Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892.
J Cell Biol. 2013 Sep 30;202(7):1013-22. doi: 10.1083/jcb.201303141.
Centrosomes determine the mitotic axis of asymmetrically dividing stem cells. Several studies have shown that the centrosomes of the Drosophila melanogaster central brain neural stem cells are themselves asymmetric, organizing varying levels of pericentriolar material and microtubules. This asymmetry produces one active and one inactive centrosome during interphase. We identify pericentrin-like protein (PLP) as a negative regulator of centrosome maturation and activity. We show that PLP is enriched on the inactive interphase centrosome, where it blocks recruitment of the master regulator of centrosome maturation, Polo kinase. Furthermore, we find that ectopic Centrobin expression influenced PLP levels on the basal centrosome, suggesting it may normally function to regulate PLP. Finally, we conclude that, although asymmetric centrosome maturation is not required for asymmetric cell division, it is required for proper centrosome segregation to the two daughter cells.
中心体决定不对称分裂干细胞的有丝分裂轴。几项研究表明，果蝇中枢脑神经干细胞的中心体本身就是不对称的，组织不同水平的中心粒周围物质和微管。这种不对称性在间期产生一个活跃的和一个不活跃的中心体。我们确定中心体蛋白样蛋白 (PLP) 是中心体成熟和活性的负调节剂。我们表明，PLP 在不活跃的间期中心体上富集，在那里它阻止了中心体成熟的主调控因子 Polo 激酶的招募。此外，我们发现异位 Centrobin 表达影响基底中心体上 PLP 的水平，表明它可能正常发挥作用来调节 PLP。最后，我们得出结论，尽管不对称的中心体成熟不是不对称细胞分裂所必需的，但它是正确的中心体分离到两个子细胞所必需的。
