Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA.
Science. 2010 Aug 20;329(5994):956-9. doi: 10.1126/science.1189072.
Nuclei move to specific locations to polarize migrating and differentiating cells. Many nuclear movements are microtubule-dependent. However, nuclear movement to reorient the centrosome in migrating fibroblasts occurs through an unknown actin-dependent mechanism. We found that linear arrays of outer (nesprin2G) and inner (SUN2) nuclear membrane proteins assembled on and moved with retrogradely moving dorsal actin cables during nuclear movement in polarizing fibroblasts. Inhibition of nesprin2G, SUN2, or actin prevented nuclear movement and centrosome reorientation. The coupling of actin cables to the nuclear membrane for nuclear movement via specific membrane proteins indicates that, like plasma membrane integrins, nuclear membrane proteins assemble into actin-dependent arrays for force transduction.
核体会移动到特定位置，以实现迁移和分化细胞的极化。许多核体运动依赖于微管。然而，在迁移成纤维细胞中重新定向中心体的核体运动是通过一种未知的肌动蛋白依赖性机制发生的。我们发现，在外（nesprin2G）和内（SUN2）核膜蛋白的线性阵列在核体迁移期间组装在逆行的背侧肌动蛋白电缆上，并与肌动蛋白电缆一起移动。抑制 nesprin2G、SUN2 或肌动蛋白会阻止核体运动和中心体重定向。肌动蛋白电缆与核膜的耦合，通过特定的膜蛋白实现核体运动，这表明与质膜整合素一样，核膜蛋白组装成肌动蛋白依赖性阵列，以进行力转导。
