, in some cases inducing nuclear turning so that actin cables become partially wound around the nuclei. Our data suggest that a perinuclear actin meshwork connects actin cables to nuclei via actin-crosslinking proteins such as the filamin Cheerio. We provide a revised model for how actin structures position nuclei in nurse cells, employing evolutionary conserved machinery.
控制细胞核的位置对于从酵母到人等多种细胞过程至关重要。在果蝇营养细胞中，细胞核定位在排出过程中至关重要，此时营养细胞收缩并将其内容物排入卵母细胞。我们提供的证据表明，在营养细胞中，从质膜延伸到细胞核的连续的、类似丝状伪足的肌动蛋白电缆，实现了细胞核的定位。这些肌动蛋白电缆将细胞核从环道上移开。当营养细胞收缩时，肌动蛋白电缆与细胞核侧向结合，在某些情况下诱导核旋转，使肌动蛋白电缆部分缠绕在细胞核周围。我们的数据表明，核周肌动蛋白网格通过肌动蛋白交联蛋白（如 Filamin Cheerio）将肌动蛋白电缆与细胞核连接起来。我们提供了一个经过修正的模型，说明肌动蛋白结构如何利用进化保守的机制在营养细胞中定位细胞核。
