Woodruff Jeffrey B, Wueseke Oliver, Viscardi Valeria, Mahamid Julia, Ochoa Stacy D, Bunkenborg Jakob, Widlund Per O, Pozniakovsky Andrei, Zanin Esther, Bahmanyar Shirin, Zinke Andrea, Hong Sun Hae, Decker Marcus, Baumeister Wolfgang, Andersen Jens S, Oegema Karen, Hyman Anthony A
Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany.
Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA.
Science. 2015 May 15;348(6236):808-12. doi: 10.1126/science.aaa3923.
The centrosome organizes microtubule arrays within animal cells and comprises two centrioles surrounded by an amorphous protein mass called the pericentriolar material (PCM). Despite the importance of centrosomes as microtubule-organizing centers, the mechanism and regulation of PCM assembly are not well understood. In Caenorhabditis elegans, PCM assembly requires the coiled-coil protein SPD-5. We found that recombinant SPD-5 could polymerize to form micrometer-sized porous networks in vitro. Network assembly was accelerated by two conserved regulators that control PCM assembly in vivo, Polo-like kinase-1 and SPD-2/Cep192. Only the assembled SPD-5 networks, and not unassembled SPD-5 protein, functioned as a scaffold for other PCM proteins. Thus, PCM size and binding capacity emerge from the regulated polymerization of one coiled-coil protein to form a porous network.
中心体在动物细胞内组织微管阵列，由两个中心粒组成，周围环绕着一种称为中心粒外周物质（PCM）的无定形蛋白质团块。尽管中心体作为微管组织中心很重要，但PCM组装的机制和调控仍未得到很好的理解。在秀丽隐杆线虫中，PCM组装需要卷曲螺旋蛋白SPD-5。我们发现重组SPD-5在体外可以聚合形成微米级的多孔网络。网络组装受到两种在体内控制PCM组装的保守调节因子——类Polo样激酶-1和SPD-2/Cep192的加速。只有组装好的SPD-5网络，而不是未组装的SPD-5蛋白，能作为其他PCM蛋白的支架。因此，PCM的大小和结合能力源于一种卷曲螺旋蛋白的调控聚合，以形成多孔网络。
