Cortical Polarity of the RING Protein PAR-2 Is Maintained by Exchange Rate Kinetics at the Cortical-Cytoplasmic Boundary.
Cortical Polarity of the RING Protein PAR-2 Is Maintained by Exchange Rate Kinetics at the Cortical-Cytoplasmic Boundary.
复制标题
RING 蛋白 PAR-2 的皮质极性由皮质-细胞质边界的汇率动力学维持。
DOI：
10.1016/j.celrep.2016.09.044
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发表时间：
2016
期刊：
影响因子：
8.8
通讯作者：
Y. Sako
中科院分区：
文献类型：
--
作者：
Yukinobu Arata;M. Hiroshima;C. Pack;Ravikrishna Ramanujam;F. Motegi;K. Nakazato;Yuki Shindo;P. Wiseman;H. Sawa;Tetsuya J. Kobayashi;Hugo B. Brandão;T. Shibata;Y. Sako
细胞极性是通过极性调节剂的空间隔离产生的。 PAR 蛋白是极性调节剂，不对称地定位于两个相对的皮质域。然而，尚不清楚空间分离的 PAR 蛋白如何相互作用以维持其相互排斥的分配。在这里，对秀丽隐杆线虫胚胎的单分子检测分析表明，皮质 PAR-2 仅扩散短距离，因此，大多数 PAR-2 分子与皮质结合和解离，而不会进入相反的域。我们的结果表明，皮质 PAR-2 不对称性是由皮质-细胞质边界发生的局部交换反应维持的。此外，我们证明局部交换反应足以在无参数数学模型中维持皮质不对称性。这些发现表明前部和后部 PAR 蛋白主要通过细胞质库而不是通过皮质扩散相互作用。
Cell polarity arises through the spatial segregation of polarity regulators. PAR proteins are polarity regulators that localize asymmetrically to two opposing cortical domains. However, it is unclear how the spatially segregated PAR proteins interact to maintain their mutually exclusive partitioning. Here, single-molecule detection analysis inCaenorhabditis elegansembryos reveals that cortical PAR-2 diffuses only short distances, and, as a result, most PAR-2 molecules associate and dissociate from the cortex without crossing into the opposing domain. Our results show that cortical PAR-2 asymmetry is maintained by the local exchange reactions that occur at the cortical-cytoplasmic boundary. Additionally, we demonstrate that local exchange reactions are sufficient to maintain cortical asymmetry in a parameter-free mathematical model. These findings suggest that anterior and posterior PAR proteins primarily interact through the cytoplasmic pool and not via cortical diffusion.