Functional analysis of actin-binding protein Tropomyosin4 in the spindle formation and orientation

哺乳动物卵母细胞高度极化是因为纺锤体向卵母细胞皮层的不对称迁移保证了在两次减数分裂中小极体的挤压。为了阐明维持这种极性的机制，我分析了肌动蛋白丝相关蛋白原肌球蛋白4（Tm4）的功能。siRNA缺失tm4导致卵母细胞纺锤体异常，纺锤体极性扩散。这些数据表明，在减数分裂过程中，Tm4在纺锤体取向和染色体迁移中起重要作用。

The mammalian oocyte is highly polarized because asymmetrical spindle migration to the oocyte cortex ensures extrusion of small polar bodies in the two meiotic divisions. To elucidate the mechanism of maintain this polarity, I analyzed the function of an actin-filament associated protein tropomyosin 4(Tm4). Tm4-depletion by siRNA causes abnormal spindles with diffused poles and polarity of spindles in oocyte. These data indicate that Tm4 plays important roles in spindle orientation and chromosome migration during meiosis.